TO VIEW PROPERLY YOU MAY NEED TO SET YOUR BROWSER'S CHARACTER ENCODING TO UNICODE 8 OR 16 AND USE YOUR BACK BUTTON TO RE-LOAD CRUISE REPORT P01, P14 (UPDATED NOV 2014) HIGHLIGHTS CRUISE SUMMARY INFORMATION Section designation P01 P14 Leg 1 P14 Leg 2 Expedition designation 49NZ20070724 49NZ20071008 49NZ20071122 Chief Scientists Takeshi Kawano/ Takeshi Kawano/ Akihiko Murata/ JAMSTEC JAMSTEC JAMSTEC Dates 24 JUL 2007 - 08 OCT 2007 - 22 NOV 2007 - 20 NOV 2009 20 NOV 2007 26 DEC 2007 Ship R/V MIRAI Ports of call Hachinohe, Japan - Hachinohe, Japan - Dutch Harbor, U.S.A. Majuro, Marshall Islands - Auckland, New Zealand 47°01.87'N 59°00.11'N Geographic boundaries 145°27.26'E 124°58.91'W 175°2.04'E 173°59.8'W 39°41.32'N 35°38.06'S Stations 88 272 Floats and drifters 5 floats deployed 14 floats deployed Moorings 0 0 Recent Contact Information Takeshi Kawano • kawnaot@jamstec.go.jp / Akihiko Murata • akihiko.murata@jamstec.go.jp Ocean General Circulation Observational Research Program Institute of Observational Research for Global Change Japan Agency for Marine-earth Science and Technology 2-15, Natsushima, Yokosuka, Japan 237-0061 • Fax: +81-46-867-9455 WHP P01, P14 REVISIT DATA BOOK Edited by Takeshi Kawano (JAMSTEC) Hiroshi Uchida (JAMSTEC) Toshimasa Doi (JAMSTEC) WHP P01, P14 REVISIT - THE NORTHERN CROSS EXPEDITION OF MIRAI - Towards Intl. Repeat Hydrography and Carbon Program WHP P01, P14 REVISIT DATA BOOK March,1, 2009 Published Edited by Takeshi Kawano (JAMSTEC), Hiroshi Uchida (JAMSTEC) and Toshimasa Doi (JAMSTEC) Published by (c) JAMSTEC, Yokosuka, Kanagawa, 2009 Japan Agency for Marine-Earth Science and Technology 2-15 Natsushima, Yokosuka, Kanagawa. 237-0061, Japan Phone +81-46-867-9471, Fax +81-46-867-9455 Printed by Ryoin Co., Ltd. 12, Nishikichou, Naka-ward, Yokohama, 231-8715, Japan CONTENTS Preface M. Fukasawa (JAMSTEC) Documents and .sum files 1.Cruise Narrative T. Kawano (JAMSTEC) 2.Underway Measurements 2.1 Navigation and Bathymetry T. Matsumoto (Univ. Ryukyus) et al. 2.2 Surface Meteorological Observation K. Yoneyama (JAMSTEC) et al. 2.3 Thermosalinograph and related measurements Y. Kumamoto (JAMSTEC) et l. 2.4 Underway pCO2 A. Murata (JAMSTEC) et al. 2.5 Acoustic Doppler Current Profiler S. Kouketsu (JAMSTEC) et al. 2.6 XCTD H. Uchida (JAMSTEC) et al 3. Hydrographic Measurement Techniques and Calibrations 3.1 CTD/O2 Measurements H. Uchida (JAMSTEC) et al. 3.2 Salinity T. Kawano (JAMSTEC) et al. 3.3Oxygen Y. Kumamoto (JAMSTEC) et al. 3.4 Nutrients M. Aoyama (MRI/JMA) et.al. 3.5 Dissolved inorganic carbon (CT) A. Murata (JAMSTEC) et al. 3.6 Total Alkalinity A. Murata (JAMSTEC)et al. 3.7 pH A. Murata (JAMSTEC)et al. 3.8 CFCs K. Sasaki(JAMSTEC) et al. 3.9 Lowered Acoustic Doppler Current Profiler S. Kouketsu (JAMSTEC) et al. Station Summary 49MR0704_1.sum file. 49MR0706_1.sum file. 49MR0706_2.sum file. Figures Figure captions Station locations Bathymetry Surface wind Sea surface temperature Sea surface salinity ∆pCO2 Surface current Cross-sections Potential temperature Salinity Salinity (with SSW correction) Density (σ0) Density (σ4) Neutral density (γn) Oxygen Silicate Nitrate Nitrite Phosphate Dissolved inorganic carbon Total alkalinity pH CFC-11 CFC-12 CFC-12 Velocity Difference between WOCE and the revisit Potential temperature Salinity (with SSW correction) Oxygen .sum, .sea, .wct and other data files CD-ROM on the back cover PREFACE We, Ocean General Circulation Observational Research Program of IORGC (Institute of Observational Research for Global Change), published four data books after WHP (World Ocean Circulation Experiment Hydrographic Program) revisits along P17N, P6, A10, I3/I4, P3, P10, so far. It is our great pleasure that quite a few scientists in the world accepted our activities not only as references for their scientific works but also even as text books for education. In 2007, we carried out two cruises on R/V Mirai of JAMSTEC (Japan Agency for Marine Earth Science and Technology) as "The Northen Cross Expedition of Mira " in order to complete our interim research plan for the period from 2004 through 2008. Target of the cruises was to re-occupy WHP-P1 and WHP-P14 lines. WHP-P1 is the line occupied in 1985 by United States (Chief Scientist was Dr. Talley) and is the first WHP line that the quality of provided data almost the WOCE standard from the re-occupation by Japan in 1999. Through the re- occupation of WHP-P1, the warming of bottom waters in the North Pacific Sub- arctic was detected and a new view point of changes in the meridonal overturn was introduced. This re-occupation of WHP-P1 succeeded in demonstrating the fact that a re-occupation of a WHP line with as high data quality as WOCE standard was so powerful to promote studies on climatic changes in the ocean especially in the deeper layer. The third time re-occupation of WHP-P1, which is highlighted in this book, has objectives not only for confirming the bottom water warming. It is to detect Bio-Geochemical changes in the North Pacific Sub-arctic gyre because as far as carbon items concern, this cruise can be regarded as the second time re- occupation. Bio-Geochemical time series stations of K1(Japan) and P(Canada) are located in the western and the eastern ends of WHP-P1, respectively. Of these stations, K1 was established after the second time re-occupation of WHP-P1. Amount of new knowledge are expected to be brought through a comprehensive analysis of data from the WHP re-occupation and from time series stations. WHP-P14 is the line along the meridian of 175°E. This line was occupied during 1992 though 1996 by three cruises of P14C, P14N and P14S (Chief Scientists were Drs. Roden, Roemmich and Bullister, respectively). This line was selected to be re-occupied as the last long hydrographic ocean observation of the interim research plan of Ocean General Circulation Observational Research Program of IORGC because of two main reasons. The first one is to prepare new data sets of carbon items and of Freons in the center of the Pacific together with other data sets to bound the eastern extension of the bottom water warming. The second one is on rather long history. Japan Meteorological Agency has been declared to re-occupy WHP-P13 along 165°E since 2002 with the same data quality as of WOCE standard. The re-occupation of WHP-P13 was expected but it did not come true yet. On the other hand, the needs for hydrographic high quality data sets have become larger for the ocean climate research in the center of the Pacific. So, we decided to re-occupy WHP-P14, which is located close to WHP- P13, without interrupting the plan of Japan Meteorological Agency, though possible re-occupation of any zonal WHP line was more appropriate for us to estimate the meridonal heat, sea water and material transports. Finally, we would like to express our gratitude to all participants and crews of the R/V Mirai of the Japan Agency for Marine-earth Science and Technology, for their assistance in carrying out these cruises. The research system of JAMSTEC will be reformed largely in the fiscal year of 2009, however, we would like to continue our effort to re-occupy WHP lines with a vision of realizing a reliable prediction of global climate change. Data from those observations will be disseminated through our data book and web-sites of IORGC (http://www.jamstec.go.jp/iorgc/ocorp/data/post-wace.html), JAMSTEC (http://www.jamstec.go.jp/mirai/index_eng.html), IRHCP(International Repeat Hydrography and Carbon Project; http://cchdo.ucsd.edu/index.html), and CDIAC (Carbon Dioxide Information Analysis Center; http://cdiac.ornl.gov/oceans/RpeatSections/repeat_map.html). No permission is required to reproduce our data books and CDs. We only would like to ask a favor of all scientists to refer our data book of repeat hydrography as often as possible because such references prove that our efforts help the science not only of ourselves but also of all oceanographers and can make our activities for repeat hydrography sustainable. On International Day of Disabled Parsons at Yokosuka Masao Fukasawa Director-General, IORGC/JAMSTEC Program Director, Ocean General Circulation Observational Research Program of IORGC/JAMSTEC 1 CRUISE NARRATIVE 1.1 Highlight Cruise Code: MR07-04 and MR07-06 GHPO Section designation: P01 and P14 Chief Scientist: Takeshi Kawano (MR07-04 and MR07-06 Leg.1) kawnaot@jamstec.go.jp Akihiko Murata (MR07-06 Leg,2) akihiko.murata@jamstec.go.jp Ocean General Circulation Observational Research Program Institute of Observational Research for Global Change Japan Agency for Marine-earth Science and Technology 2-15, Natsushima, Yokosuka, Japan 237-0061 Fax: +81-46-867-9455 Ship: R/V MIRAI Ports of Call: MR07-04 Sekinehama - Hachinohe - Dutch Harbor MR07-06 Leg.1 Sekinehama - Hachinohe - Majuro MR07-06 Leg.2 Majuro - Auckland Cruise Date: MR07-04 July 24, 2007 - September 3, 2007 MR07-06 Leg.1 October 8, 2007 - November 20, 2007 MR07-06 Leg.2 November 22, 2007 - December 26, 2007 Number of Stations: MR07-04 88 stations MR07-06 Leg.1 143 stations MR07-06 Leg.2 129 stations Geographic boundaries: MR07-04 145°27.26'E - 124°58.91'W 47°01.87'N - 39°41.32'N MR07-06 152°05.43'E - 173°59.67'W 59°00.11'N - 35°38.06'S Floats and drifters deployed: MR07-04 5 floats MR07-06 14 floats Mooring deployed or recovered mooring: NONE 1.2 Cruise Summary (1) Station occupied MR07-04 A total of 88 stations was occupied using a Sea Bird Electronics 36 position carousel equipped with 12 liter Niskin X water sample bottles, a SBE911plus equipped with SBE35 deep ocean standards thermometer, SBE43 oxygen sensor, AANDERAA "optode" oxgen sensor and Benthos Inc. Altimeter and RDI Monitor ADCP. XCTDs were deployed at 18 stations. Cruise track and station location are shown in Figure 1.2.1(a). Fig.1.2.1(a): Cruise Track and hydrographic stations. Solid circle (•)and Triangle (∆) represents CTD station and XCTD station, respectively. Open circle (o) shows a position where ARGO floats were deployed. MR07-06 A total of 272 stations (143 for Leg.1 and 129 for Leg.2) was occupied using a Sea Bird Electronics 36 position carousel equipped with 12 liter Niskin X water sample bottles, a SBE911plus equipped with SBE35 deep ocean standards thermometer, SBE43 oxygen sensor, AANDERAA "optode" oxgen sensor and Benthos Inc. Altimeter and RDI Monitor ADCP. Cruise track and station location are shown in Figure 1.2.1(b). (2) Sampling and measurements Water samples were analyzed for salinity, oxygen, nutrients, CFC-11, -12, -113, total alkalinity, DIC, and pH. The sampling layers are coordinated as so-called staggered mesh. Samples for POM, 14C, 13C, 137Cs, N2O, CH4 and DMS in MR07-04 and samples for POC, 14C, 13C, 137Cs, Pu, Noble gases, stable isotopes of O2 and a biological study in MR07-06 were also collected at the selected stations. The bottle depth diagram is shown in Figure 1.2.2. Underway measurements of pCO2, temperature, salinity, oxygen, surface current, bathymetry and meteorological parameters were conducted along the cruise track. Fig. 1.2.1(b): Cruise Track and hydrographic stations. Solid circle (•) represents CTD station. Open circle (o) shows a position where ARGO floats were deployed. Fig. 1.2.2: The bottle depth diagram for (a) WHP-P1 and (b) WHP-P14. Brue cross (+) represents points where seawater was sampled in MR07-04 and red cross (+) represent points in MR07-06. (4) Floats and Drifters deployed ARGO floats were launched along the cruise track. The launched positions of the ARGO floats are listed in Table 1.2.1(a) and (b) for MR07-04 and MR07-06, respectively. Table 1.2.1(a): Launched positions of the ARGO float in MR07-04. ______________________________________________________________________________________ Float ARGOS Date and Time Date and Time S/N PTT ID of Reset (UTC) of Launch (UTC) Location of Launch St. No. ----- ------ ---------------- ---------------- ------------------------ ------- 2811 66102 2007/8/16 23:53 2007/8/17 00:58 46-59.46[N] 172-41.04[W] P01-068 2804 66095 2007/8/18 09:48 2007/8/18 12:12 46-59.34[N] 167-04.38[W] P01-073 2352 60118 2007/8/22 23:55 2007/8/23 01:32 46-59.69[N] 151-24.37[W] P01-087 3050 70495 2007/8/24 01:49 2007/8/24 03:51 46-59.35[N] 146-55.35[W] P01-091 3049 70494 2007/8/24 08:13 2007/8/24 10:17 46-58.81[N] 145-47.72[W] P01-092 ______________________________________________________________________________________ Table 1.2.1(b): Launched positions of the ARGO float in MR07-06 _______________________________________________________________________________________ Float ARGOS Date and Time Date and Time S/N PTT ID of Reset (UTC) of Launch (UTC) Location of Launch St. No. ----- ------ ---------------- ---------------- ------------------------ -------- 3268 33318 2007/10/24 03:18 2007/10/24 04:34 52-16.13[N] 178-58.20[W] P14N-015 3264 33314 2007/10/24 17:44 2007/10/24 18:55 53-29.83[N] 178-14.01[W] P14N-012 3265 33315 2007/10/25 08:44 2007/10/25 10:18 54-59.59[N] 177-09.45[W] P14N-009 3260 33306 2007/10/26 00:41 2007/10/26 01:55 56-29.22[N] 176-05.71[W] P14N-006 3261 33307 2007/10/27 06:31 2007/10/27 08:01 57-59.70[N] 174-53.87[W] P14N-003 3331 75743 2007/11/04 07:05 2007/11/04 08:33 36-58.62[N] 179-01.88[E] P14N-051 3330 75742 2007/11/05 04:13 2007/11/05 05:56 34-59.89[N] 178-59.80[E] P14N-055 3329 75741 2007/11/07 21:25 2007/11/07 23:52 28-58.83[N] 179-01.25[E] P14N-067 3328 75740 2007/11/08 21:30 2007/11/09 00:21 26-59.79[N] 179-01.77[E] P14N-071 3341 75753 2007/11/11 04:43 2007/11/11 05:54 25-00.27[N] 179-01.59[E] P14N-075 3333 75745 2007/11/13 01:18 2007/11/13 02:28 21-00.66[N] 178-59.88[E] P14N-083 3332 75744 2007/11/14 18:44 2007/11/14 21:36 17-01.42[N] 178-59.25[E] P14N-091 3343 75755 2007/11/16 21:04 2007/11/16 21:59 13-00.39[N] 178-59.33[E] P14N-099 3327 75739 2007/11/24 08:22 2007/11/24 10:05 08-00.17[N] 179-01.21[E] P14N-111 _______________________________________________________________________________________ (5) MOORINGS DEPLOYED OR RECOVERED No mooring was deployed nor recovered during the cruise. 1.3 LIST OF PRINCIPAL INVESTIGATORS AND PERSON IN CHARGE ON THE SHIP The principal investigator (PI) and the person in charge responsible for major parameters measured on the cruise are listed in Table 1.3.1. Table 1.3.1(a): List of principal investigators and persons in charge on the ship for MR07-04 ______________________________________________________________________________________ Item Principal Investigator Person in Charge on the Ship ------------- ------------------------------ ------------------------------------- Underway ADCP Shinya Kouketsu (JAMSTEC) Satoshi Okumura (GODI) skouketsu@jamstec.go.jp Bathymetry Takeshi Matsumoto (U. Ryukyus) Satoshi Okumura (GODI) tak@sci.u-ryukyu.ac.jp Meteorology Kunio Yoneyama (JAMSTEC) Satoshi Okumura (GODI) yoneyamak@jamstec.go.jp T-S Yuichiro Kumamoto (JAMSTEC) Keisuke Wataki (MWJ) kumamoto@jamstec.go.jp pCO2 Akihiko Murata (JAMSTEC) Yoshiko Ishikawa, Yasuhiro Arii (MWJ) akihiko.murata@jamstec.go.jp Hydrography CTD/O2 Hiroshi Uchida (JAMSTEC) Satoshi Ozawa (MWJ) huchida@jamstec.go.jp LADCP Shinya Kouketsu (JAMSTEC) Shinya Kouketsu (JAMSTEC) skouketsu@jamstec.go.jp Salinity Takeshi Kawano (JAMSTEC) Naoko Takahashi (MWJ) kawanot@jamstec.go.jp Oxygen Yuichiro Kumamoto (JAMSTEC) Kimiko Nishijima (MWJ) kumamoto@jamstec.go.jp Nutrients Michio Aoyama (MRI) Ayumi Takeuchi (MWJ) maoyama@mri-jma.go.jp DIC Akihiko Murata (JAMSTEC) Yoshiko Ishikawa, Yasuhiro Arii (MWJ) akihiko.murata@jamstec.go.jp Alkalinity Akihiko Murata (JAMSTEC) Fuyuki Shibata, Minoru Kamata (MWJ) akihiko.murata@jamstec.go.jp pH Akihiko Murata (JAMSTEC) Fuyuki Shibata, Minoru Kamata (MWJ) akihiko.murata@jamstec.go.jp CFCs Kenichi Sasaki (JAMSTEC) Kenichi Sasaki (JAMSTEC) ksasaki@jamstec.go.jp ∆14C Yuichiro Kumamoto (JAMSTEC) Yuichiro Kumamoto (JAMSTEC) kumamoto@jamstec.go.jp Radionuclides Michio Aoyama (MRI) Junji Matsushita (MWJ) maoyama@mri-jma.go.jp N2O & CH4 Naohiro Yoshida (TITECH) Osamu Yoshida (Rakuno Gakuen Univ.) naoyoshi@depe.titech.ac.jp XCTD Hiroshi Uchida (JAMSTEC) Satoshi Okumura (GODI) huchida@jamstec.go.jp DMS Ippei Nagao (Nagoya Univ.) Ippei Nagao (Nagiya Univ.) i.nagao@nagoya-u.jp PIM Mitsuo Uematsu (ORI) Yoko Iwamoto (ORI) uematsu@ori.u-tokyo.ac.jp Floats, Drifters Argo float Toshio Suga (JAMSTEC) Tomoyuki Takamori (MWJ) sugat@jamstec.go.jp GODI: Global Ocean Development Inc. JAMSTEC: Japan Agency for Marine-Earth Science and Technology MRI: Meteorological Research Institute, Japan Meteorological Agency MWJ: Marine Works Japan, Ltd. Nagoya Univ.: Nagoya University NIES: National Institute for Environmental Studies Hydrography ORI: Ocean Research Institute, The University of Tokyo Rakuno Gakuen Univ.: Rakuno Gakuen University TITECH: Tokyo Institute of Technology Univ. Tsuluba: University of Tsukuba Univ. Ryukyus: University of the Ryukyus _____________________________________________________________________________________ Table 1.3.1(b): List of principal investigators and persons in charge on the ship for MR07-06 Leg.1 ____________________________________________________________________________________ Item Principal Investigator Person in Charge on the Ship ------------- ------------------------------ ----------------------------------- Underway ADCP Shinya Kouketsu (JAMSTEC) Soichiro Sueyoshi (GODI) skouketsu@jamstec.go.jp Bathymetry Takeshi Matsumoto (U. Ryukyus) Soichiro Sueyoshi (GODI) tak@sci.u-ryukyu.ac.jp Meteorology Kunio Yoneyama (JAMSTEC) Soichiro Sueyoshi (GODI) yoneyamak@jamstec.go.jp T-S Yuichiro Kumamoto (JAMSTEC) Masanori Enoki (MWJ) kumamoto@jamstec.go.jp pCO2 Akihiko Murata (JAMSTEC) Yoshiko Ishikawa, (MWJ) akihiko.murata@jamstec.go.jp Hydrography CTD/O2 Hiroshi Uchida (JAMSTEC) Kenichi Katayama (MWJ) huchida@jamstec.go.jp LADCP Shinya Kouketsu (JAMSTEC) Hiroshi Uchida (JAMSTEC) skouketsu@jamstec.go.jp Salinity Takeshi Kawano (JAMSTEC) Naoko Takahashi (MWJ) kawanot@jamstec.go.jp Oxygen Yuichiro Kumamoto (JAMSTEC) Kimiko Nishijima (MWJ) kumamoto@jamstec.go.jp Nutrients Michio Aoyama (MRI) Ayumi Takeuchi (MWJ) maoyama@mri-jma.go.jp DIC Akihiko Murata (JAMSTEC) Yoshiko Ishikawa, (MWJ) akihiko.murata@jamstec.go.jp Alkalinity Akihiko Murata (JAMSTEC) Fuyuki Shibata, Minoru Kamata (MWJ) akihiko.murata@jamstec.go.jp pH Akihiko Murata (JAMSTEC) Fuyuki Shibata, Minoru Kamata (MWJ) akihiko.murata@jamstec.go.jp CFCs Kenichi Sasaki (JAMSTEC) Kenichi Sasaki (JAMSTEC) ksasaki@jamstec.go.jp ∆14C Yuichiro Kumamoto (JAMSTEC) Yuichiro Kumamoto (JAMSTEC) kumamoto@jamstec.go.jp Radionuclides Michio Aoyama (MRI) Junji Matsushita (MWJ) maoyama@mri-jma.go.jp N2O & CH4 Naohiro Yoshida (TITECH) Osamu Yoshida (Rakuno Gakuen Univ.) naoyoshi@depe.titech.ac.jp XCTD Hiroshi Uchida (JAMSTEC) Satoshi Okumura (GODI) huchida@jamstec.go.jp DMS Ippei Nagao (Nagoya Univ.) Ippei Nagao (Nagiya Univ.) i.nagao@nagoya-u.jp PIM Mitsuo Uematsu (ORI) Yoko Iwamoto (ORI) uematsu@ori.u-tokyo.ac.jp Floats, Drifters Argo float Toshio Suga (JAMSTEC) Tomoyuki Takamori (MWJ) sugat@jamstec.go.jp GODI: Global Ocean Development Inc. JAMSTEC: Japan Agency for Marine-Earth Science and Technology MRI: Meteorological Research Institute, Japan Meteorological Agency MWJ: Marine Works Japan, Ltd. Nagoya Univ.: Nagoya University NIES: National Institute for Environmental Studies Hydrography Univ. Tokyo: The University of Tokyo Univ. Tsuluba: University of Tsukuba Univ. Ryukyus: University of the Ryukyus Univ. Washington: University of Washington ____________________________________________________________________________________ Table 1.3.1(c): List of principal investigators and persons in charge on the ship for MR07-06 Leg.2 _______________________________________________________________________________ Item Principal Investigator Person in Charge on the Ship ------------- ------------------------------ ------------------------------ Underway ADCP Shinya Kouketsu (JAMSTEC) Shinya Okumura (GODI) skouketsu@jamstec.go.jp Bathymetry Takeshi Matsumoto (U. Ryukyus) Shinya Okumura (GODI) tak@sci.u-ryukyu.ac.jp Meteorology Kunio Yoneyama (JAMSTEC) Shinya Okumura (GODI) yoneyamak@jamstec.go.jp T-S Yuichiro Kumamoto (JAMSTEC) Masanori Enoki (MWJ) kumamoto@jamstec.go.jp pCO2 Akihiko Murata (JAMSTEC) Yoshiko Ishikawa (MWJ) akihiko.murata@jamstec.go.jp Hydrography CTD/O2 Hiroshi Uchida (JAMSTEC) Tomoyuki Takamori (MWJ) huchida@jamstec.go.jp LADCP Shinya Kouketsu (JAMSTEC) Hiroshi Uchida (JAMSTEC) skouketsu@jamstec.go.jp Salinity Takeshi Kawano (JAMSTEC) Naoko Takahashi (MWJ) kawanot@jamstec.go.jp Oxygen Yuichiro Kumamoto(JAMSTEC) Kimiko Nishijima (MWJ) kumamoto@jamstec.go.jp Nutrients Michio Aoyama (MRI) Kenichiro Sato (MWJ) maoyama@mri-jma.go.jp DIC Akihiko Murata (JAMSTEC) Yoshiko Ishikawa (MWJ) akihiko.murata@jamstec.go.jp Alkalinity Akihiko Murata (JAMSTEC) Minoru Kamata (MWJ) akihiko.murata@jamstec.go.jp pH Akihiko Murata (JAMSTEC) Minoru Kamata (MWJ) akihiko.murata@jamstec.go.jp CFCs Kenichi Sasaki (JAMSTEC) Kenichi Sasaki (JAMSTEC) ksasaki@jamstec.go.jp ∆14C Yuichiro Kumamoto (JAMSTEC) Akihiko Murata (JAMSTEC) kumamoto@jamstec.go.jp Radionuclides Michio Aoyama (MRI) Junji Matsushita (MWJ) maoyama@mri-jma.go.jp Biology Ken Furuya (Univ. Tokyo) Takuhei Shiozaki (Univ. Tokyo) furuya@fs.a.u-tokyo.ac.jp DOC Masao Uchida (NIES) Yukiko Kuroki (Univ. Tsukuba) uchidama@nies.go.jp Floats, Drifters Argo float Toshio Suga (JAMSTEC) Tomoyuki Takamori (MWJ) sugat@jamstec.go.jp GODI: Global Ocean Development Inc. JAMSTEC: Japan Agency for Marine-Earth Science and Technology MRI: Meteorological Research Institute, Japan Meteorological Agency MWJ: Marine Works Japan, Ltd. NIES: National Institute for Environmental Studies Univ. Tokyo: The University of Tokyo Univ. Tsuluba: University of Tsukuba Univ. Ryukyus: University of the Ryukyus _______________________________________________________________________________ 1.4 SCIENTIFIC PROGRAM AND METHODS (1) Nature and objectives of MR07-K04 and MR07-K06 cruise project It is well known that the oceans play a central role in determining global climate. However heat and material transports in the ocean and their temporal changes have not yet been sufficiently quantified. Therefore, global climate change is not understood satisfactorily. The purposes of this research are to evaluate heat and material transports such as carbon, nutrients, etc. in the North Pacific and to detect their long term changes and basin-scale biogeochemical changes since the 1990s. The MR07-04 cruise is a reoccupation of the eastern part of the hydrographic section called 'WHP-P1', which was observed by an ocean science group of USA in 1985 as a part of WOCE (World Ocean Circulation Experiment) and by a joint group of Canada and Japan in 1999. MR07-06 is a reoccupation of the eastern part of WHP-P1 and the hydrographic section called 'WHP-P14', which was observed by an ocean science group of USA (United States of America) in 1993 also as a part of WOCE (World Ocean Circulation Experiment). The WOCE datasets are included in the data base of CLIVAR (Climate Variability and Predictability) and Carbon Hydrographic Data Office (http://whpo.ucsd.edu/). We will compare physical and chemical properties along section WHP-P1 and P14 with WOCE datasets to detect and evaluate long term changes of the marine environment in the Pacific Ocean. Reoccupations of the WOCE hydrographic sections are now in progress by international cooperation in ocean science community, within the framework of CLIVAR, which is as part of World Climate Research Programme (WCRP) and IOCCP (International Ocean Carbon Coordination Project). Our research is planned as a contribution to these international projects supported by WMO, ICSU/SCOR and UNESCO/IOC, and its results and data will be published by 2009 for worldwide use. The other purposes of this cruise are as follows: 1) to observe surface meteorological and hydrological parameters as a basic data of meteorology and oceanography such as studies on flux exchange, air- sea interaction and so on, 2) to observe sea bottom topography, gravity and magnetic fields along the cruise track to understand the dynamics of ocean plate and accompanying geophysical activities, 3) to observe bio-geochemical parameters to study carbon cycle in the ocean, 4) to observe green house gasses in the atmosphere and the ocean to study their cycle from bio-geochemical aspect. (2) Cruise overview MR07-04 was carried out during the period from July 24 to September 3, 2007. The cruise started from the coast near Hokkaido Japan, and sailed towards east along approximately 47°N. This line was called WHP-P1 and observed by an ocean science group of USA in 1985 as a part of WOCE (World Ocean Circulation Experiment) and by a joint group of Canada and Japan in 1999. The cruise had been designed as a re-occupation of the WHP-P1 stations; however, we could observe only the eastern half of the stations due to an accident. A number of observed stations was 88. MR07-06 cruise was carried out during the period from October 8, 2007 to December 26, 2007. The cruise started also from the coast near Hokkaido. The cruise was designed to observe the rest of WHP-P1 stations (the western part) and WHP-P14N and P14C. A number of stations was 272. At each station, full-depth CTD profile and up to 36 water samples were taken and analyzed. Water samples were obtained from surface to approximately 10 dbar above the bottom with 12-liter Niskin bottles attached to 36-position SBE carousel water sampler. Sampling layer is designed as so-called staggered mesh. The scientists of JAMSTEC and Meteorological Research Institute and the technicians of Marine Works Japan Ltd. (MWJ) were responsible for analyzing water sample for salinity, dissolved oxygen, nutrients, CFCs, total carbon contents, alkalinity, and pH. They also contributed to sampling for total organic carbon, radiocarbon and so on. The technicians of Global Ocean Development Inc. (GODI) had responsibility for a part of underway measurements such as current velocity by Acoustic Doppler Current Profiler (ADCP) geological parameters (topography, geo-magnetic field and gravity), and meteorological parameters. ARGO floats prepared by JAMSTEC and Institute of Ocean Sceinces (Canada) were launched by MWJ technicians and the ship crew. The scientists of Tokyo Institute of Technology joined the cruise for their research on chemical oceanography. A scientist from University of the Ryukyus was a principal investigator for geological parameters (topography, geo-magnetic field and gravity). The scientist from Ocean Research Institute, the university of Tokyo University, Nagoya University, Tsukuba University and University of Washington are also joined the cruise. (3) Cruise narrative MR07-04 R/V Mirai departed Hachinohe (Japan) on July 24, 2007. The hydrographic cast of CTD was started at the first station on July 26. All watchstanders were drilled in the method of sample drawing before the first station. Both propellers got entangled in a fishing net at the station 29 on August 2 (local time). Therefore we were forced to return to the port, Hachinohe, to cut and remove the fishing net. We spent 10 days for the trouble and it made us giving up our observation in the western part of the P1 line, from station 29 to station 60. We restarted the WHP revisit observation at the dateline, station P61. On the way from Hachinohe to station P61, we made a CTD cast specially designed for DMS, Nitrous oxide (N2O), Methane (CH4), Carbonyl sulfide (COS), and related substances at stations 40, 45, 58 and 60,. From stations 41 to 59 (except 45 and 58), we deploy XCTD (1,000m) instead of CTD cast. R/V Mirai arrived at Dutch Harbor (U.S.A.) on September 3, 2007. MR07-06 R/V Mirai departed Hachinohe (Japan) on October 8, 2007. The hydrographic cast of CTD was started at the first station, station 28 of WHP-P1 on October 10. After observing the stations until P01-61, she turned to north to observe the stations of WHP-P14N. She called for Majuro (Republic of the Marshall Islands) on November 20, 2007 (Leg.1). She left Majuro on November 22, 2007 for Auckland (New Zealand) and arrived on December 26, 2007 (Leg.2). We observed 272 stations of a part of WHP-P01 line (47N), WHP-P14N and WHP-P14C. 1.5 MAJOR PROBLEMS AND GOALS NOT ACHIEVED MR07-04 (1) Stations not occupied Both propellers got entangled in a fishing net at the station 29. Therefore we were forced to return to the port, Hachinohe, to cut remove the fishing net. We spent 10 days for the trouble and it made us giving up our observation in the western part of the P1 line, from station 29 to station 60. We restarted the observation at the dateline, station P61. At stations 40, 45, 58 and 60, we made a CTD cast specially designed for DMS, Nitrous oxide (N2O), Methane (CH4), Carbonyl sulfide (COS), and related substances. From stations 41 to 59 (except 45 and 58), we deploy XCTD (1,000m) instead of CTD cast. (2) Misfiring and mistrip The carousel water sampler misfired at station 23 (bottle #15). (3) CTD sensor replacement We encountered to several problems (drift, shift, noise) of CTD sensors and replaced them after the following stations: Sta. 10: primary conductivity sensor Sta. 29: secondary temperature sensor Sta. 44: primary temperature sensor MR07-06 (1) Mistrip The carousel water sampler mistripped at following stations; Stn. P01-040 (Niskin Bottle #10) Stn. P01-054 (Niskin Bottle #10) Stn. P01-077 (Niskin Bottle #27) Stn. P14N-054 (Niskin Bottle #11) Stn. P14N-060 (Niskin Bottle #26) Stn. P14N-063 (Niskin Bottle #11) Stn. P14N-064 (Niskin Bottle #11) Stn. P14N-071 (Niskin Bottle #31) Stn. P14N-092 (Niskin Bottle #24) Stn. P14N-099 (Niskin Bottle #18) Stn. P14N-101 (Niskin Bottle #16) Stn. P14N-103 (Niskin Bottle #5) Stn. P14N-107 (Niskin Bottle #3 and #12) Stn. P14N-126 (Niskin Bottle #30) Stn. P14N-127 (Niskin Bottle #28) Stn. P14C-007 (Niskin Bottle #22) (2) CTD sensor replacement We encountered to several problems (crack, drift, shift, noise) of CTD sensors and replaced them after the following stations: Sta. P01_46: secondary cnductivity sensor Sta. P14N_4: primary and secondary temperature sensors Sta. P14N_33: secondary temperature sensor Sta. P14N_51: secondary conductivity sensor Sta. P14N_74: cast 1: primary and secondary conductivity, and secondary temperature sensors* Sta. P14N_99: primary conductivity sensor Sta. P14N_108: primary conductivity sensor** Sta. P14N_171: secondary conductivity sensor * without secondary temperature and conductivity sensors for Sta. P14N_74 cast 2, and secondary conductivity sensor for Stas. from P14N_75 to P14N_79. ** the broken primary conductivity sensor was replaced after the station P14N_109 cast 1. (3) Thermosalinograph Salinity data from 2007/10/30 3:36 to 2007/11/6 4:34 was lost due to stuffed antifouling devices. 1.6 LIST OF PARTICIPANTS The cruise participants of the cruises are listed in Table 1.3.2 Table 1.3.2(a): List of cruise participants for MR07-04 ______________________________________________________________________________________ Name Responsibility Affiliation ------------------- ------------------------------------- ------------------------ Yasuhiro Arii Carbon Items MWJ Miyo Ikeda Dissolved Oxygen/Water Sampling MWJ Yoshiko Ishikawa Carbon Items MWJ Yoko Iwamoto Aerosol and Fog water ORI Minoru Kamata Carbon Items MWJ Kenichi Katayama CTD/Water Sampling MWJ Kaori Kawana Aerosol and Fog water ORI Kohei Kawano CH4 and N2O/Water Sampling Tokyo Inst. Tech. Takeshi Kawano Chief Scientist/Salinity IORGC/JAMSTEC Kei Kojima Water Sampling MWJ Chihiro Komatsu Water Sampling MWJ Shinya Kouketsu LADCP/ADCP/Water Sampling IORGC/JAMSTEC Yuichiro Kumamoto DO/Thermosalinograph/∆14C IORGC/JAMSTEC Yukiko Kuroki Organic and Inorganic Carbon University of Tsukuba Takashi Makino Water Sampling MWJ Junji Matsushita Radionuclides/Water Sampling MWJ Shunsuke Miyabe Nutrients MWJ Tomohiro Miyabukuro CH4 and N2O/Water Sampling Tokyo Inst. Tech. Dai Motomura Water Sampling MWJ Maki Mukai Water Sampling MWJ Akihiko Murata Carbon Items/Water sampling IORGC/JAMSTEC Ippei Nagao DMS Nagoya University Kimiko Nishijima Dissolved Oxygen/Water Sampling MWJ Satoshi Okumura Meteorology/Geophysics GODI Shinya Okumura Meteorology/Geophysics GODI Ryo Oyama Meteorology/Geophysics GODI Satoshi Ozawa Chief Technologist/CTD/Water Sampling MWJ Katsunori Sagishima CFCs MWJ Kenichi Sasaki CFCs MIO/JAMSTEC Takayoshi Seike Nutrients MWJ Fuyuki Shibata Carbon Items MWJ Yuichi Sonoyama CFCs MWJ Kazuto Suzuki Water Sampling MWJ Naoko Takahashi Salinity/Water Sampling MWJ Tomoyuki Takamori CTD/Water Sampling MWJ Ayumi Takeuchi Nutrients MWJ Tatsuya Tanaka Salinity/Water Sampling MWJ Shigeki Tasaka Radon Gifu University Shoko Tatamisashi CFCs MWJ Hiroshi Uchida CTD/LADCP/Warter Sampling IORGC/JAMSTEC Hirokatsu Uno CTD/Water Sampling MWJ Keisuke Wataki Dissolved Oxygen/Water Sampling MWJ Osamu Yoshida CH4 and N2O/Water Sampling Rakuno Gakuen University GODI: Global Ocean Development Inc. IORGC: Institute of Observational Research for Global Change JAMSTEC: Japan Agency for Marine-earth Sceinece and Technology MIO: Mutsu Institute of Oceanography MWJ: Marine Works Japan Ltd. ORI: Ocean Research Institute, The University of Tokyo Tokyo Inst. Tech.: Tokyo Institute of Technology ______________________________________________________________________________________ Table 1.3.2(b): List of cruise participants for MR07-06 Leg.1 Harumi Ota Meteorology/Geophysics GODI _____________________________________________________________________________________ Name Responsibility Affiliation ------------------- ------------------------------------- ----------------------- Yasuhiro Arii Carbon MWJ Masanori Enoki Dissolved Oxygen/Thermosalinograph MWJ Hironobu Furuya Biology The University of Tokyo Ayaka Hatsuyama Carbon MWJ Mana Hikami Water Sampling MWJ Miyo Ikeda Dissolved Oxygen/Water Sampling MWJ Yoichi Imai Water Sampling JMA Yoshiko Ishikawa Carbon MWJ Kenichi Katayama CTD MWJ Yoshimi Kawai LADCP/Water Sampling IORGC/JAMSTEC Takeshi Kawano Chief Scientist/Salnty/Water Sampling IORGC/JAMSTEC Fujio Kobayashi Salinity MWJ Taketoshi Kodama Biology The University of Tokyo Fumiyoshi Kondo Air-Sea Turbulent CO2 Flux Okayama University Yuichiro Kumamoto Dissolved Oxygen/Water Sampling/14C IORGC/JAMSTEC Nagi Masuda Water Sampling MWJ Junji Matsushita Nutrients MWJ Hiroshi Matsunaga CTD MWJ Kohei Miura Nutrients MWJ Takumi Miyahara Water Sampling MWJ Dai Motomura Water Sampling MWJ Nguyen Van Nguyen Biology The University of Tokyo Kimiko Nishijima Dissolved Oxygen/Water Sampling MWJ Satoshi Okumura Meteorology/Geophysics GODI Shinya Okumura Meteorology/Geophysics GODI Ryo Oyama Meteorology/Geophysics GODI Satoshi Ozawa Chief Technologist/CTD MWJ Katsunori Sagishima CFCs MWJ Kenichi Sasaki CFCs MIO/JAMSTEC Kenichiro Sato Nutrients MWJ Takayoshi Seike Nutrients MWJ Takuhei Shiozaki Biology The University of Tokyo Yuichi Sonoyama CFCs MWJ Naoko Takahashi Salinity MWJ Shoko Tatamisashi CFCs MWJ Tomoyuki Takamori CTD/ARGO MWJ Tatsuya Tanaka Salinity MWJ Hiroshi Uchida CTD/LADCP/Water Sampling IORGC/JAMSTEC Hirokatsu Uno CTD MWJ Kazuho Yoshida Meteorology/Geophysics GODI _____________________________________________________________________________________ Table 1.3.2(b): List of cruise participants for MR07-06 Leg.2 Shinya Okumura Meteorology/Geophysics GODI _____________________________________________________________________________________ Name Responsibility Affiliation ------------------- ------------------------------------- ----------------------- Toshimasa Doi LADCP/Water Sampling IORGC/JAMSTEC Masanori Enoki Dissolved Oxygen/Thermosalinograph MWJ Tsutomu Fujii CTD MWJ Hironobu Furuya Biology The University of Tokyo Ayaka Hatsuyama Carbon MWJ Yukiko Hayakawa Dissolved Oxygen/Water Sampling MWJ Yoichi Imai Water Sampling JMA Yoshiko Ishikawa Carbon MWJ Ryota Ito Water Sampling MWJ Minoru Kamata Carbon MWJ Katsuro Katsumata LADCP/Water Sampling IORGC/JAMSTEC Mikio Kitada Carbon MWJ Taketoshi Kodama Biology The University of Tokyo Misato Koide Water Sampling MWJ Atsushi Kubo Water Sampling MWJ Yukiko Kuroki POC University of Tsukuba Junji Matsushita Radionuclides/Water Sampling MWJ Kohei Miura Nutrients MWJ Akihiko Murata Chief Scientist/Carbon/Water Sampling IORGC/JAMSTEC Nguyen Van Nguyen Biology The University of Tokyo Kimiko Nishijima Dissolved Oxygen/Thermosalinograph MWJ Haruka Nishimura Water Sampling MWJ Ayumi Nomura Water Sampling MWJ Takanori Ojima Water Sampling MWJ Shinya Okumura Meteorology/Geophysics GODI Ryo Oyama Meteorology/Geophysics GODI Satoshi Ozawa Chief Technologist/CTD MWJ Katsunori Sagishima CFCs MWJ Kenichi Sasaki CFCs MIO/JAMSTEC Kenichiro Sato Nutrients MWJ Takayoshi Seike Nutrients MWJ Takuhei Shiozaki Biology The University of Tokyo Yuichi Sonoyama CFCs MWJ Naoko Takahashi Salinity MWJ Shoko Tatamisashi CFCs MWJ Tomoyuki Takamori CTD/ARGO MWJ Tatsuya Tanaka Salinity MWJ Hiroshi Uchida CTD/LADCP/Water Sampling IORGC/JAMSTEC Hirokatsu Uno CTD MWJ Kazuho Yoshida Meteorology/Geophysics GODI GODI: Global Ocean Development Inc. IORGC: Institute of Observational Research for Global Change JAMSTEC: Japan Agency for Marine-earth Sceinece and Technology JMA: Japan Meteorological Agency MIO: Mutsu Institute of Oceanography MWJ: Marine Works Japan Ltd. _____________________________________________________________________________________ 2. UNDERWAY MEASUREMENT 2.1 NAVIGATION AND BATYMETRY 2.1.1 NAVIGATION (1) Personnel Souichiro Sueyoshi(GODI) Satoshi Okumura(GODI) Shinya Okumura(GODI) Kazuho Yoshida (GODI) Harumi Ota (GODI) Ryo Ohyama (GODI) (2) Overview of the equipment Ship's position, speed and course were provided by Radio Navigation System on R/V MIRAI. The system integrates GPS position, Log speed, Gyro heading and other basic data on workstation. Ship's course and speed over ground are calculated from GPS position. The workstation clock is synchronized to reference clock by using NTP (Network Time Protocol). Navigation data, called as "SOJ data", is distributed to client computer every second, and recorded every 60 seconds. Navigation devices are listed below. 1. GPS receiver (2sets): Trimble DS-4000 9-channel receiver, these antennas are located on Navigation deck, port and starboard side. GPS position from each receiver is converted to the position of radar mast. 2. Doppler log: Furuno DS-30, which use three acoustic beam for current measurement 3. Gyrocompass: Tokimec TG-6000, sperry mechanical gyrocompass 4. Reference clock: Symmetricom TymServ2100, GPS time server 5. Workstation: Hewlett-Packard ZX2000 running HP-UX ver.11.22 (3) Data period MR07-04: 07:00, 24 July 2007 to 17:30, 3 September 2007 (UTC) MR07-06 Leg1: 21:30, 7 October 2007 to 21:10, 20 November 2007 (UTC) MR07-06 Leg2: 22:00, 21 November 2007 to 19:10, 25 December 2007 (UTC) Figure 2.2.1-1: Cruise Track of MR07-04 Figure 2.2.1-2: Cruise Track of MR07-06 2.1.2 BATHYMETRY (1) Personnel Takeshi Matsumoto (University of the Ryukyus) Principal Investigator/Not on-board: Souichiro Sueyoshi (GODI) Satoshi Okumura (GODI) Shinya Okumura (GODI) Kazuho Yoshida (GODI) Harumi Ota (GODI) Ryo Ohyama (GODI) (2) Overview of the equipments R/V MIRAI equipped a Multi Beam Echo Sounding system (MBES), SEABEAM 2112.004 (SeaBeam Instruments Inc.) The main objective of MBES survey is collecting continuous bathymetry data along ship's track to make a contribution to geological and geophysical investigations and global datasets. Data interval along ship's track was max 17 seconds at 6,000 m. To get accurate sound velocity of water column for ray-path correction of acoustic multibeam, we used Surface Sound Velocimeter (SSV) data measured at the surface (6.2m depth), and the others depth sound velocity was calculated using temperature and salinity profiles from the nearest CTD data by the equation in Mackenzie (1981). System configuration and performance of SEABEAM 2112.004, Frequency: 12 kHz Transmit beam width: 2 degree Transmit power: 20 kW Transmit pulse length: 3 to 20 msec. Depth range: 100 to 11,000 m Beam spacing: 1 degree athwart ship Swath width: 150 degree (max) 120 degree to 4,500 m 100 degree to 6,000 m 90 degree to 11,000 m Depth accuracy: Within < 0.5% of depth or +/-1m, whichever is greater, over the entire swath. (Nadir beam has greater accuracy; typically within < 0.2% of depth or +/-1m, whichever is greater) (3) Data Period Bathymetric survey was carried out the CTD observation line during the cruise MR07-04: P01-001 on 26 July 2007 to P01-115 on 29 August. 2007 MR07-06 Leg1: P01-028 on 10 October 2007 to P01-61 on 20 October 2007, P14N-001 on 27 October 2007 to P14N-108 on 19 November 2007 MR07-06 Leg2: P14N-109 on 23 November 2007 to P14N-185 on 12 December 2007 P14C-048 on 13 December 2007 to P14C-001 on 22 December 2007 (4) Data processing (4.1) Sound velocity correction The continuous bathymetry data are split into small areas around each CTD station. For each small area, the bathymetry data are corrected using a sound velocity profile calculated from the CTD data in the area. The equation of Mackenzie (1981) is used for calculating sound velocity. The data processing is carried out using "mbbath" command of MBsystem. (4.2) Editing and Gridding Gridding for the bathymetry data are carried out using the HIPS software version 5.4 (CARIS, Canada). Firstly, the bathymetry data during a turn is basically removed before "base surface" is made. A spike noise of each swath data is also removed using "swath editor" and "subset editor". Then the bathymetry data are gridded by "Interpolate" function of the software with following parameters. BASE surface resolution: 50m x 50m Interpolate matrix size: 5 x 5 Minimum number of neighbors for interpolate: 16 Finally, interpolated data is exported as ASCII data, and converted to 250m grid data using "xyz2grd" utility of GMT (Generic Mapping Tool) software. (5) Data Archive Bathymetry data obtained during this cruise was submitted to the JAMSTEC Data Management Division, and archived there. REFERENCE Mackenzie, K.V. (1981): Nine-term equation for the sound speed in the oceans, J. Acoust. Soc. Am., 70 (3), pp 807-812. 2.1.3 Sea surface gravity (1) Personnel Takeshi Matsumoto (University of the Ryukyus) Principal Investigator/Not on-board: Souichiro Sueyoshi (GODI) Satoshi Okumura (GODI) Shinya Okumura (GODI) Kazuho Yoshid (GODI) HarumiOta (GODI) Ryo Ohyama (GODI) (2) Introduction The difference of local gravity is an important parameter in geophysics. We collected gravity data at the sea surface during MR07-04 cruise from 23 Jul. 2007 to 2 Sep. 2007, MR07-06 Leg1 cruise from 7 Oct. 2007 to 19 Nov. 2007, Leg2 cruise from 23 Nov. 2007 to 23 Dec. 2007. (3) Parameters Relative Gravity [mGal] (4) Data Acquisition We have measured relative gravity using LaCoste and Romberg air-sea gravity system II (Micro-G LaCoste, Inc.) during this cruise. To convert the relative gravity to absolute one, we measured gravity, using portable gravity meter (Scintrex gravity meter CG-3M), at Sekinehama and Nakagusuku as reference points. (5) Preliminary Results Absolute gravity is shown in Table 2.2.3-1 Table 2.2.3-1: Absolute gravity table MR07-04 and MR07-06 cruise _________________________________________________________________________________________ Absolute Sea Gravity Gravity Level Draft at Sensor*1 L&R*2 No. Date UTC Port (mGal) (cm) (cm) (mGal) (mGal) --- ----------- ----- ---------- --------- ----- ----- ----------- -------- 1 23/Jul/2007 06:16 Sekinehama 980371.94 261 615 980372.78 12642.60 2*3 02/Oct/2007 07:03 Sekinehama 980371.94 215 603 980372.64 12642.29 3 07/Oct/2007 00:29 Sekinehama 980371.93 281 628 980372.84 12644.04 4*4 25/Jan/2008 03:53 Nakagusuku 979114.70 285 628 979115.62 11386.68 *1: Gravity at Sensor= Absolute Gravity + Sea Level*0.3086/100 + (Draft-530)/100*0.0431 *2: LaCoste and Romberg air-sea gravity system II *3: MR07-05 cruise *4: MR07-07 Leg1 cruise _________________________________________________________________________________________ (6) Data Archive Gravity data obtained during this cruise was submitted to the JAMSTEC Data Management Division, and archived there. 2.1.4 On-board geomagnetic measurement (1) Personnel Takeshi Matsumoto (University of the Ryukyus) Principal Investigator/Not on-board: Souichiro Sueyoshi (GODI) Satoshi Okumura (GODI) Shinya Okumura (GODI) Kazuho Yoshida (GODI) Harumi Ota (GODI) Ryo Ohyama (GODI) (2) Introduction Measurements of magnetic force on the sea are required for the geophysical investigations of marine magnetic anomaly caused by magnetization in upper crustal structure. We measured geomagnetic field using a three-component magnetometer during MR07-04 cruise from 23 Jul. 2007 to 2 Sep. 2007, MR07-06 Leg1 cruise from 7 Oct. 2007 to 19 Nov. 2007, Leg2 cruise from 23 Nov. 2007 to 23 Dec. 2007. (3) Method A shipboard three-component magnetometer system (Tierra Tecnica SFG1214) is equipped on-board R/V Mirai. Three-axis flux-gate sensors with ring-cored coils are fixed on the fore mast. Outputs of the sensors are digitized by a 20-bit A/D converter (1 nT/LSB), and sampled at 8 times per second. Ship's heading, pitch and roll are measured utilizing a Fiber-Optic Gyro installed for Doppler radar system. Ship's position (GPS) and speed data are taken from Navigation data via LAN every second. (4) Data Archive Magnetic force data obtained during this cruise was submitted to the JAMSTEC Data Management Division, and archived there. (5) Remarks For calibration of the ship's magnetic effect, we made a "figure-eight" turn (a pair of clockwise and anti-clockwise rotation). This calibration was carried out as below. MR07-04 cruise: 22 Aug 2007, 06:49 to 07:17 about at 46-59N, 152-31W MR07-06 cruise: 03 Dec. 2007, 02:03 to 02:24 about at 00-03S, 179-20E 2.2 Surface Meteorological Observation (1) Personnel Kunio Yoneyama (JAMSTEC) Satoshi Okumura (GODI) Souichiro Sueyoshi (GODI) Shinya Okumura (GODI) Kazuho Yoshida (GODI) Ryo Ohyama (GODI) Harumi Ota (GODI) (2) Objective As a basic dataset that describes weather conditions during the cruise, surface meteorological observation was continuously conducted. (3) Methods There are two different surface meteorological measurement systems on board the R/V MIRAI. One is the MIRAI surface meteorological observation system (SMET), and the other is the Shipboard Oceanographic and Atmospheric Radiation measurement system (SOAR). Instruments of SMET are listed in Table 2.2.1. All SMET data were collected and processed by KOAC-7800 weather data processor made by Koshin Denki, Japan. Note that although SMET contains rain gauge, anemometer and radiometers in their system, we adopted those data from not SMET but SOAR due to the following reasons; 1) Since SMET rain gauge is located near the base of the mast, there is a possibility that its capture rate might be affected, 2) SOAR's anemometer has better starting threshold wind speed (1 m s-1) comparing to SMET's anemometer (2 m s-1), and 3) SMET's radiometers record data with 10 W/m2 resolution, while SOAR takes high resolution data of 1 W/m2. SOAR system was designed and constructed by the Brookhaven National Laboratory (BNL), USA, for an accurate measurement of solar radiation on the ship. Details of SOAR can be found at http://www.gim.bnl.gov/soar/. SOAR consists of 1) Portable Radiation Package (PRP) that measures short and long wave downwelling radiation, 2) Zeno meteorological system that measures pressure, air temperature, relative humidity, wind speed/direction, and rainfall, and 3) Scientific Computer System (SCS) developed by the National Oceanic and Atmospheric Administration (NOAA), USA, for data collection, management, real- time monitoring, and so on. Information on sensors used here is listed in Table 2.2.2. Table 2.2.1: Instruments and locations of SMET. ________________________________________________________________________________ Location/height Sensor Parameter Manufacturer/type from sea level ------------- ----------------- ---------------------- ------------------- Thermometer*1 air temperature Vaisala, compass deck*2/21 m relative humidity Finland/HMP45A Thermometer sea temperature Sea-Bird Electoronics, 4th deck/-5 m Inc./SBE3S*3 Barometer pressure Setra Systems Inc., captain deck/13 m USA/370 ----------------------------------------------------------------------------- *1 Gill aspirated radiation shield 43408 made by R. M. Young, USA is attached. *2 There are two thermometers at starboard and port sides. *3 Sea surface temperature data were taken from EPCS surface water monitoring system. ________________________________________________________________________________ Table 2.2.2. Instruments and locations of SOAR. ____________________________________________________________________________ Location/height Sensor Parameter Manufacturer/type from sea level ---------- --------------------- ---------------------- --------------- Anemometer wind speed/direction R. M. Young, USA/05106 foremast/25 m Rain gauge rainfall accumulation R. M. Young, USA/50202 foremast/24 m Radiometer short wave radiation Eppley, USA/PSP foremast/24 m long wave radiation Eppley, USA/PIR foremast/24 m ____________________________________________________________________________ (4) Data processing and data format All raw data were recorded every 6 seconds. Datasets produced here are 1-minute mean values (time stamp at the end of the average). They are simple mean of 8 samples (10 samples minus maximum/minimum values) to exclude singular values. Liner interpolation onto missing values was applied only when their interval is less than 5 minutes. Since the thermometers are equipped on both starboard/port sides on the deck, we used air temperature/relative humidity data taken at upwind side. Dew point temperature was produced from relative humidity and air temperature data. No adjustment to sea level values is applied except pressure data. Data are stored as ASCII format and contains following parameters. Time in UTC expressed as YYYYMMDDHHMM, time in Julian day (1.0000 = January 1, 0000Z), longitude (°E), latitude (°N), pressure (hPa), air temperature (°C), dew point temperature (°C), relative humidity (%), sea surface temperature (°C), zonal wind component (m/sec), meridional wind component (m/sec), precipitation (mm/hr), downwelling shortwave radiation (W/m2), and downwelling longwave radiation (W/m2). Missing values are expressed as "9999". (5) Data Quality To ensure the data quality, each sensor was calibrated as follows. Since there is a possibility for fine time resolution data sets to have some noises caused (generated) by turbulence, it is recommended to filter them out (ex. hourly mean) from this 1-minute mean data sets depending on the scientific purpose. T/RH sensor: Temperature and humidity probes were calibrated before/after the cruise by the manufacturer. Certificated accuracy of T/RH sensors are better than ± 0.2°C and ± 2%, respectively. We also checked T/RH values using another calibrated portable T/RH sensor (Vaisala, HMP45A) before and after the cruise. The results are, Temperature (°C) Mean difference between T (SMET) and T (portable) is -0.23±0.22 (°C) at port side, -0.06±0.16 (°C) at starboard side. Relative Humidity (%) Mean difference between RH (SMET) and RH (portable) is 2.6±1.3 (%) at port side, 1.7±1.5 (%) at starboard side. Sea surface temperature sensor: Temperature sensor was calibrated before the cruise at the manufacturer. Certificated accuracy is better than 0.0002°C for MR07-04 cruise and 0.00003°C for MR07-06 cruise, respectively. Pressure sensor: Using calibrated portable barometer (Vaisala, Finland/PTB220, certificated accuracy is better than ± 0.1 hPa), pressure sensor was checked before/after the cruise. Mean difference of SMET pressure sensor and portable sensor is 0.04±0.05 hPa. Precipitation: Before the cruise, we put water into the rain gauge to check their linearity between the indicated values and water amount input. Expected accuracy is better than ± 1 mm corresponding to the sensor's specification. The results are as follows, and data were corrected using this relationship. MR07-04 MR07-06 Leg-1 Leg-2 ------- ------------- ----- minimum input water volume (cc) 0.0 0.0 0.0 minimum measured value (mm) 1.0 1.1 1.1 maximum input water volume (cc) 512.5 512.3 510.0 maximum measured value (mm) 51.8 51.9 51.9 Radiation sensors: Short wave and long wave radiometers were calibrated by the manufacturer, Remote Measurement and Research Company, USA, prior to the cruise (April 2008). (6) Data periods MR07-04 0700 UTC, July 24, 2007 - 0000 UTC, September 2, 2007 MR07-06 Leg-1 2130 UTC, October 7, 2007 - 2110 UTC, November 20, 2007 MR07-06 Leg-2 0100 UTC, November 23, 2007 - 0130 UTC, December 23, 2007 (7) Point of contact Kunio Yoneyama (yoneyamak@jamstec.go.jp) IORGC/JAMSTEC, 2-15, Natsushima, Yokosuka 237-0061, Japan Figure 2.2.1: Time series of (a) air and sea surface temperature, (b) relative humidity, (c) precipitation, (d) pressure, (e) zonal and meridional wind components, and (f) short and long wave radiation for MR07-04 cruise data. Day 205 corresponds to July 24, 2007. Figure 2.2.2: Same as Figure 2.2.1, but for MR07-06 leg 1 cruise. Day 280 corresponds to October 7, 2007. Shading in (c) indicates no data is available during this period. Figure 2.2.3: Same as Figure 2.2.1, but for MR07-06 leg 2 cruise. Day 325 corresponds to November 21, 2007. 2.3 THERMOSALINOGRAPH AND RELATED MEASUREMENTS 9 September 2008 (1) Personnel Yuichiro Kumamoto (JAMSTEC) Kimiko Nishijima (MWJ) Keisuke Wataki (MWJ) Masanori Enoki (MWJ) Miyo Ikeda (MWJ) (2) Objective Our purpose is to measure salinity, temperature, dissolved oxygen, and fluorescence in near-sea surface water during MR07-04 and MR07-06 cruises. (3) Methods The Continuous Sea Surface Water Monitoring System (Nippon Kaiyo Co. Ltd.), including the thermo-salinograph, has five sensors and automatically measures salinity, temperature, dissolved oxygen, and fluorescence in near-sea surface water every one minute. This system is located in the sea surface monitoring laboratory on R/V MIRAI and connected to shipboard LAN system. Measured data, time, and location of the ship were displayed on a monitor and then stored in a data management PC (IBM NetVista 6826-CBJ). The near-surface water was continuously pumped up to the laboratory from about 4 m water depth and flowed into the system through a vinyl-chloride pipe. The flow rate of the surface seawater was controlled by several valves and adjusted to be 12 L/min except for a fluorometer (about 0.5 L/min). The flow rate was measured by two flow meters. Specifications of the each sensor in this system are listed below. a) Temperature and salinity sensors SEACAT THERMOSALINOGRAPH Model: SBE-21, SEA-BIRD ELECTRONICS, INC. Serial number: MR07-04 [25 ~ 31 July]: 2641 (Cal. Date: 9 Feb. 2007) MR07-04 [31 July ~ 1 Sep]: 3126 (Cal. Date: 1 Sep. 2006) MR07-06: 2641 (Cal. Date: 9 Feb. 2007) Measurement range: Temperature -5 to +35°C, Salinity 0 to 6.5 S m-1 Accuracy: Temperature 0.01°C 6month-1 , Salinity 0.001 S m-1 month-1 Resolution: Temperatures 0.001°C, Salinity0.0001 S m-1 b) Bottom of ship thermometer Model: SBE 3S, SEA-BIRD ELECTRONICS, INC. Serial number: MR07-04: 2175 (Cal. Date: 15 Feb. 2007) MR07-06: 2607 (Cal. Date: 10 Aug. 2007) Measurement range: -5 to +35°C Resolution: ±0.001°C Stability: 0.002°C year-1 c) Dissolved oxygen sensor Model: 2127A, HACH ULTRA ANALYTICS JAPAN, INC. Serial number: 47477 Measurement range: 0 to 14 ppm Accuracy: ±1% at 5°C of correction range Stability: 1% month-1 d) Fluorometer Model: 10-AU-005, TURNER DESIGNS Serial number: 5562 FRXX Detection limit: 5 ppt or less for chlorophyll-a Stability: 0.5% month-1 of full scale e) Flow meter Model: EMARG2W, Aichi Watch Electronics LTD. Serial number: 8672 Measurement range: 0 to 30 l min-1 Accuracy: ±1% Stability: ±1% day-1 (4) Measurements Periods of measurement, maintenance, and problems during MR07-04 and MR07-06 are listed in Table 2.3.1. During MR07-04, SEB-21 was exchanged from S/N 2641 to S/N 3126 on July 31. During MR07-06, an antifoulant (antibiotic) device to prevent growth of aquatic organisms was detached from the SBE-21 sensors due to a problem on November 7. Due to this problem salinity data were lost between October 30 and November 7. (5) Calibrations (5.1) Comparison with bottle data We collected the surface seawater samples for salinity sensor calibration (Table 2.3.2 and 2.3.3). The seawaters were collected approximately twice a day using a 250ml brown grass bottle. The samples were stored in the sea surface monitoring laboratory and then measured using the Guildline 8400B at the end of the legs after all the measurements of the hydrocast bottle samples (see section 3.2). (5.2) Sensor calibrations The sensors for temperature and salinity were calibrated before the cruise. After the cruise the sensors will be calibrated again in order to evaluate drifts of measurements during the cruise. The results of the calibrations are available via our web page, http://www.jamstec.go.jp/cruisedata/mirai/e/index.html. (6) Date archive Quality controlled data and meta-data are available via our web page, http://www.jamstec.go.jp/cruisedata/mirai/e/index.html. Table 2.3.1: Events list of the thermo-salinograph during MR07-04 and MR07-06 _________________________________________________________________________________ Cruise Date [UTC] Time [UTC] Event Remarks ------- ---------- ----------- ----------------------- -------------------- MR07-04 25-July-07 10:07 All the measurements Departure started. Hachinohe 31-July-07 20:49 All the measurements stopped. Checked SBE21(S/N2641) 31-July-07 22:19 All the measurements started Exchanged SBE21 (S/N2641 -> S/N3126) 02-Aug.-07 23:15~23:16 Failure of data Unknown problem storage for location. 08-Aug.-07 01:01 All the measurements Arrival stopped. Hachinohe 10-Aug.-07 00:46 All the measurements Departure started. Hachinohe 01-Sep.-07 17:55 All the measurements Arrival stopped. Dutch Harbor MR07-06 9-Oct.-07 02:17 All the measurements Departure started. Hachinohe (Leg-1 start) 05-Nov.-07 14:31~14:35 Lost of all the data. Due to a tripping of a circuit breaker 30-Oct.-07 03:36 Lost of salinity data. Due to a problem 07-Nov.-07 04:08 of the antibiotic device 07-Nov.-07 04:09~05:04 Lost of all the data. Reboot of the data management PC 18-Nov.-07 04:35 Failure of RMT tempera- Due to a noise in ture data archive. the data 19-Nov.-07 07:36 All the measurements Arrival Majuro stopped. (Leg-1 end) 23-Nov.-07 02:00 All the measurements Departure Majuro started. (Leg-2 start) 23-Dec.-07 01:28 All the measurements Arrival Auckland stopped. (Leg-2 end) _________________________________________________________________________________ Table 2.3.2: Comparison of the sensor salinity with the bottle salinity during MR07-04. _________________________________________________________________________________ Sensor Bottle Date Time salinity salinity Difference [UTC] [UTC] Latitude Longitude [PSS-78] [PSS-78] [Sen. - Bot.] --------- ----- ------------ ------------- ------- -------- ------------- 2007/7/25 11:45 40-59.56800N 143-01.10930E 33.5532 33.5435 0.0097 2007/7/25 22:50 41-25.73860N 145-33.00760E 33.1134 33.1092 0.0042 2007/7/26 7:50 42-48.17710N 145-27.19090E 33.0332 32.9148 0.1184 2007/7/26 18:35 42-39.75580N 145-41.41540E 32.8070 32.7676 0.0394 2007/7/27 6:57 42-10.79830N 146-05.03190E 32.7934 32.7528 0.0406 2007/7/27 18:26 41-52.48810N 146-18.41610E 32.6836 32.6956 -0.0120 2007/7/28 6:25 41-42.78640N 146-26.08430E 32.7105 32.7144 -0.0039 2007/7/28 17:42 41-21.42700N 146-41.11320E 32.7118 32.7226 -0.0108 2007/7/29 6:17 40-50.82040N 147-04.04230E 32.7539 32.8174 -0.0635 2007/7/29 18:17 40-07.44810N 147-33.93700E 34.3895 34.3785 0.0110 2007/7/30 6:15 39-41.50140N 147-55.39620E 34.3704 34.3733 -0.0029 2007/7/30 18:49 40-19.26800N 148-52.31960E 34.4994 34.4946 0.0048 2007/7/31 6:58 40-55.49780N 149-51.04410E 34.4920 34.4889 0.0031 2007/7/31 19:15 41-33.67610N 150-52.33380E 33.0052 32.9972 0.0080 2007/8/1 7:01 42-20.17860N 152-05.04200E 33.2326 33.2204 0.0122 2007/8/1 17:05 42-40.53890N 152-42.26540E 33.0865 33.0802 0.0063 2007/8/2 3:43 42-46.24720N 152-52.61200E 33.0909 33.086 0.0049 2007/8/2 14:40 42-16.33730N 153-02.98470E 33.7921 33.7798 0.0123 2007/8/3 11:06 41-09.40780N 153-00.48910E 34.5137 34.5066 0.0071 2007/8/3 21:09 40-32.21620N 153-00.60930E 33.7968 33.8032 -0.0064 2007/8/4 8:43 40-00.34550N 153-01.61040E 34.1606 34.1553 0.0053 2007/8/4 23:16 40-11.85680N 153-09.64890E 33.8481 33.844 0.0041 2007/8/5 7:25 40-12.99160N 152-33.21310E 33.9156 33.9139 0.0017 2007/8/5 22:56 40-18.83730N 150-22.60930E 33.5227 33.5537 -0.0310 2007/8/6 8:29 40-21.15240N 148-57.04860E 33.7495 33.712 0.0375 2007/8/6 22:49 40-24.15980N 147-13.70230E 34.4521 34.4463 0.0058 2007/8/7 8:34 40-26.14660N 146-01.54310E 33.6041 33.5854 0.0187 2007/8/10 3:29 40-30.47580N 148-30.41270E 32.6756 32.6924 -0.0168 2007/8/10 15:38 41-45.96810N 152-21.06700E 33.0687 33.0622 0.0065 2007/8/11 2:43 43-18.92240N 155-37.71560E 33.9769 33.9437 0.0332 2007/8/11 7:34 44-05.47490N 156-59.82140E 32.8430 32.8564 -0.0134 2007/8/11 21:08 46-15.85980N 160-54.30660E 32.9301 32.9136 0.0165 2007/8/12 10:23 47-00.16990N 163-58.87420E 32.7841 32.8029 -0.0188 2007/8/12 20:49 46-59.16850N 166-44.32290E 32.8503 32.8436 0.0067 2007/8/13 10:17 47-00.34900N 171-07.85130E 32.7411 32.7608 -0.0197 2007/8/13 22:10 47-00.12300N 175-35.01600E 32.8015 32.8139 -0.0124 2007/8/14 12:08 46-59.93210N 178-18.23620E 32.7989 32.7947 0.0042 2007/8/14 21:53 47-00.83360N 179-26.98080E 32.7283 32.7244 0.0039 2007/8/15 9:26 46-59.51960N 178-18.91400W 32.6862 32.6819 0.0043 2007/8/15 21:48 47-00.07570N 176-37.54620W 32.5401 32.5288 0.0113 2007/8/16 9:45 47-00.04090N 174-56.44210W 32.6165 32.6103 0.0062 2007/8/16 21:05 46-59.78510N 172-42.64610W 32.7305 32.7317 -0.0012 2007/8/17 8:58 47-00.42840N 171-15.40150W 32.6261 32.6201 0.0060 2007/8/17 20:13 46-59.66060N 169-20.49430W 32.5481 32.5443 0.0038 2007/8/18 8:55 47-00.45780N 167-05.29050W 32.6200 32.6132 0.0068 2007/8/18 21:57 47-01.17270N 164-59.92870W 32.7182 32.7068 0.0114 2007/8/19 7:47 47-00.44260N 163-43.31850W 32.6417 32.6403 0.0014 2007/8/19 20:06 47-00.56460N 161-29.41830W 32.6488 32.6454 0.0034 2007/8/20 8:42 46-59.45290N 159-40.89610W 32.8259 32.7851 0.0408 2007/8/20 19:06 47-00.21960N 158-08.58960W 32.6516 32.6507 0.0009 2007/8/21 8:05 46-59.50660N 155-51.80530W 32.6803 32.6594 0.0209 2007/8/21 20:49 47-00.05950N 153-38.13320W 32.6733 32.6492 0.0241 2007/8/22 8:51 46-57.98700N 152-03.39390W 32.5771 32.5925 -0.0154 2007/8/22 21:01 46-59.89670N 151-37.39790W 32.5729 32.5669 0.0060 2007/8/23 7:05 46-59.11440N 150-17.59340W 32.5377 32.5289 0.0088 2007/8/23 19:37 47-00.48950N 148-02.17190W 32.4434 32.4448 -0.0014 2007/8/24 7:13 46-59.97990N 145-48.73560W 32.4713 32.3907 0.0806 2007/8/24 19:29 46-59.56400N 143-40.41810W 32.3720 32.3577 0.0143 2007/8/25 6:47 46-59.96520N 141-54.50520W 32.3190 32.3614 -0.0424 2007/8/25 21:10 47-00.04030N 139-04.06470W 32.4736 32.4163 0.0573 2007/8/26 7:39 46-59.23350N 137-29.04750W 32.4100 32.4496 -0.0396 2007/8/26 17:20 46-59.98240N 135-43.90950W 32.4774 32.4267 0.0507 2007/8/27 5:59 46-59.30070N 133-27.95720W 32.4447 32.4419 0.0028 2007/8/27 17:02 47-00.38230N 131-13.71710W 32.3672 32.3549 0.0123 2007/8/28 6:43 47-00.11040N 128-38.31500W 32.3364 32.2963 0.0401 2007/8/28 18:37 47-00.30230N 126-28.19600W 32.0321 32.1002 -0.0681* 2007/8/29 6:10 46-55.65720N 124-58.92520W 31.8860 31.581 0.3050* 2007/8/29 16:56 48-01.70010N 127-57.81150W 31.8923 32.3276 -0.4353* 2007/8/30 7:34 49-37.43780N 132-44.53330W 32.2969 32.0908 0.2061* _________________________________________________________________________________ * Difference between the sensor and the bottle salinity is large. Table 2.3.3: Comparison of the sensor salinity with the bottle salinity during MR07-06 __________________________________________________________________________________ Sensor Bottle Date Time salinity salinity Difference [UTC] [UTC] Latitude Longitude [PSS-78] [PSS-78] [Sen. - Bot.] --------- ----- ------------ ------------- ------- -------- ------------- 2007/10/9 5:25 40-32.06180N 144-33.13440E 33.8540 33.8458 0.0082 2007/10/9 14:12 40-22.40990N 146-42.40840E 33.6539 33.7204 -0.0665* 2007/10/10 2:55 41-05.85970N 150-18.13910E 33.0454 33.0327 0.0127 2007/10/10 17:23 42-20.76330N 152-09.03380E 33.0246 33.0196 0.0050 2007/10/11 6:36 43-04.88550N 153-19.58350E 32.8880 32.8815 0.0065 2007/10/11 18:27 44-04.74300N 154-59.84680E 32.6292 32.6202 0.0090 2007/10/12 6:42 44-20.23280N 155-24.25840E 32.6718 32.6882 -0.0164 2007/10/12 18:48 45-04.93350N 156-38.62630E 32.6208 32.6191 0.0017 2007/10/13 6:20 46-05.23470N 158-20.15860E 32.6245 32.6095 0.0150 2007/10/13 17:47 46-30.35720N 159-06.53620E 32.6256 32.6067 0.0189 2007/10/14 6:03 47-01.02970N 160-08.89530E 32.6805 32.6503 0.0302 2007/10/14 17:40 46-59.52310N 162-15.61480E 32.6576 32.6517 0.0059 2007/10/15 5:48 47-00.14140N 164-21.29860E 32.7218 32.7181 0.0037 2007/10/15 18:09 46-59.07380N 165-37.89780E 32.7204 32.7177 0.0027 2007/10/16 5:45 46-57.67950N 166-43.18590E 32.7198 32.7006 0.0192 2007/10/16 17:21 46-59.41470N 168-22.56610E 32.6269 32.6230 0.0039 2007/10/17 4:43 47-00.57730N 169-05.85870E 32.6415 32.6348 0.0067 2007/10/17 16:50 46-58.65870N 169-48.59680E 32.6433 32.6435 -0.0002 2007/10/18 4:37 46-59.83390N 170-28.31700E 32.6664 32.6637 0.0027 2007/10/18 17:37 47-00.36100N 172-11.21260E 32.6925 32.6908 0.0017 2007/10/19 4:00 47-00.24210N 173-49.77000E 32.6660 32.6612 0.0048 2007/10/19 17:22 46-59.80860N 176-05.82360E 32.6682 32.6711 -0.0029 2007/10/20 4:52 46-59.40840N 177-23.84440E 32.7044 32.6961 0.0083 2007/10/20 17:22 47-00.00850N 179-26.22310E 32.7052 32.6981 0.0071 2007/10/21 4:47 47-59.94950N 178-58.96240E 32.7126 32.7113 0.0013 2007/10/21 16:29 48-59.35410N 178-58.98940E 32.7462 32.7458 0.0004 2007/10/22 5:27 50-00.83360N 178-58.88290E 32.7591 32.7558 0.0033 2007/10/22 16:31 50-28.96300N 179-17.18900E 32.7410 32.7375 0.0035 2007/10/23 4:21 50-56.90210N 179-34.72020E 32.7865 32.7856 0.0009 2007/10/23 17:34 51-49.39240N 179-48.31570W 33.1172 33.0838 0.0334 2007/10/24 4:31 52-16.13690N 178-58.41500W 33.0384 33.0340 0.0044 2007/10/24 16:44 53-29.70310N 178-14.46000W 33.0212 32.9384 0.0828* 2007/10/25 4:14 54-29.63280N 177-33.24850W 32.9897 33.0030 -0.0133 2007/10/25 16:43 55-46.93320N 176-39.18100W 32.9090 32.8842 0.0248 2007/10/26 5:22 56-58.85310N 175-40.15170W 32.6355 32.6284 0.0071 2007/10/26 18:01 57-59.76550N 174-49.90480W 32.5895 32.5258 0.0637* 2007/10/27 4:57 58-08.08730N 174-44.48860W 32.5030 32.3429 0.1601* 2007/10/27 17:19 56-30.05810N 176-03.67350W 32.5951 32.7054 -0.1103* 2007/10/28 4:39 54-08.81850N 177-54.30220W 32.9045 32.9649 -0.0604* 2007/10/28 13:05 52-32.19380N 179-08.82310W 33.0417 33.0057 0.0360 2007/10/29 4:01 50-14.37020N 179-37.14930E 32.7248 32.7183 0.0065 2007/10/29 14:42 47-41.52110N 179-02.67540E 32.7274 32.6862 0.0412 2007/10/30 3:41 46-53.64970N 179-22.82010E - 32.6969 - 2007/10/30 15:14 45-59.16150N 179-01.56400E - 32.6628 - 2007/10/31 3:35 45-00.74700N 178-57.16110E - 32.8870 - 2007/10/31 15:15 44-25.17970N 178-59.33940E - 32.9982 - 2007/11/1 3:39 43-25.96290N 179-02.30580E - 33.0939 - 2007/11/1 15:26 42-28.59190N 178-59.11440E - 33.4875 - 2007/11/2 3:12 41-23.64650N 179-01.51310E - 33.8685 - 2007/11/2 15:27 40-20.81390N 178-59.78120E - 33.9810 - 2007/11/3 3:24 39-26.10410N 179-02.86940E - 33.9847 - 2007/11/3 15:45 38-23.33390N 178-58.98450E - 34.2733 - 2007/11/4 3:31 37-18.29470N 179-01.24320E - 34.1793 - 2007/11/4 16:00 35-59.85240N 179-00.06330E - 34.3576 - 2007/11/5 3:58 35-00.12920N 179-00.07790E - 34.3425 - 2007/11/5 15:55 33-44.35400N 178-59.55440E - 34.3342 - 2007/11/6 3:11 32-29.25280N 178-59.81090E - 34.4613 - 2007/11/6 15:20 31-30.00990N 179-01.02830E - 34.9858 - 2007/11/7 3:58 30-29.46880N 178-58.82510E - 34.8471 - 2007/11/7 15:23 29-29.82960N 178-59.54800E 35.0656 35.0616 0.0040 2007/11/8 3:31 28-29.09130N 178-59.81260E 35.1072 35.1020 0.0052 2007/11/8 15:09 27-29.82050N 179-00.43770E 35.1408 35.1350 0.0058 2007/11/9 3:38 26-29.73090N 179-00.05290E 35.1328 35.1256 0.0072 2007/11/9 15:02 26-01.48300N 179-09.89370E 35.2352 35.2285 0.0067 2007/11/10 3:35 25-55.53690N 179-35.36160E 35.1871 35.1823 0.0048 2007/11/10 14:53 25-37.38100N 179-08.77730E 35.1945 35.1835 0.0110 2007/11/11 3:32 25-00.00200N 179-00.87020E 35.1259 35.1160 0.0099 2007/11/11 15:07 24-00.25110N 178-59.54920E 35.1751 35.1667 0.0084 2007/11/12 3:25 23-00.17370N 178-59.73550E 35.1788 35.1675 0.0113 2007/11/12 15:29 22-00.68720N 178-59.79810E 35.2859 35.2776 0.0083 2007/11/13 3:54 20-40.66570N 178-59.76420E 35.2590 35.2487 0.0103 2007/11/13 15:15 19-30.66360N 179-00.02710E 34.9384 34.9276 0.0108 2007/11/14 3:29 18-30.92670N 179-00.39380E 34.9828 34.9705 0.0123 2007/11/14 15:43 17-31.50610N 178-59.80200E 34.7915 34.7802 0.0113 2007/11/15 4:07 16-24.89740N 178-59.54480E 34.6641 34.6546 0.0095 2007/11/15 15:30 15-30.91970N 178-59.09970E 34.7727 34.7595 0.0132 2007/11/16 3:36 14-30.31750N 178-58.52030E 34.7215 34.7105 0.0110 2007/11/16 15:14 13-30.46350N 178-59.04190E 34.6934 34.6809 0.0125 2007/11/17 3:25 12-31.37000N 178-59.21560E 34.5697 34.5586 0.0111 2007/11/17 15:21 11-31.21370N 178-59.68420E 34.3699 34.3584 0.0115 2007/11/18 4:03 10-30.99360N 178-59.81610E 34.3508 34.3394 0.0114 2007/11/18 15:29 09-29.79300N 178-49.30000E 34.2541 34.2427 0.0114 2007/11/19 4:12 08-45.75560N 178-59.25940E 34.0907 34.0779 0.0128 2007/11/19 7:34 08-30.49010N 178-59.17670E 34.0624 34.0496 0.0128 2007/11/23 6:21 08-28.64970N 177-35.78940E 34.3121 34.2969 0.0152 2007/11/23 20:57 08-30.58210N 178-59.31190E 34.2402 34.2239 0.0163 2007/11/24 4:35 08-15.65310N 178-59.95810E 34.2931 34.2779 0.0152 2007/11/24 15:11 07-44.86660N 179-00.67490E 34.3735 34.3571 0.0164 2007/11/25 5:25 06-59.91330N 179-00.06250E 34.9224 34.9055 0.0169 2007/11/25 15:03 06-43.39460N 179-01.10810E 34.9023 34.8856 0.0167 2007/11/26 9:02 05-48.04660N 179-00.02110E 34.6940 34.6773 0.0167 2007/11/26 19:05 05-26.90940N 178-59.91100E 34.8380 34.8221 0.0159 2007/11/27 3:34 04-59.55490N 178-59.60990E 34.9097 34.8895 0.0202 2007/11/27 15:19 04-28.97130N 179-00.63150E 35.1440 35.1281 0.0159 2007/11/28 3:45 03-59.53280N 179-00.29860E 35.1021 35.0869 0.0152 2007/11/28 15:44 03-30.23710N 179-00.16020E 35.1012 35.0856 0.0156 2007/11/29 3:36 03-00.21240N 179-00.13510E 35.1367 35.1212 0.0155 2007/11/29 16:01 02-18.22210N 179-00.16430E 35.1347 35.1212 0.0135 2007/11/30 3:55 01-46.88070N 178-59.98650E 35.1377 35.1235 0.0142 2007/11/30 15:31 01-15.66770N 179-00.43110E 35.1435 35.1276 0.0159 2007/12/1 3:46 00-44.30730N 178-59.59540E 35.1914 35.1760 0.0154 2007/12/1 15:37 00-14.79480N 178-59.80660E 35.2090 35.1943 0.0147 2007/12/2 4:15 00-14.67970S 178-59.64810E 35.2218 35.2073 0.0145 2007/12/2 12:41 00-10.57770S 179-06.94120E 35.2325 35.2174 0.0151 2007/12/3 4:52 00-12.28510S 179-04.73820E 35.2249 35.2099 0.0150 2007/12/3 14:57 00-44.44420S 179-00.38430E 35.2623 35.2469 0.0154 2007/12/4 3:20 01-14.79930S 178-59.80360E 35.3369 35.3212 0.0157 2007/12/4 15:34 01-44.20500S 178-59.90450E 35.4360 35.4201 0.0159 2007/12/5 3:22 02-17.59460S 178-59.93920E 35.6036 35.5869 0.0167 2007/12/5 15:24 02-53.72300S 178-59.76740E 35.6056 35.5887 0.0169 2007/12/6 3:06 03-27.43530S 179-00.16390E 35.7017 35.6843 0.0174 2007/12/6 15:36 04-00.42580S 179-00.22410E 35.6937 35.6779 0.0158 2007/12/7 3:32 04-30.49320S 179-00.53770E 35.7250 35.7082 0.0168 2007/12/7 15:32 04-59.93530S 179-00.01310E 35.5754 35.5597 0.0157 2007/12/8 3:45 06-00.49190S 179-00.46560E 35.3242 35.3077 0.0165 2007/12/8 14:36 06-53.23310S 178-59.79630E 34.9645 34.9512 0.0133 2007/12/9 4:03 08-00.07870S 178-59.79360E 34.9440 34.9289 0.0151 2007/12/9 15:36 09-00.39210S 178-59.93910E 34.8335 34.8182 0.0153 2007/12/10 3:40 10-00.45970S 178-59.86400E 34.9014 34.8881 0.0133 2007/12/10 15:18 11-13.93150S 178-59.74590E 34.7253 34.7089 0.0164 2007/12/11 3:33 12-30.37470S 178-59.91460E 34.6997 34.7019 -0.0022 2007/12/11 15:51 13-46.37280S 179-00.26670E 34.7411 34.7252 0.0159 2007/12/12 4:00 15-22.73890S 178-59.73240E 34.5721 34.5526 0.0195 2007/12/12 15:19 16-12.74140S 177-54.43780E 34.4854 34.4725 0.0129 2007/12/13 4:35 18-00.97310S 176-45.86950E 34.5336 34.5170 0.0166 2007/12/13 14:24 18-50.60070S 177-46.34680E 34.6658 34.6499 0.0159 2007/12/14 3:17 18-55.97910S 177-42.97910E 34.6754 34.6600 0.0154 2007/12/14 15:33 19-28.61270S 177-27.00180E 34.6839 34.6687 0.0152 2007/12/15 3:23 20-07.58350S 177-31.91270E 34.8697 34.8541 0.0156 2007/12/15 14:34 20-49.63040S 177-33.64870E 34.7734 34.7594 0.0140 2007/12/16 3:13 21-27.06220S 177-28.28690E 34.7654 34.7500 0.0154 2007/12/16 14:27 22-35.48470S 177-15.81440E 35.1803 35.1668 0.0135 2007/12/17 3:34 23-28.79280S 177-06.59720E 35.2719 35.2571 0.0148 2007/12/17 15:22 24-33.84780S 176-55.51780E 35.3974 35.3832 0.0142 2007/12/18 3:14 25-40.20740S 176-44.22250E 35.3818 35.3685 0.0133 2007/12/18 15:32 26-32.00690S 176-35.73230E 35.5411 35.5272 0.0139 2007/12/19 3:17 27-42.58850S 176-23.83980E 35.3077 35.2935 0.0142 2007/12/19 14:58 28-42.40730S 176-13.37440E 35.4757 35.4621 0.0136 2007/12/20 3:33 29-47.61200S 175-58.31910E 35.5968 35.5770 0.0198 2007/12/20 15:37 30-52.84490S 175-51.55180E 35.6651 35.6505 0.0146 2007/12/21 3:21 31-44.20450S 175-43.19030E 35.6629 35.6484 0.0145 2007/12/21 15:40 32-49.34980S 175-32.03160E 35.7132 35.6991 0.0141 2007/12/22 3:07 33-42.10310S 175-23.62260E 35.6878 35.6729 0.0149 2007/12/22 15:06 35-01.27420S 175-09.08010E 35.7422 35.7286 0.0136 2007/12/23 1:20 35-33.05740S 175-08.87520E 35.6953 35.6812 0.0141 * Difference between the sensor and the bottle salinity is large. __________________________________________________________________________________ 2.4 UNDERWAY pCO2 9 November 2008 (1) Personnel Akihiko Murata (IORGC, JAMSTEC) Yoshiko Ishikawa (MWJ) Yasuhiro Arii (MWJ) Mikio Kitada (MWJ) (2) Objectives Concentrations of CO2 in the atmosphere are now increasing at a rate of 1.5 ppmv y-1 due to human activities such as burning of fossil fuels, deforestation, cement production, etc. It is an urgent task to estimate as accurately as possible the absorption capacity of the ocean against the increased atmospheric CO2, and to clarify the mechanism of the CO2 absorption, because the magnitude of the predicted global warming depends on the levels of CO2 in the atmosphere, and because the ocean currently absorbs 1/3 of the 6 Gt of carbon emitted into the atmosphere each year by human activities. In the P1 and P14 revist cruises, we were aimed at quantifying how much anthropogenic CO2 is absorbed in the surface ocean in the Pacific. For the purpose, we measured pCO2 (partial pressures of CO2) in the atmosphere and in the surface seawater. (3) Apparatus and shipboard measurement Continuous underway measurements of atmospheric and surface seawater pCO2 were made with the CO2 measuring system (Nippon ANS, Ltd) installed in the R/V Mirai of JAMSTEC. The system comprises of a non-dispersive infrared gas analyzer (NDIR; BINOS(r) model 4.1, Fisher-Rosemount), an air-circulation module and a showerhead-type equilibrator. To measure concentrations (mole fraction) of CO2 in dry air (xCO2a), air sampled from the bow of the ship (approx. 30 m above the sea level) was introduced into the NDIR through a dehydrating route with an electric dehumidifier (kept at ~2°C), a Perma Pure dryer (GL Sciences Inc.), and a chemical desiccant (Mg(ClO4)2). The flow rate of the air was 500 ml min- 1. To measure surface seawater concentrations of CO2 in dry air (xCO2s), the air equilibrated with seawater within the equilibrator was introduced into the NDIR through the same flow route as the dehydrated air used in measuring xCO2a. The flow rate of the equilibrated air was 600 - 800 ml min-1. The seawater was taken by a pump from the intake placed at the approx. 4.5 m below the sea surface. The flow rate of seawater in the equilibrator was 500 - 800 ml min-1. The CO2 measuring system was set to repeat the measurement cycle such as 4 kinds of CO2 standard gases (Table 2.4.1), xCO2a (twice), xCO2s (7 times). This measuring system was run automatically throughout the cruise by a PC control. (4) Quality control Concentrations of CO2 of the standard gases are listed in Table 2.4.1, which were calibrated by the JAMSTEC primary standard gases. The CO2 concentrations of the primary standard gases were calibrated by C.D. Keeling of the Scripps Institution of Oceanography, La Jolla, CA, USA. Since differences of concentrations of the standard gases between before and after the cruise were allowable (< 0.1 ppmv), the averaged concentrations (Table 2.4.1) were adopted for the subsequent calculations. In actual shipboard observations, the signals of NDIR usually reveal a trend. The trends were adjusted linearly using the signals of the standard gases analyzed before and after the sample measurements. Effects of water temperature increased between the inlet of surface seawater and the equilibrator on xCO2s were adjusted based on Gordon and Jones (1973), although the temperature increases were slight, being ~ 0.3°C. We checked values of xCO2a and xCO2s by examining signals of the NDIR on recorder charts, and by plotting the xCO2a and xCO2s as a function of sequential day, longitude, sea surface temperature and sea surface salinity. REFERENCE Gordon, L. I. and L. B. Jones (1973) The effect of temperature on carbon dioxide partial pressure in seawater. Mar. Chem., 1, 317-322. Table 2.4.1: Concentrations of CO2 standard gases used in (a) P1 and (b) P14 revisit cruises _____________________________________ (a) Cylinder no. Concentrations (ppmv) CQB09356 289.77 CQB15439 349.02 CQB15432 394.23 CQB09375 439.75 (b) Cylinder no. Concentrations (ppmv) CQB06555 270.02 CQB19242 330.40 CQB15437 369.28 CQB09327 419.68 _____________________________________ 2.5 Acoustic Doppler Current Profiler 5 November 2008 (1) Personnel Shinya Kouketsu (JAMSTEC) Hiroshi Uchida (JAMSTEC) Satoshi Okumura (GODI) Shinya Okumura (GODI) Ryo Oyama (GODI) Kazuho Yoshida (GODI) (2) Instruments and method The instrument used was an RDI 76.8 kHz unit, hull-mounted on the centerline and approximately 23 m aft of the bow at the water line. The firmware version was 5.59 and the data acquisition software was the RDI VMDAS Version. 1.4. The Operation was made from the first CTD station to the last CTD station in each leg. It was continued to the Auckland port in the third leg. The instrument was used in the water-tracking mode during the most of operations, recording each ping raw data in 8 m x 100 bins from about 23 m to 735 m in deep. Typical sampling interval was 3.5 seconds. Bottom track mode was added in the easternmost shallow water region. GPS gave the navigation data. Two kinds of compass data were recorded. One was the ship's gyrocompass which is connected the ADCP system directory, were stored with the ADCP data. Current field based on the gyrocompass was used to check the operation and the performance on board. Another compass used was the Inertial Navigation Unit (INU), DRU-H, Honeywell Inc. Its accuracy is 1.0 mile (about 0.056 degree) and had already set on zero bias before the beginning of the cruise. The INU compass data were stored independently, and were combined with the ADCP data after the cruise. (3) Performance of the ADCP data The performance of the ADCP instrument was almost good: on streaming, profiles usually reached to about 600 m. Profiles were rather bad on CTD station. The profiles were sometimes obtained from 200 m to 500 m. In these cases the ADCP signal was weak typically at about 350 m in deep. It is probably due to the babbles from the bow-thruster. Echo intensities for each legs changed due to environment of sea (Fig. 2.5.1), although the intensities were not different by each beams. During MR07-04 in which we observed in the subarctic region, enough echo intensities for good observation (over 60 counts) were obtained up to bin number of 50. (4) Data processing We processed ADCP data as described below. ADCP-coordinate velocities were converted to the earth-coordinate velocities using the ship heading from the INU. The earth-coordinate currents were obtained by subtracting ship velocities from the earth-coordinate velocities. Corrections of the misalignment and scale factors were made using the bottom track data for each legs. The misalignment angle calculated was 0.5, 1, and 1 degree and the scale factor was 0.975 for MR07-04, MR07-06 leg1 and MR07-06 leg2, respectively. Fig. 2.5.1: Cruise-averaged echo intensities for each beams by bins. 2.6 XCTD 4 November 2008 (1) Personnel Hiroshi Uchida (JAMSTEC) Satoshi Okumura (GODI) Shinya Okumura (GODI) Ryo Ohyama (GODI) (2) Objectives Expendable Conductivity, Temperature and Depth profiler (XCTD) measurements were carried out to obtain upper ocean temperature and salinity data at CTD stations skipped over in the cruise MR07-04. (3) Instrument and Method The XCTD used was XCTD-1 (Tsurumi-Seiki Co., Ltd., Yokohama, Kanagawa, Japan) with a MK-100 deck unit (Tsurumi-Seiki Co., Ltd.). Ship's speed was slowed down to 12 knot during the XCTD measurement. In the cruise MR07-04, 17 XCTD-1 probes were deployed by using 8-loading automatic launcher (Tsurumi-Seiki Co., Ltd.), except for stations P01_42, 51, 53, 54, 55, 56, and 57 at which the XCTD probes were deployed by using hand launcher from the stern of the upper deck due to communication error. (4) Data Processing and Quality Control The XCTD data were processed and quality controlled based on a method by Uchida and Imawaki (2008) with slight modification. The followings are the data processing sequence used in the reduction of the XCTD data. 1. Raw temperature and conductivity data from the first nine scans of the XCTD data were deleted and data considerably deeper than depth range of the manufacturer's specifications and spikes were manually removed. 2. Missing data by the above editing was linearly interpolated when the data gap was within 15 scans (about 2 m). 3. Temperature and conductivity data were low-pass filtered (running mean with a window of 15 scans). 4. The conductivity data was advanced for 1.5 scans (about 0.2 m), instead of 2 scans described in Uchida and Imawaki (2008), relative to the temperature data to correct mismatch of response time of the sensors. 5. Pressure was estimated from depth and location (latitude) by calculating backward from a pressure to depth conversion equation (Saunders and Fofonoff, 1976), and salinity was calculated from the pressure, temperature and conductivity data by using the reference conductivity of 42.896 mS cm-1 at salinity of 35, temperature of 15°C (IPTS-68) and pressure of 0 dbar. The reference conductivity value is used in the manufacturer's data processing software. 6. The data were sampled at 1-dbar interval. 7. Salinity biases of the XCTD data were estimated by using tight relationship between temperature and salinity in the deep ocean. At in situ temperature of 2.75°C, mean salinity was 34.399 (SD, 0.006) and mean pressure was 993 dbar (SD, 53 dbar) for the CTD data obtained at four stations (P01_40, 44, 58, and 60). Difference between XCTD salinity and the mean CTD salinity at temperature of 2.75°C was considered to be salinity bias of the XCTD data (Table 2.6.1). For the XCTD data of the station P01_51, salinity bias could not be estimated because the maximum depth was too shallow to estimate the salinity bias. (5) Results Vertical sections of potential temperature and salinity are shown in Fig. 2.6.1 combining with CTD data obtained at four stations (P01_40, 44, 58, and 60). Relationship between potential temperature and salinity is also shown in Fig. 2.6.2. Table 2.6.1: Salinity offset correction value to the XCTD salinity data. Ship intake temperature (SST) and salinity (SSS), and maximum pressure for the XCTD data are also shown. ______________________________________________________ Max Salinity Serial SST SSS pressure offset Stn number [°C] [PSU] [dbar] [PSU] ------ -------- ------ ------ -------- -------- P01_41 03022140 10.725 32.974 1045 0.009 P01_42 02121625 10.580 32.857 1044 0.015 P01_43 02121627 10.048 32.835 1044 0.028 P01_45 03022141 9.656 32.801 1045 0.033 P01_46 03022142 9.676 32.858 1044 0.010 P01_47 03022176 9.892 32.858 1044 0.010 P01_48 03022171 9.988 32.840 1044 0.024 P01_49 03022174 10.116 32.794 1043 0.027 P01_50 03022172 10.074 32.782 1044 0.005 P01_51 03022170 10.000 32.798 484 - P01_52 03022149 10.100 32.739 1045 0.015 P01_53 03022148 10.293 32.755 1045 0.031 P01_54 03022146 10.774 32.756 1045 0.024 P01_55 03022152 10.788 32.719 1045 0.026 P01_56 03022147 10.858 32.735 1045 0.025 P01_57 03022151 11.579 32.797 1045 0.010 P01_59 03022144 11.560 32.770 1044 0.014 ______________________________________________________ Fig. 2.6.1: Vertical section of (a) potential temperature and (b) salinity. Filled triangles (open triangles) show station locations for the XCTD (CTD) measurements. Fig. 2.6.2: Potential temperature plotted against salinity for the XCTD (red curves) and CTD (blue curves) data obtained from station P01_40 to 60. (6) Data format Data format for the XCTD data is basically based on WOCE Exchange Format for the CTD data. Quality flags were set to "1" for the XCTD data except for the offset corrected salinity data for which quality flags were set to "2". Temperature and salinity profiles near the sea surface were filled with the shallowest values and the quality flags were set to "7". REFERENCES Saunders, P. M. and N. P. Fofonoff (1976): Conversion of pressure to depth in the ocean. Deep-Sea Res., 23, 109-111. Uchida, H. and S. Imawaki (2008): Estimation of the sea level trend south of Japan by combining satellite altimeter data with in situ hydrographic data. J. Geophys. Res., 113, C09035, doi:10.1029/2008JC004796. 3.1 CTD/O2 Measurements 11 December 2008 (1) Personnel Hiroshi Uchida (JAMSTEC) Satoshi Ozawa (MWJ) (MR07-04_1 and MR07-06_2) Hirokatsu Uno (MWJ) (MR07-04_1 and MR07-06_2) Tomoyuki Takamori (MWJ) (MR07-04_1 and MR07-06_2) Kenichi Katayama (MWJ) (MR07-04_1 and MR07-06_1) Hiroshi Matsunaga (MWJ) (MR07-06_1) Kentaro Ohyama (MWJ) (MR07-06_1) Shinsuke Toyoda (MWJ) (MR07-06_1) Tsutomu Fujii (MWJ) (MR07-06_2) (2) Winch arrangements The CTD package was deployed by using 4.5 Ton Traction Winch System (Dynacon, Inc., Bryan, Texas, USA), which was installed on the R/V Mirai in April 2001 (Fukasawa et al., 2004). Primary system components include a complete CTD Traction Winch System with up to 8000 m of 9.53 mm armored cable (Ocean Cable and Communications Co., Yokohama, Kanagawa, Japan). (3) Overview of the equipment The CTD system was SBE 911plus system (Sea-Bird Electronics, Inc., Bellevue, Washington, USA). The SBE 911plus system controls 36-position SBE 32 Carousel Water Sampler. The Carousel accepts 12-litre Niskin-X water sample bottles (General Oceanics, Inc., Miami, Florida, USA). The SBE 9plus was mounted horizontally in a 36-position carousel frame. SBE's temperature (SBE 3) and conductivity (SBE 4) sensor modules were used with the SBE 9plus underwater unit. The pressure sensor is mounted in the main housing of the underwater unit and is ported to outside through the oil-filled plastic capillary tube. A modular unit of underwater housing pump (SBE 5T) flushes water through sensor tubing at a constant rate independent of the CTD's motion, and pumping rate (3000 rpm) remain nearly constant over the entire input voltage range of 12-18 volts DC. Flow speed of pumped water in standard TC duct is about 2.4 m/s. Two sets of temperature and conductivity modules were used. An SBE's dissolved oxygen sensor (SBE 43) was placed between the primary conductivity sensor and the pump module. Auxiliary sensors, a Deep Ocean Standards Thermometer (SBE 35), an altimeter (PSA-916T; Teledyne Benthos, Inc., North Falmous, Massachusetts, USA), an oxygen optode (Oxygen Optode 3830; Aanderaa Data Instruments AS, Bergen, Norway), and a fluorometer (Seapoint sensors, Inc., Kingston, New Hampshire, USA) were also used with the SBE 9plus underwater unit. In addition, two prototypes of oxygen optode (RINKO; Alec Electronics Co. Ltd., Kobe, Hyogo, Japan) were also used. To minimize motion of the CTD package, a heavy stainless frame (total weight of the CTD package without sea water in the bottles is about 1000 kg) was used with an aluminum plate (54 • 90 cm: see Fig. 3.1.1 in Kawano and Uchida, 2007). Summary of the system used in the cruises MR07-04 and MR07-06 Deck unit: SBE 11plus, S/N 0272 Under water unit: SBE 9plus, S/N 79492 (Pressure sensor: S/N 0575) Temperature sensor: Primary SBE 3plus, S/N 4216 (stations from P01_1_1 to P01_44_1) SBE 3plus, S/N 4188 (stations from P01_58_1 to P01_115_1) (stations from P01_28_2 to P14N_4_1) SBE 3, S/N 1525 (stations from P14N_30_1 to P14C_1_1) Secondary SBE 3, S/N 1464 (stations from P01_1_1 to P01_29_1) SBE 3, S/N 1525 (stations from P01_40_1 to P01_115_1) (stations from P01_28_2 to P14N_4_1) SBE 3plus, S/N 4421 (stations from P14N_30_1 to P14N_33_1) SBE 3plus, S/N 4188 (stations from P14N_34_1 to P14N_73_1) SBE 3plus, S/N 4216 (stations from P14N_75_1 to P14C_1_1) * without secondary temperature sensor for station P14N_74_2 Conductivity sensor: Primary SBE 4, S/N 1203 (stations from P01_1_1 to P01_10_1) SBE 4, S/N 3064 (stations from P01_11_1 to P01_115_1) (stations from P01_28_2 to P14N_74_1) SBE 4, S/N 1206 (stations from P14N_74_2 to P14N_99_1) SBE 4, S/N 3116 (stations from P14N_100_1 to P14N_109_1) SBE 4, S/N 3124 (stations from P14N_109_2 to P14C_1_1) Secondary SBE 4, S/N 2854 (stations from P01_1_1 to P01_115_1) SBE 4, S/N 2240 (stations from P01_28_2 to P01_46_1) SBE 4, S/N 3036 (stations from P01_47_1 to P14N_51_1) SBE 4, S/N 2854 (stations from P14N_52_1 to P14N_74_1) SBE 4, S/N 2435 (stations from P14N_80_1 to P14N_171_1) SBE 4, S/N 1172 (stations from P14N_172_1 to P14C_1_1) * without secondary conductivity sensor for stations from P14N_74_2 to P14N_79_1 Oxygen sensor: SBE 43, S/N 0949 (stations from P01_1_1 to P01_115_1) SBE 43, S/N 0394 (stations from P01_28_2 to P14C_1_1) AANDERAA Oxygen Optode 3830, S/N 612 ALEC Oxygen Optode (RINKO, prototype I) (stations from P01_1_1 to P01_115_1) (stations from P01_28_2 to P14N_182_1) ALEC Oxygen Optode (RINKO, prototype II) (stations from P14N_109_2 to P14C_1_1) Pump: Primary SBE 5T, S/N 4598 (stations P01_1_1 to P01_58_2) SBE 5T, S/N 4595 (stations P01_60_1 to P01_115_1) (stations P01_28_2 to P14C_1_1) Secondary SBE 5T, S/N 4595 (stations P01_1_1 to P01_58_2) SBE 5T, S/N 4598 (stations P01_60_1 to P01_115_1) (stations P01_28_2 to P14C_1_1) Altimeter: PSA-916T, S/N 1157 Deep Ocean Standards Thermometer: SBE 35, S/N 0045 Fluorometer: Seapoint Sensors, Inc., S/N 2579 * without fluorometer for the following stations, because the maximum pressure was beyond the pressure-proof stations from P01_9_1 to P01_12_1, from P01_44_2 to P01_46_1, from P01_53_1 to P01_54_1, from P14N_24_1 to P14N_23_1, from P14N_100_1 to P14N_101_1, S/N 0575, 5 July 2007 from P14N_107_1 to P14N_109_2, slope = 0.99980507 and P14N_123_1 offset = 2.33363 Carousel Water Sampler: SBE 32, S/N 0391 Water sample bottle: 12-litre Niskin-X (no TEFLON coating) (4) Pre-cruise calibration i. Pressure The Paroscientific series 4000 Digiquartz high pressure transducer (Model 415K- 187: Paroscientific, Inc., Redmond, Washington, USA) uses a quartz crystal resonator whose frequency of oscillation varies with pressure induced stress with 0.01 per million of resolution over the absolute pressure range of 0 to 15000 psia (0 to 10332 dbar). Also, a quartz crystal temperature signal is used to compensate for a wide range of temperature changes at the time of an observation. The pressure sensor has a nominal accuracy of 0.015% FS (1.5 dbar), typical stability of 0.0015% FS/month (0.15 dbar/month), and resolution of 0.001% FS (0.1 dbar). Since the pressure sensor measures the absolute value, it inherently includes atmospheric pressure (about 14.7 psi). SEASOFT subtracts 14.7 psi from computed pressure automatically. Pre-cruise sensor calibrations for linearization were performed at SBE, Inc. S/N 0575, 27 October 1999 The time drift of the pressure sensor is adjusted by periodic recertification corrections against a dead-weight piston gauge (Model 480DA, S/N 23906; Bundenberg Gauge Co. Ltd., Irlam, Manchester, UK). The corrections are performed at JAMSTEC, Yokosuka, Kanagawa, Japan by Marine Works Japan Ltd. (MWJ), Yokohama, Kanagawa, Japan, usually once in a year in order to monitor sensor time drift and linearity. Result of the pre-cruise pressure sensor calibration against the dead-weight piston gauge is shown in Fig. 3.1.1. Figure 3.1.1: Difference between the dead-weight piston gauge and the CTD pressure. The calibration line (black line) is also shown. ii. Temperature (SBE 3) The temperature sensing element is a glass-coated thermistor bead in a stainless steel tube, providing a pressure-free measurement at depths up to 10500 (6800) m by titanium (aluminum) housing. The SBE 3 thermometer has a nominal accuracy of 1 mK, typical stability of 0.2 mK/month, and resolution of 0.2 mK at 24 samples per second. The premium temperature sensor, SBE 3plus, is a more rigorously tested and calibrated version of standard temperature sensor (SBE 3). Pre-cruise sensor calibrations were performed at SBE, Inc. S/N 4188, 16 May 2007 S/N 4216, 16 May 2007 S/N 1464, 28 June 2007 S/N 1525, 14 June 2007 S/N 4421, 14 June 2007 Pressure sensitivity of SBE 3 was corrected in accordance with a method by Uchida et al. (2007), for the following sensor. S/N 4188, -2.946675e-7 [°C/dbar] Time drift of the SBE 3 temperature sensors based on the laboratory calibrations is shown in Fig. 3.1.2. Figure 3.1.2: Time drift of SBE 3 temperature sensors based on laboratory calibrations. iii. Conductivity (SBE 4) The flow-through conductivity sensing element is a glass tube (cell) with three platinum electrodes to provide in-situ measurements at depths up to 10500 (6800) m by titanium (aluminum) housing. The SBE 4 has a nominal accuracy of 0.0003 S/m, typical stability of 0.0003 S/m/month, and resolution of 0.00004 S/m at 24 samples per second. Pre-cruise sensor calibrations were performed at SBE, Inc. S/N 1203, 14 June 2007 S/N 3064, 14 June 2007 S/N 1088, 14 June 2007 S/N 2240, 10 August 2007 S/N 3036, 10 May 2007 S/N 2854, 10 August 2007 S/N 1206, 10 May 2007 S/N 2435, 10 August 2007 S/N 3116, 16 May 2007 S/N 3124, 16 May 2007 S/N 1172, 14 June 2007 The value of conductivity at salinity of 35, temperature of 15°C (IPTS-68) and pressure of 0 dbar is 4.2914 S/m. iv. Oxygen (SBE 43) The SBE 43 oxygen sensor uses a Clark polarographic element to provide in-situ measurements at depths up to 7000 m. The range for dissolved oxygen is 120% of surface saturation in all natural waters, nominal accuracy is 2% of saturation, and typical stability is 2% per 1000 hours. Pre-cruise sensor calibrations were performed at SBE, Inc. S/N 0949, 1 June 2007 S/N 0394, 23 June 2007 v. Deep Ocean Standards Thermometer Deep Ocean Standards Thermometer (SBE 35) is an accurate, ocean-range temperature sensor that can be standardized against Triple Point of Water and Gallium Melt Point cells and is also capable of measuring temperature in the ocean to depths of 6800 m. The SBE 35 was used to calibrate the SBE 3 temperature sensors in situ (Uchida et al., 2007). Pre-cruise sensor linearization was performed at SBE, Inc. S/N 0045, 27 October 2002 Then the SBE 35 is certified by measurements in thermodynamic fixed-point cells of the TPW (0.0100°C) and GaMP (29.7646°C). The slow time drift of the SBE 35 is adjusted by periodic recertification corrections. Pre-cruise sensor calibration was performed at SBE, Inc. S/N 0045, 29 May 2007 (slope and offset correction) The time required per sample = 1.1 x NCYCLES + 2.7 seconds. The 1.1 seconds is total time per an acquisition cycle. NCYCLES is the number of acquisition cycles per sample and was set to 4. The 2.7 seconds is required for converting the measured values to temperature and storing average in EEPROM. When using the SBE 911 system with SBE 35, the deck unit receives incorrect signal from the under water unit for confirmation of firing bottle #16. In order to correct the signal, a module (Yoshi Ver. 1; EMS Co. Ltd., Kobe, Hyogo, Japan) was used between the under water unit and the deck unit. Time drift of the SBE 35 based on the fixed point calibrations is shown in Fig. 3.1.3. Figure 3.1.3: SBE35 time drift based on laboratory fixed point calibrations (triple point of water, TPW and gallium melt point, GaMP) performed by SBE, Inc. vi. Altimeter Benthos PSA-916T Sonar Altimeter (Teledyne Benthos, Inc.) determines the distance of the target from the unit by generating a narrow beam acoustic pulse and measuring the travel time for the pulse to bounce back from the target surface. It is rated for operation in water depths up to 10000 m. The PSA-916T uses the nominal speed of sound of 1500 m/s. vii. Oxygen Optode Oxygen Optode 3830 (Aanderaa Instruments AS) is based on the ability of selected substances to act as dynamic fluorescence quenchers. In order to use with the SBE 911plus CTD system, an analog adaptor (3966) is connected to the oxygen optode (3830). The analog adaptor is packed into titanium housing made by Alec Electronics Co. Ltd., Kobe, Hyogo, Japan. The sensor is designed to operate down to 6000 m. The range for dissolved oxygen is 120% of surface saturation in all natural waters, nominal accuracy is less than 5% of saturation, and setting time (68%) is shorter than 25 seconds. Outputs from the sensor are the raw phase shift and temperature. The optode oxygen can be calibrated in accordance with a method by Uchida et al. (2008) by using oxygen data obtained from discrete water samples. viii. Fluorometer The Seapoint Chlorophyll Fluorometer (Seapoint Sensors, Inc., Kingston, New Hampshire, USA) provides in-situ measurements of chlorophyll-a at depths up to 6000 m. The instrument uses modulated blue LED lamps and a blue excitation filter to excite chlorophyll-a. The fluorescent light emitted by the chlorophyll-a passes through a red emission filter and is detected by a silicon photodiode. The low level signal is then processed using synchronous demodulation circuitry, which generates an output voltage proportional to chlorophyll-a concentration. ix. Prototype of oxygen optode The prototype of oxygen optodes (RINKO prototype I and II: Alec Electronics Co. Ltd.) provides the raw phase shift and temperature at depths up to 7000 m. Pre- cruise calibration was not performed for the prototype sensors. The RINKO can also be calibrated in accordance with a method by Uchida et al. (2008) by using oxygen data obtained from discrete water samples. (5) Data collection and processing i. Data collection CTD system was powered on at least 20 minutes in advance of the data acquisition and was powered off at least two minutes after the operation in order to acquire pressure data on the ship's deck. The package was lowered into the water from the starboard side and held 10 m beneath the surface for about one minute in order to activate the pump. After the pump was activated, the package was lifted to the surface and lowered at a rate of 1.0 m/s to 200 m (or 300 m when significant wave height is high) then the package was stopped to operate the heave compensator of the crane. The package was lowered again at a rate of 1.2 m/s to the bottom. For the up cast, the package was lifted at a rate of 1.1 m/s except for bottle firing stops. At each bottle firing stops, the bottle was fired after waiting from the stop for 30 seconds and the package was stayed at least 5 seconds for measurement of the SBE 35. At 200 m (or 300 m) from the surface, the package was stopped to stop the heave compensator of the crane. Water samples were collected using a 36-bottle SBE 32 Carousel Water Sampler with 12-litre Niskin-X bottles. Before a cast taken water for CFCs, the 36- bottle frame and Niskin-X bottles were wiped with acetone. Data acquisition software SEASAVE-Win32, version 5.27b ii. Data collection problems Temperature sensor Scattering of difference between the primary temperature sensor S/N 4216 and the SBE 35 was slightly greater than that between the secondary temperature sensor S/N 1464 and the SBE 35. Therefore the temperature sensor S/N 4188 was used as primary temperature sensor after the station P01_44_1. Scattering of difference between the primary temperature sensor S/N 4188 and the SBE 35 was slightly greater than that between the secondary temperature sensor S/N 1525 and the SBE 35. Therefore the temperature sensor S/N 1525 was used as primary temperature sensor and the temperature sensor S/N 4421 was used as secondary temperature sensor after the station P14N_4_1. The secondary temperature sensor S/N 4421, however, showed large discrepancy (about 0.5 mK) between the down-cast and up-cast. Therefore the secondary temperature sensor was replaced with the temperature sensor S/N 4188 after the station P14N_33_1. Scattering of difference between the secondary temperature sensor S/N 4188 and the SBE 35 was gradually became large. Therefore the secondary temperature sensor S/N 4188 was replaced with the temperature sensor S/N 4216 after the station P14N_73_1. At the stations from P14N_75_1 to P14N_79_1, the secondary temperature sensor was used without the secondary conductivity sensor. The temperature sensor was directly connected with the pump by a tube. Consequently, the temperature sensor reading was about 1 mK higher than usual for the stations from P14N_75_1 to P14N_79_1. Conductivity sensor The conductivity sensor reading from the primary conductivity sensor was shifted during the down cast of station P01_7_1, P01_8_1, P01_9_1, and P01_10_1. Therefore the conductivity sensor was replaced after the station P01_10_1. The secondary conductivity sensor S/N 2240 was broken near the bottom of the station P01_45_1. Therefore the secondary conductivity sensor was replaced with the conductivity sensor S/N 3036 after the station P01_46_1. The secondary conductivity sensor S/N 3036 was broken near the bottom of the station P14N_51_1. Therefore the secondary conductivity sensor was replaced with the conductivity sensor S/N 2854 after the station. The primary and secondary conductivity sensors S/N 3064 and S/N 2854 were broken near the bottom of the station P14N_74_1. Therefore the primary conductivity sensor was replaced with the conductivity sensor S/N 1206 and the secondary temperature and conductivity sensors were removed from the CTD system after the station, and at the station P14N_80_1, the secondary conductivity sensor S/N 2435 was attached to the CTD system. The primary conductivity sensor S/N 3116 was broken near the bottom of the station P14N_108_1. Because the secondary conductivity sensor was in normal condition and the remaining station was only one station for the cruise MR07- 06_1, the broken conductivity sensor was left for the station P14N_109_1. At the beginning of the cruise MR07-06_2, the primary conductivity was replaced with the conductivity sensor S/N 3124. The secondary conductivity sensor S/N 2435 was broken near the bottom of the station P14N_171_1. Therefore the secondary conductivity sensor was replaced with the conductivity sensor S/N 1172 after the station. Because the conductivity sensor reading from the primary conductivity sensor S/N 1206 was slightly shifted during a long stop due to the winch trouble during the station P14N_98_1, the primary conductivity sensor was replaced with the conductivity sensor S/N 3116 after the station P14N_99_1. Prototype of oxygen optode At the station P14N_181_1, the sensor reading from RINKO prototype I was unstable during the down-cast, although the sensor reading was normal during the up-cast. At the station P14N_182_1, RINKO prototype I did not work during the cast due to leakage. Therefore the sensor was removed after the cast. Winch troubles At the station P01_34_1, a sensor in the hydraulic actuator of the crane broke at about 864 dbar of the up-cast. Therefore CTD was operated without heave motion of the crane at the station P01_35_1. At the station P14N_98_1, a chain rotating the cable drum broke at about 713 dbar of the down-cast and the CTD package was stopped at the depth for about 110 minutes during repair. At the station P14N_178_1, the CTD package rapidly approached the bottom before firing the bottle #1, and the neatly arranged cable on the winch drum broke down in disorder because the CTD package was quickly upped near the bottom. Therefore the cast was quitted. The station location was changed about one mile from the original location and the second cast was carried out. Miss trip and miss fire Niskin bottles did not trip correctly at the following stations. Miss trip Miss fire ---------------------- -------------- P01_23_1, #15 P14N_60_1, #26 P01_40_2, #10 P14N_71_1, #31 P01_54_1, #10 P14C_35_1, #11 P14N_54_1, #11 P14N_63_1, #11 P14N_64_1, #11 P14N_77_1, #27 P14N_92_1, #24 P14N_99_1, #18 P14N_101_1, #16 P14N_103_1, #5 P14N_107_1, #3 and #12 P14N_110_1, #2 P14N_126_1, #30 P14N_127_1, #28 P14C_50_1, #24 P14C_7_1, #22 Other incidents of note At station P01_29_1, a longline for fishery was caught in a propeller at about 5000 dbar of the down cast. Therefore the cast was quitted and no water was sampled. At station P01_58_1, primary temperature signal was lost at 2400 dbar of the down cast. Therefore the cast was quitted and the connection cable was replaced. At stations P01_81_1, P01_105_1 and P01_111_1, Jellyfish was in secondary T-C duct, and data quality from the secondary temperature and conductivity sensors was bad. The secondary T-C duct was cleaned with Triton-X after the casts. At station P01_115_1, a fishing boat existed near the planned location. Therefore the station location was changed a little to the north. At the station P01_47_1, the secondary temperature and conductivity data were noisy. At the station P14N_55_1, the SBE 35 data of bottle #8 was lost, because the next bottle firing command was sent before storing the SBE 35 data in the internal memory. At the station P14N_140_1, the secondary salinity data did not change from zero. Therefore the cast was quitted. The secondary sensors were flushed with water and the second cast was carried out. iii. Data processing SEASOFT consists of modular menu driven routines for acquisition, display, processing, and archiving of oceanographic data acquired with SBE equipment. Raw data are acquired from instruments and are stored as unmodified data. The conversion module DATCNV uses instrument configuration and calibration coefficients to create a converted engineering unit data file that is operated on by all SEASOFT post processing modules. The following are the SEASOFT and original software data processing module sequence and specifications used in the reduction of CTD data in this cruise. Data processing software SEASOFT-Win32, version 5.27b DATCNV converted the raw data to engineering unit data. DATCNV also extracted bottle information where scans were marked with the bottle confirm bit during acquisition. The duration was set to 4.4 seconds, and the offset was set to 0.0 second. TCORP (original module, version 1.0) corrected the pressure sensitivity of the SBE 3 for both profile and bottle information data. One SBE 3 (S/N 4188) was corrected because it had relatively large pressure sensitivity (about +1.8 mK per 6000 dbar). ROSSUM created a summary of the bottle data. The data were averaged over 4.4 seconds. ALIGNCTD converted the time-sequence of sensor outputs into the pressure sequence to ensure that all calculations were made using measurements from the same parcel of water. For a SBE 9plus CTD with the ducted temperature and conductivity sensors and a 3000-rpm pump, the typical net advance of the conductivity relative to the temperature is 0.073 seconds. So, the SBE 11plus deck unit was set to advance the primary and the secondary conductivity for 1.73 scans (1.75/24 = 0.073 seconds). Oxygen data are also systematically delayed with respect to depth mainly because of the long time constant of the oxygen sensor and of an additional delay from the transit time of water in the pumped plumbing line. This delay was compensated by 6 seconds advancing oxygen sensor output (oxygen voltage) relative to the temperature data. Data from the RINKO prototype I and II were also delayed 2 seconds relative to the temperature data. ALIGNOPT (original module, version 0.1) also compensated the delay of the AANDERAA optode sensor by advancing relative to the CTD temperature data as a function of temperature (t). align (sec) = 25 x exp(-0.13 x t) (for 0 ≤ t ≤ 16.3°C) = 25 (fort < 0°C) = 3 (fort > 16.3°C) WILDEDIT marked extreme outliers in the data files. The first pass of WILDEDIT obtained an accurate estimate of the true standard deviation of the data. The data were read in blocks of 1000 scans. Data greater than 10 standard deviations were flagged. The second pass computed a standard deviation over the same 1000 scans excluding the flagged values. Values greater than 20 standard deviations were marked bad. This process was applied to all variables. CELLTM used a recursive filter to remove conductivity cell thermal mass effects from the measured conductivity. Typical values used were thermal anomaly amplitude alpha = 0.03 and the time constant 1/beta = 7.0. FILTER performed a low pass filter on pressure with a time constant of 0.15 seconds. In order to produce zero phase lag (no time shift) the filter runs forward first then backwards. WFILTER performed as a median filter to remove spikes in fluorometer data. A median value was determined by 49 scans of the window. SECTION (or original module of SECTIONU, version 1.0) selected a time span of data based on scan number in order to reduce a file size. The minimum number was set to be the start time when the CTD package was beneath the sea-surface after activation of the pump. The maximum number was set to be the end time when the package came up from the surface. Data for estimation of the CTD pressure drift were prepared before SECTION. LOOPEDIT marked scans where the CTD was moving less than the minimum velocity of 0.0 m/s (traveling backwards due to ship roll). DESPIKE (original module, version 1.0) removed spikes of the data. A median and mean absolute deviation was calculated in 1-dbar pressure bins for both down- and up-cast, excluding the flagged values. Values greater than 4 mean absolute deviations from the median were marked bad for each bin. This process was performed 2 times for temperature, conductivity, oxygen voltage (SBE 43) and optode oxygen (AANDERAA) data. DERIVE was used to compute oxygen (SBE 43). BINAVG averaged the data into 1-dbar pressure bins. The center value of the first bin was set equal to the bin size. The bin minimum and maximum values are the center value plus and minus half the bin size. Scans with pressures greater than the minimum and less than or equal to the maximum were averaged. Scans were interpolated so that a data record exist every dbar. DERIVE was re-used to compute salinity, potential temperature, and density (__). SPLIT was used to split data into the down cast and the up cast. The shift of the primary conductivity data at stations P01_7_1, P01_8_1, P01_9_1, and P01_10_1 were corrected by using original module SHIFTCORR. The conductivity sensor gradually shifted from 1000 dbar to the following depth of the down cast. Magnitude of the shift at the following depth was estimated and the conductivity data between 1000 dbar and the following depth was linearly corrected. Maximum depth Magnitude of the shift Station of the shift at the maximum depth -------- ------------- ---------------------- P01_7_1 4170 dbar -0.00003 S/m P01_8_1 3774 dbar -0.00001 S/m P01_9_1 5850 dbar -0.00002 S/m P01_10_1 5820 dbar -0.00004 S/m For the station P14N_36_1, bad quality data of the primary temperature and conductivity between 37 and 78 dbar of the down-cast were corrected by using original module SWAP. The bad quality data were replaced with the secondary temperature and conductivity data for the depths. Offsets of the secondary temperature and conductivity data relative to the primary temperature and conductivity data at the depths were estimated from the upper and lower data and were subtracted from the secondary data. For the station P14N_36_1, bad quality data of the SBE43 between the surface and 70 dbar of the down-cast were replaced by the up-cast data of the SBE43. Remaining spikes in temperature and salinity data were manually eliminated from the 1-dbar-averaged data. The following data gaps over 1-dbar were linearly interpolated with a quality flag of 6. Station Pressure (dbar) Parameters ---------- ----------------------- ---------- P01_2_1 348 Salinity P01_4_1 70 Salinity P01_5_1 413, 435-440, 456, 475, Salinity 485, 485, 503-504 P01_12_1 173 Salinity P01_21_1 826 Salinity P01_25_1 108, 416 Salinity P01_70_1 202, 207 Salinity P01_72_1 384 Salinity P01_X15_1 480 Salinity P01_79_1 141 Salinity P01_82_1 1776-1780 Salinity P01_84_1 26 Temperature, Salinity P01_114_1 284-290 Salinity P01_115_1 20 Salinity P01_28_2 99 Salinity P01_33_1 480 Salinity P01_57_1 73 Salinity P14N_110_1 300 Temperature P14N_111_1 139, 199 Temperature P14N_154_1 201 Temperature P14N_164_1 627 Salinity P14N_170_1 1387 Salinity P14C_10_1 50 Temperature P14C_10_1 49-50 Salinity P14C_6_1 1520 Salinity (6) Post-cruise calibration i. Pressure The CTD pressure sensor offset in the period of the cruise was estimated from the pressure readings on the ship deck. For best results the Paroscientific sensor was powered on for at least 20 minutes before the operation. In order to get the calibration data for the pre- and post-cast pressure sensor drift, the CTD deck pressure was averaged over first and last one minute, respectively. Then the atmospheric pressure deviation from a standard atmospheric pressure (14.7 psi) was subtracted from the CTD deck pressure. The atmospheric pressure was measured at the captain deck (20 m high from the base line) and sub-sampled one-minute interval as a meteorological data. Time series of the CTD deck pressure is shown in Fig. 3.1.4. The CTD pressure sensor offset was estimated from the deck pressure obtained above. Mean of the pre-and the post-casts data over the whole period gave an estimation of the pressure sensor offset from the pre-cruise calibration. Mean residual pressure between the dead-weight piston gauge and the calibrated CTD data at 0 dbar of the pre-cruise calibration was subtracted from the mean deck pressure. Estimated mean offset of the pressure data is listed in Table 3.1.1. The post-cruise correction of the pressure data is not deemed necessary for the pressure sensor. Table 3.1.1 Offset of the pressure data. Mean and standard deviation are calculated from time series of the average of the pre- and the post-cast deck pressures. _______________________________________________________ Mean deck Standard Residual Estimated Cruise pressure deviation pressure offset --------- --------- --------- --------- --------- MR07-04_1 0.12 dbar 0.09 dbar 0.06 dbar 0.06 dbar MR07-06_1 0.11 dbar 0.09 dbar 0.06 dbar 0.05 dbar MR07-06_2 0.16 dbar 0.17 dbar 0.06 dbar 0.10 dbar _______________________________________________________ Figure 3.1.4: Time series of the CTD deck pressure. Pink dot indicates atmospheric pressure anomaly. Blue and green dots indicate pre- and post-cast deck pressures, respectively. Red dot indicates an average of the pre- and the post-cast deck pressures. ii. Temperature The CTD temperature sensors (SBE 3) were calibrated with the SBE 35 under the assumption that discrepancies between SBE 3 and SBE 35 data were due to pressure sensitivity, the viscous heating effect, and time drift of the SBE 3, in accordance with a method by Uchida et al. (2007). Post-cruise sensor calibration for the SBE 35 was performed at SBE, Inc. S/N 0045, 8 February 2008 (2nd step: fixed point calibration) Slope = 1.000014 Offset = -0.001127 Offset of the SBE 35 data from the pre-cruise calibration was estimated to be smaller than 0.2 mK for temperature smaller than 4.5°C. So the post-cruise correction of the SBE 35 temperature data was not deemed necessary for the SBE 35. The CTD temperature was calibrated as Calibrated temperature = T - (c0 x P + c1 x t + c2) where T is CTD temperature in°C, P is pressure in dbar, t is time in days from pre-cruise calibration date of CTD temperature and c0, c1, and c2 are calibration coefficients. The coefficients were determined using the data for the depths deeper than 1950 dbar. The primary temperature data were basically used for the post-cruise calibration. The secondary temperature sensor was also calibrated and used instead of the primary temperature data, because the primary conductivity data was not able to be used for the stations P14N_108_1 and P14N_109_1. The number of data used for the calibration and the mean absolute deviation from the SBE 35 are listed in Table 3.1.2 and the calibration coefficients are listed in Table 3.1.3. The results of the post-cruise calibration for the CTD temperature are summarized in Table 3.1.4 and shown in Figs. 3.1.5 ~ 3.1.7. Table 3.1.2: Number of data used for the calibration (pressure •• 1950 dbar) and mean absolute deviation between the CTD temperature and the SBE 35. Serial number 4216 for the cruise MR07-06_1 was secondary temperature sensor. __________________________________________________________________________ Mean Serial absolute Cruise number Number deviation Note --------- ------ ------ --------- ---------------------------------- MR07-04_1 4216 382 0.1 mK Stns. from P01_1_1 to P01_44_1 4188 760 0.1 mK Stns. from P01_58_1 to P01_115_1 MR07-06_1 4188 825 0.1 mK Stns. from P01_28_2 to P14N_4_1 1525 1210 0.1 mK Stns. from P14N_30_1 to P14N_109_1 4216 421 0.1 mK Stns. from P14N_80_1 to P14N_109_1 MR07-06_2 1525 1528 0.1 mK __________________________________________________________________________ Table 3.1.3: Calibration coefficients for the CTD temperature sensors. _____________________________________________________ Serial Cruise number c0(°C/dbar) c1(°C/day) c2(°C) --------- ------ ----------- ---------- ------ MR07-04_1 4216 2.02667e-8 -2.25241e-5 0.0027 4188 4.44381e-8 2.69275e-5 -0.0016 MR07-06_ 1 4188 3.85600e-8 1.54264e-5 -0.0013 1525 -6.56477e-9 1.76679e-5 -0.0018 4216 4.66846e-8 -6.65040e-5 -0.0129 MR07-06_2 1525 8.24860e-9 -1.23300e-5 0.0028 _____________________________________________________ Table 3.1.4: Difference between the CTD temperature and the SBE 35 after the post-cruise calibration. Mean and standard deviation (Sdev) are calculated for the data below and above 1950 dbar. Number of data used is also shown. ____________________________________________________________________ Pressure ≥ 1950 dbar Pressure < 1950 dbar -------------------------- -------------------------- Cruise Number Mean(mK) Sdev(mK) Number Mean(mK) Sdev(mK) --------- ------ -------- -------- ------ -------- -------- MR07-04_1 1142 0.00 0.1 1589 0.35 12.7 MR07-06_1 1570 0.00 0.2 2962 0.01 6.9 MR07-06_2 2121 0.00 0.1 3007 -0.15 8.4 ____________________________________________________________________ Figure 3.1.5: Difference between the CTD temperature and the SBE 35 for the cruise MR07-04_1. Blue/cyan and red/magenta dots indicate before and after the post-cruise calibration using the SBE 35 data, respectively. Top panel shows for P ≥ 1950 dbar. Lower two panels show histogram of the difference after the calibration. Figure 3.1.6: Same as Fig. 3.1.5, but for the cruise MR07-06_1. Figure 3.1.7: Same as Fig. 3.1.5, but for the cruise MR07-06_2. iii. Salinity The discrepancy between the CTD salinity and the bottle salinity is considered to be a function of conductivity and pressure. The CTD salinity was calibrated as Calibrated salinity = S - (c0 x P + c1 x C + c2 x C x P + c3) where S is CTD salinity, P is pressure in dbar, C is conductivity in S/m and c0, c1, c2 and c3 are calibration coefficients. The best fit sets of coefficients were determined by minimizing the sum of absolute deviation with a weight from the bottle salinity data. The MATLAB(r) function FMINSEARCH was used to determine the sets. The weight was given as a function of vertical salinity gradient and pressure as Weight = min[4, exp{log(4) x Gr/Grad}] x min[4, exp{log(4) x P2/PR2}] where Grad is vertical salinity gradient in PSU dbar-1, and P is pressure in dbar. Gr and PR are threshold of the salinity gradient (0.5 mPSU dbar-1) and pressure (1000 dbar), respectively. When salinity gradient is small (large) and pressure is large (small), the weight is large (small) at maximum (minimum) value of 16 (1). The salinity gradient was calculated using up cast CTD salinity data. The up cast CTD salinity data was low-pass filtered with a 3- point (weights are 1/4, 1/2, 1/4) triangle filter before the calculation. The primary conductivity data created by the software module ROSSUM were basically used after the post-cruise calibration for the temperature data. For the stations P14N_108_1 and P14N_109_1, the secondary conductivity data was used, because the primary conductivity data was not able to be used for the stations. The coefficients were determined for some groups of the CTD stations. The results of the post-cruise calibration for the CTD salinity are summarized in Table 3.1.5 and shown in Figs. 3.1.8 and 3.1.9. And the calibration coef- ficients and number of data used for the calibration are listed in Table 3.1.6. Table 3.1.5: Difference between the CTD salinity and the bottle salinity after the post-cruise calibration. Mean and standard deviation (Sdev) are calculated for the data below and above 950 dbar. Number of data used is also shown. ____________________________________________________________________ Pressure ≥ 950 dbar Pressure < 950 dbar -------------------------- -------------------------- Cruise Number Mean Sdev Number Mean Sdev --------- ------ -------- -------- ------ -------- -------- MR07-04_1 1494 0.0 0.4 1105 -5.7 19.1 MR07-06_1 2672 0.0 0.4 1870 0.0 4.3 MR07-06_2 2067 -0.1 0.5 1647 1.1 8.8 ____________________________________________________________________ Table 3.1.6: Calibration coefficients for the CTD salinity. Number of data used is also listed. _______________________________________________________________________________________ Station Number c0 c1 c2 c3 ------------ ------ --------------- --------------- --------------- ---------- MR07-04_1 P01_1-28 824 1.0331764015e-5 1.6322214271e-3 -3.1041705576e-6 -5.21792e-3 P01_40-82 845 5.5743728228e-6 -7.5153334807e-3 -1.5802276835e-6 2.33384e-2 P01_83-92 357 -2.6365673251e-6 -1.7948408615e-2 9.9643702860e-7 5.64183e-2 P01_X17-115 568 -6.8043279569e-7 -1.1413741305e-2 3.6019288465e-7 3.54391e-2 MR07-06_1 P01_28 33 1.2366877766e-5 -3.1864710265e-3 -3.7410180073e-6 8.30924e-3 P01_29 34 1.4429501944e-5 -1.7179786902e-3 -4.3563216655e-6 3.81095e-3 P01_30 33 8.0524469712e-6 -4.6347655243e-3 -2.3595978265e-6 1.29389e-2 P01_32-33 101 1.1753176804e-5 -2.5920297513e-3 -3.5208528038e-6 6.03307e-3 P01_34-41 261 5.2675994458e-6 -4.3909897182e-3 -1.5450824887e-6 1.17190e-2 P01_42-46 216 7.0309692113e-6 -4.3031061185e-3 -2.0723214458e-6 1.08889e-2 P01_47-57 341 1.1092775540e-5 -2.3272648509e-3 -3.3053060435e-6 3.57009e-3 P01_58-59 71 3.2310197116e-6 -4.4057460257e-3 -9.2624113598e-7 1.08304e-2 P01_60-4 826 6.7400531759e-6 -2.7670250955e-3 -1.9631840097e-6 4.12712e-3 P14N_30-39 356 6.2991911918e-6 -1.7666229796e-3 -1.8995982920e-6 1.75626e-3 P14N_40-53 477 5.0547425123e-6 -7.9209509292e-4 -1.5177307189e-6 -1.96119e-3 P14N_54-73 633 3.1759512104e-6 -1.0157437278e-3 -9.4764638711e-7 -1.42327e-3 P14N_74-77 34 2.4469862353e-6 6.4594035205e-4 -7.2598062391e-7 -8.86545e-4 P14N_78-81 133 4.7865965493e-6 1.6054792872e-4 -1.4517360658e-6 -1.54977e-4 P14N_82-99 545 4.3956514692e-7 1.0331301338e-4 -1.1130619565e-7 1.08226e-4 P14N_100-107 271 4.2884569782e-6 -1.7427574735e-3 -1.2594920500e-6 8.51481e-3 P14N_108-109 70 6.0865582513e-6 -4.5049125413e-4 -1.7802113940e-6 2.18567e-3 MR07-06_2 P14N_109-115 232 2.3777541759e-6 -1.3933958135e-3 -6.6273977628e-7 8.17648e-3 P14N_116-127 417 3.5670485696e-6 -1.1006125106e-3 -1.0346847842e-6 6.86221e-3 P14N_128-138 377 1.3987382078e-6 -1.4065398654e-3 -3.4347529939e-7 7.53518e-3 P14N_139-144 205 2.8354655464e-6 -1.2215836660e-3 -7.9541774815e-7 6.53515e-3 P14N_145-149 170 3.1542072660e-6 -2.0613822363e-3 -8.9077088694e-7 8.87180e-3 P14N_150-158 301 4.8230368910e-6 -1.2147005582e-3 -1.4092637192e-6 5.57979e-3 P14N_159-174 505 1.6174979975e-6 -1.1887433192e-3 -3.8999095831e-7 4.42873e-3 P14N_175- 1484 -1.2626975255e-6 -1.0905094466e-3 5.9573995339e-7 2.43615e-3 P14C_1 _______________________________________________________________________________________ Figure 3.1.8: Difference between the CTD salinity and the bottle salinity for the cruise MR07-04_1. Blue and red dots indicate before and after the post-cruise calibration using the bottle salinity data, respectively. Top panel shows for P ≥ 950 dbar. Lower two panels show histogram of the difference after the calibration. Figure 3.1.9: Same as Fig. 3.1.8, but for the cruise MR07-06_1. Figure 3.1.10 Same as Fig. 3.1.8, but for the cruise MR07-06_2. iv. Oxygen (MR07-04) The AANDERAA and ALEC oxygen optodes were calibrated for the cruise MR07-04. AANDERAA oxygen optode The AANDERAA oxygen optode was calibrated by the Stern-Volmer equation, according to a method by Uchida et al. (2008): O2 (µmol/l) = (P0/P - 1)/Ksv where P is the phase shift, P0 is the phase shift in the absence of oxygen and Ksv is Stern-Volmer constant. The P0 and the Ksv are assumed to be functions of temperature as follows. Ksv = C11 + C12 x t + C13 x t2 P0 = C21 + C22 x t P = C31 + C32 x Pb where t is CTD temperature (°C) and Pb is raw phase measurement (deg). The oxygen concentration was calculated using temperature data from the first responding CTD temperature sensor instead of temperature data from slow responding optode temperature sensor. The calibration was performed for the up cast phase data created by the software module ROSSUM after the post-cruise calibration for the CTD temperature and salinity. The calibration coefficients (C11, C12, C13, C21, C22, C31 and C32) were determined for all CTD stations. The offset (C31) for the phase shift was slightly changed for the 6 groups of CTD casts. The results of the post-cruise calibration for the optode oxygen are summarized in Table 3.1.7 and shown in Fig. 3.1.8. And the calibration coefficients and number of data used for the calibration are listed in Table 3.1.8. Although the up cast optode data was well calibrated in situ (Fig. 3.1.8), difference between the up and down cast was quite large in the surface layer (~150 dbar) (Fig. 3.1.9). Similar discrepancy was seen in the data obtained in the North Pacific subarctic region (MR06-03_2), and was not seen in the data obtained in the North Pacific subtropical region (MR05-05) (Uchida et al., 2008). Data quality of the in-situ calibrated down cast optode data was bad in the surface layer. The optode oxygen data from the down cast was about 1 µmol/kg smaller than that from the up cast at depths between 1000 and 3000 dbar (Uchida et al., 2008). Although more work needs to be done on understanding the sensor's response under various situations at ambient temperature and in a vertical gradient of oxygen for more accurate compensation for the profile data, the down cast profile data were empirically corrected by using following equation. O2c = O2 + 20 x dO2/dp where O2 is the optode oxygen (µmol/kg) and p is pressure (dbar). For the calculation of the derivative, the oxygen profile was low-pass filtered by using a box-car filter with a window of 5 dbar before the calculation. The results of the correction is shown in Fig. 3.1.10. Table 3.1.7 Difference between the optode oxygen and the bottle oxygen after the post-cruise calibration. Mean and standard deviation (Sdev) are calculated for the data below and above 950 dbar. Number of data used is also shown. ______________________________________________________________ Pressure ≥ 950 dbar Pressure < 950 dbar ---------------------------- ---------------------------- Mean Sdev Mean Sdev Number (µmol/kg) (µmol/kg) Number (µmol/kg) (µmol/kg) ------ --------- --------- ------ --------- --------- 1510 0.01 0.31 1118 0.10 2.00 ______________________________________________________________ Fig. 3.1.8: Difference between the optode oxygen and the bottle oxygen. Blue and red dots indicate before and after the post-cruise calibration using the bottle salinity data, respectively. Lower two panels show histogram of the difference after the calibration. Table 3.1.8: Calibration coefficients for the optode oxygen. Number of data used is also listed. __________________________________________________________________________ Mean absolute Number deviation Coefficients Group of CTD casts ------ --------------- --------------------------- ------------------ 2627 0.60 µmol/kg C11 = 2.635256348237611e-03 C12 = 1.225025719497667e-04 C13 = 1.761916331924197e-06 C21 = 60.17218865923306 C22 = 8.903986993195000e-02 C31 = -6.060184746615353 1_1 - 9_1 = -6.004547679479678 10_1 - 17_1 = -6.053733067496423 18_1 - 23_1 = -6.105901740541861 24_1 - 28_1 = -6.018089856760813 40_1 - 103_1 = -6.069381437495752 104_1 - 115_1 C32 = 1.090377252560871 __________________________________________________________________________ Fig. 3.1.9: Mean oxygen difference between the down and up casts (up-down) for the SBE 43 (green line), the oxygen optode (blue line) and the prototype oxygen optode (red line) obtained from the cruise MR07-04. Thin lines represent 1 standard deviation from the mean profile. Fig. 3.1.10: Mean oxygen difference between the down and up casts (down-up) for the oxygen optode before (closed circles) and after (open circles) the correction (see text for detail). ALEC prototype oxygen optode (RINKO) The prototype of ALEC oxygen optode was calibrated by the Stern-Volmer equation, according to a method by Uchida et al. (2008): O2 (µmol/l) = (P0/P-1)/Ksv where P is the phase shift, P0 is the phase shift in the absence of oxygen and Ksv is Stern-Volmer constant. The P0 and the Ksv are assumed to be functions of temperature as follows. Ksv = C11 + C12 x t + C13 x t2 P0 = C21 + C22 x t P = C31 + C32 x V where t is CTD temperature (°C) and V is raw sensor output (voltage). The response of the sensing foil of the prototype optode decreases with increasing ambient pressure, and this pressure effect was estimated to decrease the response by 2.8% per 1000 dbar. The oxygen concentration was calculated using temperature data from the first responding CTD temperature sensor instead of temperature data from slow responding optode temperature sensor. The calibration was performed for the up cast data created by the software module ROSSUM after the post-cruise calibration for the CTD temperature and salinity. The calibration coefficients (C11, C12, C13, C21, C22, C31 and C32) were determined for some groups of the CTD stations. The offset (C31) for the phase shift was slightly changed for each CTD cast. The calibration coefficients and number of data used for the calibration are listed in Table 3.1.9. The results of the post-cruise calibration are summarized in Table 3.1.10 and shown in Fig. 3.1.11. In the post-cruise calibration, data depths deeper than 2000 dbar were not used for the first 2 groups (Stns. 1~15 and 16~28) because the calibration coefficients were not well determined when the data were included. Therefore the quality flag of the calibrated oxygen data depths deeper than 2000 dbar were set to 3 for stations from 1 to 28. Although the up cast optode data was well calibrated in situ (Fig. 3.1.11) and performance in the surface layer was quite well (Fig. 3.1.9), difference between the up and down cast was quite large in the deep layer (depths deeper than 1500 dbar). Fig. 3.1.11: Difference between the prototype optode oxygen and the bottle oxygen for after the post-cruise calibration. Top panel shows for P ≥ 950 dbar. Lower two panels show histogram of the difference. Table 3.1.9: Calibration coefficients for the prototype of oxygen optode. Number of data (Num) used and mean absolute deviation (Adev) are also listed. ___________________________________________________________________________________________________ Stn Num Adev Cll Cl2 013 C2l C22 C32 ------- --- ---- ------------ ------------ ------------ --------- ------------- --------- 1-15 246 1.19 5.8789102e-3 1.3202160e-4 -1.4972252e-6 6.7651313 -8.4590827e-2 1.6812784 16-28 239 1.47 6.050691ge-3 6.2425650e-5 -4.7143030e-7 8.1756988 -1.3633868e-1 2.0311299 40-68 375 0.70 5.3269802e-3 3.1786415e-4 -3.9858532e-6 6.028851S -2.S233800e-2 1.6248560 69-78 343 0.41 5.1852402e-3 2.5808996e-4 6.0745581e-7 5.7606052 -1.3581176e-2 1.5629738 79-87 336 0.36 5.1906670e-3 2.627341ge-4 5.0734085e-7 5.6164948 -1.1385041e-2 1.5362879 88-97 317 0.54 5.1486342e-3 2.3234328e-4 2.691052ge-7 6.3327141 -2.0598345e-2 1.7236231 98-104 198 0.43 5.2445225e-3 1.9401424e-4 1.4324301e-6 6.0844733 -2.9092447e-2 1.6510633 105-115 221 1.05 5.1940610e-3 2.2635952e-4 1.0836666e-6 7.3620419 -1.6032098e-2 2.0102865 Stn C31 Stn C31 Stn C31 Stn C31 --- --------- --- ---------- --- ---------- --- ---------- 1 -1.4663410 16 -1.8044790 40 -1.5211045 69 -1.4133193 2 -1.5028371 17 -1.8013574 44 -1.5283612 70 -1.4127655 3 -1.4959721 18 -1.7933317 58 -1.5244686 71 -1.4092531 4 -1.4995386 19 -1.7848185 60 -1.5257361 72 -1.4092409 5 -1.4968510 20 -1.7851197 61 -1.5231930 73 -1.4070984 6 -1.5046124 21 -1.7818728 62 -1.5239379 74 -1.1079670 7 -1.4828724 22 -1.7922501 63 -1.5199569 X15 -1.4055382 8 -1.4845656 23 -1.7746797 64 -1.5214495 76 -1.4020200 9 -1.4752667 24 -1.7617735 65 -1.5190013 77 -1.4060858 10 -1.4907149 25 -1.7543922 66 -1.5220141 78 -1.4020048 11 -1.4728418 26 -1.7486554 67 -1.5200137 12 -1.4852094 27 -1.7497571 68 -1.5197691 13 -1.4586884 28 -1.7557400 14 -1.4565111 15 -1.4541353 Stn C31 Stn C31 Stn C31 Stn C31 --- ---------- --- ---------- --- ---------- --- ---------- 79 -1.4005308 88 -1.5249214 98 -1.4498959 l05 -1.7497139 80 -1.4002417 89 -1.5217801 99 -1.4473812 106 -1.7414551 81 -1.3991096 90 -1.5212776 100 -1.4476825 107 -1.7506227 82 -1.3983053 91 -1.5184959 101 -1.4488230 108 -1.7414919 83 -1.3970340 92 -1.5172182 102 -1.4451071 109 -1.7450724 84 -1.3965286 Xl7 -1.5150712 103 -1.4435156 110 -1.7421465 85 -1.3945384 94 -1.5141203 104 -1.4391912 111 -1.733B304 86 -1.3943334 95 -1.5103182 112 -1.7424335 X16 -1.3928051 96 -1.5127131 l13 -1.7349491 87 -1.3923077 97 -1.5110558 114 -1.7298328 115 -1.7540911 ___________________________________________________________________________________________________ Table 3.1.10: Difference between the prototype optode oxygen and the bottle oxygen after the post-cruise calibration. Mean and standard deviation (Sdev) are calculated for the data below and above 950 dbar. Number of data used is also shown. ______________________________________________________________ Pressure ≥ 950 dbar Pressure < 950 dbar ---------------------------- ---------------------------- Mean Sdev Mean Sdev Number (µmol/kg) (µmol/kg) Number (µmol/kg) (µmol/kg) ------ --------- --------- ------ --------- --------- 1158 0.03 0.24 1118 0.15 2.59 ______________________________________________________________ Combined use of the two optode oxygen data Final CTD oxygen data were produced by combining the two optode oxygen data, because the data quality of the down cast data for the AANDERAA oxygen optode was bad in the surface layer and for the ALEC prototype oxygen optode was bad in the deep layer. The combined oxygen O in µmol/kg was calculated as follows: O = O1 (forP ≤ 800 dbar) = O2 (for P ≥ 1000 dbar) = W1 x O1 + W2 x O2 (for 800 dbar < P < 1000 dbar) W1 = (1000 - P)/(1000 - 800) W2 = 1 - W1 where O1 is the ALEC prototype optode oxygen in µmol/kg, O2 is the AANDERAA optode oxygen in µmol/kg, and P is pressure. The comparisons between the combined optode oxygen and the bottle oxygen are summarized in Table 3.1.11. Table 3.1.11 Difference between the combined optode oxygen and the bottle oxygen after the post-cruise calibration. Mean and standard deviation (Sdev) are calculated for the data below and above 950 dbar. Number of data used is also shown. ______________________________________________________________ Pressure ≥ 950 dbar Pressure < 950 dbar ---------------------------- ---------------------------- Mean Sdev Mean Sdev Number (µmol/kg) (µmol/kg) Number (µmol/kg) (µmol/kg) ------ --------- --------- ------ --------- --------- 1510 0.01 0.31 1118 0.15 2.59 ______________________________________________________________ v. Oxygen (MR07-06) The SBE 43 oxygen sensor was calibrated for the cruise MR07-06 as follows. O2 [ml/l] = Soc x {v+offset} x exp{(TCor) x t + (PCor) x p} x Oxsat(t, s) where p is pressure in dbar, t is temperature in °C and s is salinity in psu. Oxsat is oxygen saturation value minus the volume of oxygen gas (STP) absorbed from humidity-saturated air. Soc, offset, TCor and PCor are the calibration coefficients. The best fit sets of coefficients are determined by minimizing the sum of absolute deviation with a weight from the bottle oxygen data. The down-cast CTD data sampled at same density of the up-cast CTD data created by the software module ROSSUM are used after the post-cruise calibration for the CTD temperature and salinity. The coefficients were determined for some groups of the CTD stations. The calibration coefficients and number of the data used for the calibration are listed in Table 3.1.12. The results of the post-cruise calibration for the CTD oxygen are summarized in Table 3.1.13 and shown in from Figures 3.1.12 and 3.1.13. Table 3.1.12: Calibration coefficients for the CTD oxygen. Number of data used is also listed. _________________________________________________________________________________ Station Num Soc Offset Tcor PCor ---------------------- --- --------- ---------- ------------ ------------ P01_28_2-P01_36_1 299 0.4617342 -0.5212380 2.2118097e-3 1.3725459e-4 P01_37_1-P01_44_2 313 0.4654003 -0.5219757 2.0347435e-3 1.3653978e-4 P01_45_1-P01_52_1 239 0.4712498 -0.5226352 1.3921095e-3 1.3539851e-4 P01_53_1-P01_56_1 142 0.4746477 -0.5203241 8.6392465e-4 1.3356417e-4 P01_57_1-P01_59_1 107 0.4747909 -0.5253515 1.2616959e-3 1.3577596e-4 P01_60_2-P14N_29_1 105 0.4771914 -0.5168202 1.0539244e-4 1.3202413e-4 P14N_28_1-P14N_21_1 267 0.4763509 -0.5223087 6.2960998e-4 1.3445401e-4 P14N_20_1-P14N_4_1 459 0.4688899 -0.5227800 2.8376767e-3 1.3873165e-4 P14N_30_1-P14N_35_1 212 0.4731548 -0.5194302 1.4379132e-3 1.3444478e-4 P14N_36_1-P14N_38_1 35 0.4893230 -0.5237080 -9.4980732e-4 1.3213583e-4 P14N_39_1-P14N_54_1 543 0.4774736 -0.5235095 1.8334515e-3 1.3497810e-4 P14N_55_1-P14N_73_1 604 0.4696442 -0.5195310 2.2965664e-3 1.3703207e-4 1P14N_74_2-P14N_109_1 1174 0.4747268 -0.5257560 1.7272031e-3 1.3737072e-4 P14N_109_2-P14N_125_1 584 0.4759044 -0.5260304 1.8433363e-3 1.3730910e-4 1P14N_126_1-P14N_155_1 1028 0.4821183 -0.5331461 1.7173733e-3 1.3781520e-4 P14N_156_1-P14N_171_1 525 0.4786612 -0.5326933 2.1517595e-3 1.3916129e-4 P14N_172_1-P14N_185_1 328 0.4577516 -0.5081243 3.2346432e-3 1.4062034e-4 P14C_48_1-P14C_36_1 376 0.4586324 -0.5078367 3.1528881e-3 1.3845760e-4 P14C_35_1-P14C_19_1 501 0.4590327 -0.5006313 2.9939197e-3 1.3471839e-4 P14C_18_1-P14C_1_1 395 0.4587594 -0.5018013 3.1010637e-3 1.3465825e-4 _________________________________________________________________________________ Figure 3.1.12: Difference between the CTD oxygen and the bottle oxygen for after the post-cruise calibration for leg 1. Lower two panels show histogram of the difference. Figure 3.1.13: Difference between the optode oxygen and the bottle oxygen for after the post-cruise calibration for leg 2. Lower two panels show histogram of the difference. Table 3.1.13: Difference between the CTD oxygen and the bottle oxygen after the post-cruise calibration. Mean and standard deviation (Sdev) are calculated for the data below and above 950 dbar. Number of data used is also shown. ______________________________________________________________ Pressure ≥ 950 dbar Pressure < 950 dbar ---------------------------- ---------------------------- Mean Sdev Mean Sdev Number (µmol/kg) (µmol/kg) Number (µmol/kg) (µmol/kg) ------ --------- --------- ------ --------- --------- Leg 1 2698 -0.13 0.86 1876 -0.04 13.05 Leg 2 2096 -0.03 0.72 1642 -0.12 3.10 ______________________________________________________________ REFERENCES Fukasawa, M., T. Kawano and H. Uchida (2004): Blue Earth Global Expedition collects CTD data aboard Mirai, BEAGLE 2003 conducted using a Dynacon CTD traction winch and motion-compensated crane, Sea Technology, 45, 14-18. Kawano, T. and H. Uchida (Eds.) (2007): WHP P03 Revisit Data Book, 208 pp., JAMSTEC, Yokosuka, Kanagawa, Japan. Uchida, H., K. Ohyama, S. Ozawa, and M. Fukasawa (2007): In situ calibration of the Sea-Bird 9plus CTD thermometer, J. Atmos. Oceanic Technol., 24, 1961-1967. Uchida, H., T. Kawano, I. Kaneko, and M. Fukasawa (2008): In situ calibration of optode-based oxygen sensors, J. Atmos. Oceanic Technol., 25, 2271-2281. ******************************************************************************** ******************************************************************************** UPDATE OF CTD OXYGEN DATA FOR THE CRUISES MR07-04 AND MR07-06 Hiroshi Uchida/JAMSTEC (September 24, 2009) 1. Introduction The CTD oxygen data were updated after the data book was published by Kawano et al. (2009). In the data book, data from two oxygen optode sensors (Oxygen Optode 3830; Aanderaa Data Instruments AS, Bergen, Norway, and R1NKO; JFE Alec Co. Ltd., Kobe, Japan) were combined and used because data quality of the SBE 43 oxygen sensor was relatively bad (Kawano et al., 2009) for the cruise MR07-04. Data from the two oxygen optode sensors were combined because the Optode 3830 had a slow time response without pressure hysteresis and the RINKO had a fast time response with pressure hysteresis. The time-dependent, pressure-induced effect (pressure hysteresis) on the sensing foil of the RINKO was similarly observed in the SBE 43 data. Recently, a correction method of the pressure hysteresis was developed for the SBE 43 (Sea-Bird Electronics, 2009), and the correction method was successfully applied to the RINKO (Murata, 2009). Therefore, the RINKO data were reprocessed, calibrated, and used as the CTD oxygen data for the cruises MR07-04 and MR07-06. 2. Data processing The RINKO data were reprocessed from the raw data. The time-dependent, pressure- induced effect (pressure hysteresis) of the RINKO was corrected for both profile and bottle data by using RINKOCOR (original module, version 1.0) and RINKOCORROS (original module, version 1.0) after the module TCORP. The calibration coefficients, H1 (amplitude of hysteresis correction), H2 (curvature function for hysteresis), and H3 (time constant for hysteresis) were determined empirically as: H1 = 0.0065 for the RINKO prototype I with the foil A or C H1 = 0.0055 for the RINKO prototype I with the foil B or prototype II with the foil D H1 = 0.0060 for the RINKO prototype II with the foil C H2 = 5000 dbar H3 = 2000 seconds. Type of the prototype and foil is listed in Table 1. Data from the RINKO sensors are systematically delayed with respect to depth because of the slow response time compared with the CTD sensors. This delay was compensated by 1 second advancing sensor output (voltage) relative to the CTD temperature data by using the SEASOFT module ALIGNCTD. To remove spikes of the data, the process of the DESPIKE was also performed for the RINKO data. The rest of the data processing was not changed from the data book (Kawano et al., 2009). Table 1: Type of the prototype and foil used in the cruises. ________________________________________________________________________________ Cruise RINKO Foil Note --------- ------------------------ ---- -------------------------------------- MR07-04 Prototype I (UV LED) A MR07-06_1 Prototype I B MR07-06_2 Prototype I C Stations from P14N_109_2 to P14N_175_1 Prototype II (Green LED) D Stations from P14N_176_1 to P14N_185_1 Prototype II C Stations from P14C_48_1 to P14C_1_1 ________________________________________________________________________________ 3. Post-cruise calibration The pressure-hysteresis corrected RINKO data was calibrated by the Stern-Volmer equation, basically according to a method by Uchida et al. (2008) with slight modification: [O2] (µmol/l) = (V0 / V - 1)/ KSV and KSV = C0 + C1 x T + C2 x T2 V0 = 1 + C3 x T V = C4 + C5 x V + C6 x t + C7 t x Vb where Vb is the RINKO output (voltage), V0 is voltage in the absence of oxygen, T is temperature (°C), and t is time (days). The V0 and V are normalized by the phase shift in the absence of oxygen at 0°C, and the time drift of the RINKO output was corrected. The oxygen concentration is calculated by using the in situ calibrated CTD temperature data. The pressure-compensated oxygen concentration [O2c] can be calculated as follows. [O2c] = O2 (1 + Cp/1000) or [O2c] = O2 (1 + CpP /1000)(^1/3) where p is CTD pressure (dbar) and Cp is the compensation coefficient. Since the sensing foil of the optode is permeable only to gas and not to water, the optode oxygen must be corrected for salinity. The salinity-compensated oxygen can be calculated by multiplying the factor of the effect of salt on the oxygen solubility (Garcia and Gordon, 1992). Garcia and Gordon (1992) have recommended the use of the solubility coefficients derived from the data of Benson and Krause. The pressure-compensation coefficient (Cp) and the coefficient for the V0 (C3) were empirically estimated in advance except for the C for the cruise MR07-06 leg 1 (Table 2). The C for the cruise MR07-06 leg 1 was determined simultaneously with the remaining coefficients. The remaining seven coefficients (C0, C1, C2, C4, C5, C6, and C7) were determined by minimizing the sum of absolute deviation with a weight from the bottle oxygen data. The revised quasi- Newton method (the FORTRAN subroutine DMINF1 from the Scientific Subroutine Library II, Fujitsu Ltd., Kanagawa, Japan) was used to determine the sets. The weight was given as a function of pressure as: Weight = min[10, exp{log(10) P / PR}] where PR is threshold of the pressure (950 dbar). The post-cruise calibrated temperature and salinity data were used for the calibration. The coefficients were determined for some groups of the CTD stations. The calibration coefficients are listed in Table 3. The results of the post-cruise calibration for the RINKO oxygen are summarized in Table 4 and shown in Figs. 1, 2, and 3. References Garcia, H.E. and L.I. Gordon (1992): Oxygen solubility in seawater: Better fitting equations. Limnol. Oceanogr., 37 (6), 1307-1312. Kawano, T., H. Uchida and T. Doi (2009): WHP P01, P14 REVISIT DATA BOOK, 212 pp., JAMSTEC, Yokosuka, Japan. Murata, A. (Ed.) (2009): R/V Mirai Cruise Report, MR09-01, JAMSTEC, Yokosuka, Japan. Sea-Bird Electronics (2009): SBE 43 dissolved oxygen (DO) sensor - hysteresis corrections, Application note no. 64-3, 7pp. Uchida, H., T. Kawano, I. Kaneko, and M. Fukasawa (2008): In situ calibration of optode-based oxygen sensors, J. Atmos. Oceanic Technol., 25, 2271-2281. Table 2: Calibration coefficients for the V0 (C3) and for the pressure-compensation equation (Ce). The pressure- compensation equation is also shown. ______________________________________________________ Groups C3 Cp Pressure-compensation equation ------ ------- ----- ------------------------------ 01-06 -0.0022 0.109 O2(1 + CpP/1000)(^1/3) 07 -0.0028 0.055 O2(1 + CpP/1000) 08 -0.0028 0.056 O2(1 + CpP/1000) 09 -0.0028 0.057 O2(1 + CpP/1000) 10-11 -0.0028 0.055 O2(1 + CpP/1000) 12 -0.0028 0.054 O2(1 + CpP/1000) 13 -0.0028 0.053 O2(1 + CpP/1000) 14-15 -0.0028 0.054 O2(1 + CpP/1000) 16 -0.0028 0.053 O2(1 + CpP/1000) 17 -0.0028 0.051 O2(1 + CpP/1000) 18 -0.0028 0.056 O2(1 + CpPI1000) 19 -0.0028 0.055 O2(1 + CpP/1000) 20 -0.0028 0.057 O2(1 + CpP/1000) 21 -0.0028 0.056 O2(1 + CpP/1000) 22 -0.0028 0.058 O2(1 + CpP/1000) 23-41 -0.0021 0.100 O2(1 + CpP/1000)(^1/3) 42 -0.0024 0.066 O2(1 + CpP/1000) 43-45 -0.0021 0.100 O2(1 + CpP/1000)(^1/3) ______________________________________________________ Group of CTD stations 01:P01_1_1-P01_18_1, 02:P01_19_1-P01_21_1, 03:P01_22_1-P01_26_1, 04:P01_27_1-P01_29_1, 05:P01_40_1-P01_44_1, 06:P01_58_2-P01_115_1, 07:P01_28_2, 08:P01_29_2-P01_30_1, 09:P01_32_1-P0131_1, 10: P01_33_1-P01_35_1, 11:P01_36_1-P01_37_1, 12:P01_38_1-P01_43_1, 13: P01_44_2-P01_46_1, 14:P01_47_1-P01_55_1, 15:P01_56_1-P01_61_2, 16: P14N_29_1-P14N_16_1, 17:P14N_15_1-P14N_5_1, 18:P14N_1_1-P14N_4_1, 19:P14N_30_1-P14N_49_1, 20:P14N_50_1-P14N_63_1, 21:P14N_64_1-P14N_73_1, 22:P14N_74_1-P14N_109_1, 23:P14N_109_2-P14N_110_1, 24:P14N_111_1-P14N_112_1, 25:P14N_113_1-P14N_115_1, 26:P14N_116_1-P14N_118_1, 27:P14N_119_1-P14N_120_1, 28:P14N_121_1-P14N_122_1, 29:P14N_123_1-P14N_124_1, 30:P14N_125_1-P14N_126_1, 31:P14N_127_1-P14N_130_1, 32:P14N_131_1-P14N_135_1, 33:P14N_136_1-P14N_141_1, 34:P14N_142_1-P14N_144_1, 35:P14N_145_1-P14N_147_1, 36:P14N_148_1-P14N_149_1, 37:P14N_150_1-P14N_154_1, 38:P14N_155_1-P14N_160_1, 39:P14N_161_1-P14N_164_1, 40:P14N_165_1-P14N_170_1, 41:P14N_171_1-P14N_175_1, 42:P14N_176_1-P14N_185_1, 43:P14C 48_1-P14C 49_1, 44: P14C 52_1-P14C_19_1, 45:P14C_18_1-P14C_1_1 Table 3: Calibration coefficients for the RINKO oxygen sensors. The group of the CTD stations is same as that shown in Table 2. _____________________________________________________________________________________ Group C0 C1 C2 C4 C5 C6 C7 ------------------------------------------------------------------------------------- MRO7-04 01 5.78769e-3 1.88171e-4 5.21610e-6 -0.229888 0.254955 -2.43960e-3 1.74806e-3 02 5.76112e-3 2.05112e-4 4.20869e-6 -0.247620 0.261781 2.66538e-3 -1.91261e-4 03 5.58601e-3 1.94710e-4 3.60579e-6 -0.212837 0.254295 -2.82424e-3 1.37946e-3 04 5.52573e-3 2.53171e-4 -9.45815e-7 -0.171401 0.242433 -8.92725e-3 3.03414e-3 05 5.50404e-3 1.54503e-4 6.20130e-6 -0.151539 0.241621 -4.59826e-3 1.44984e-3 06 5.33007e-3 1.84105e-4 3.53496e-6 -0.211406 0.257880 -9.26535e-4 5.21621e-4 MRO7-06 leg 1 07 6.55224e-3 2.12959e-4 7.32523e-6 -0.408829 0.281951 0.00000 0.00000 08 6.45822e-3 2.14475e-4 6.35186e-6 -0.417754 0.283925 1.81734e-2 -2.32210e-3 09 6.30664e-3 1.19267e-4 1.02338e-5 -0.374523 0.274294 -1.66424e-3 3.47136e-3 10 6.29642e-3 1.30131e-4 1.20613e-5 -0.402078 0.283497 7.75298e-3 -8.98322e-5 11 6.40532e-3 -6.71557e-6 2.64522e-5 -0.367286 0.275724 -4.93850e-3 2.98357e-3 12 6.05874e-3 9.93107e-5 1.32774e-5 -0.372592 0.278740 2.17949e-3 1.09013e-3 13 6.03637e-3 8.01334e-5 1.58469e-5 -0.380144 0.285135 3.33545e-3 9.87750e-5 14 5.94341e-3 8.92774e-5 1.27029e-5 -0.354093 0.276789 6.36922e-4 1.12659e-3 15 6.01971e-3 1.30065e-4 1.09592e-5 -0.344272 0.277559 -1.21930e-3 1.10575e-3 16 5.85814e-3 1.51238e-4 8.52212e-6 -0.360336 0.280217 9.57900e-4 7.46866e-4 17 5.76211e-3 2.02794e-4 7.38395e-6 -0.366150 0.286581 5.09066e-4 5.41219e-4 18 5.87643e-3 1.30110e-4 1.47536e-5 -0.237946 0.233457 -6.75607e-3 3.56108e-3 19 5.71949e-3 1.68597e-4 5.73708e-6 -0.347475 0.284820 3.14416e-4 4.89874e-4 20 5.70894e-3 1.87827e-4 4.02373e-6 -0.366959 0.293059 1.27735e-3 1.13690e-4 21 5.80033e-3 1.95761e-4 4.35824e-6 -0.375413 0.302121 1.28422e-3 -1.60368e-4 22 5.76787e-3 1.80175e-4 4.38162e-6 -0.352233 0.298371 7.66105e-4 -8.16506e-5 MRO7-06 leg 2 23 5.44937e-3 1.65251e-4 2.76961e-6 -0.199505 0.239278 3.09346e-3 4.15719e-3 24 5.54177e-3 1.61531e-4 3.18336e-6 -0.228340 0.249132 1.83265e-2 -2.15387e-3 25 5.42048e-3 1.83287e-4 2.07555e-6 -0.192462 0.241038 -4.07720e-4 2.49626e-3 26 5.45889e-3 1.64536e-4 2.88640e-6 -0.192265 0.243283 -1.88936e-3 2.06094e-3 27 5.35393e-3 1.60876e-4 2.80193e-6 -0.138462 0.225840 -1.67471e-2 7.32406e-3 28 5.38960e-3 1.85479e-4 2.07045e-6 -0.213034 0.253068 4.39692e-3 -6.93024e-4 29 4.91234e-3 1.69346e-4 1.34107e-6 -0.138257 0.236248 -7.47363e-3 3.11840e-3 30 5.29710e-3 1.86796e-4 1.85766e-6 -0.190758 0.248364 -7.30369e-4 7.20446e-4 31 5.29129e-3 1.84807e-4 2.06747e-6 -0.197598 0.249238 -1.06270e-4 8.01728e-4 32 5.35606e-3 1.85394e-4 2.29483e-6 -0.188360 0.247306 -2.34961e-3 1.19205e-3 33 5.23672e-3 1.76559e-4 2.52414e-6 -0.195684 0.252713 -1.02750e-3 5.84364e-4 34 5.36437e-3 1.71687e-4 3.34220e-6 -0.287883 0.282532 7.97539e-3 -2.50022e-3 35 5.07284e-3 1.80971e-4 2.12433e-6 -0.238973 0.284333 3.72564e-3 -2.43784e-3 36 5.16377e-3 1.77869e-4 2.70794e-6 -0.209220 0.246022 1.93576e-4 1.20839e-3 37 5.18307e-3 1.78043e-4 2.97573e-6 -0.238163 0.274864 2.18383e-3 -1.17744e-3 38 5.18550e-3 1.72648e-4 3.33928e-6 -0.224989 0.271406 6.54311e-4 -6.88668e-4 39 4.73947e-3 1.70534e-4 2.09447e-6 -0.237428 0.284716 3.34250e-3 -1.69718e-3 40 4.53781e-3 1.65093e-4 1.75764e-6 -0.113741 0.233677 -4.24469e-3 1.73284e-3 41 4.60581e-3 1.62495e-4 2.23853e-6 -0.179177 0.254948 -5.72044e-4 4.97947e-4 42 3.51665e-3 1.16255e-4 2.37582e-6 -0.413749 0.300233 -3.24861e-3 1.34826e-3 43 4.24252e-3 1.22672e-4 3.09423e-6 0.122545 0.051831 -3.05446e-2 1.20623e-2 44 3.77773e-3 1.20741e-4 2.44550e-6 -0.507127 0.309672 4.31407e-4 -1.68904e-4 45 3.40682e-3 1.16962e-4 1.79879e-6 -0.529886 0.325479 1.74046e-3 -6.22456e-4 _____________________________________________________________________________________ Table 4: Difference between the RINKO oxygen and the bottle oxygen after the post-cruise calibration. Mean and standard deviation (Sdev) are calculated for the data below and above 950 dbar. Number of data used is also shown. ____________________________________________________________________ Cruise Pressure ≥ 950 dbar Pressure < 950 dbar ---------------------------- ---------------------------- Mean Sdev Mean Sdev Number (µmol/kg) (µmol/kg) Number (µmol/kg) (µmol/kg) ------ --------- --------- ------ --------- --------- MRO7-04 1510 -0.01 0.22 1118 0.25 2.70 MRO7-061 2698 -0.01 0.18 1876 -0.07 1.31 MRO7-062 2095 -0.00 0.24 1642 -0.01 1.03 ____________________________________________________________________ Figure 1: Difference between the RINKO oxygen and the bottle oxygen after the post-cruise calibration for the cruise MRO7-04. Lower two panels show histogram of the difference. Figure 2: Same as Fig. 1, except for the cruise MRO7-06 leg 1. Figure 3: Same as Fig. 1, except for the cruise MRO7-06 leg 2. 3.2 Salinity 31 October 2008 (1) Personnel Takeshi Kawano (JAMSTEC) Fujio Kobayashi (MWJ) Naoko Takahashi (MWJ) Tatsuya Tanaka (MWJ) (2) Objectives Bottle salinities were measured to compare with CTD salinities for calibrating CTD salinities and for identifying leaking bottles (3) Instrument and Method (3.1) Salinity Sample Collection Samples for salinity measurement were collected and stored in 250-ml brown borosilicate glass bottleswith GL32 screw caps with PTFE liners. Each bottle was rinsed three times with sample water, and then the water was allowed to overflow the bottle for few seconds. Excess water was poured out until the water was level with the shoulder of the bottle. The caps were also thoroughly rinsed and then tightly screwed onto the bottles. The sealed bottles were rinsed with fresh water (cap side up) and dried on a towel. The bottles were stored upside down in a carrying case and brought to the laboratory for temperature equilibration. Samples were stored more than 12 hours in the laboratory where the salinity was to be measured. (3.2) Instruments and Method The measurements were conducted with two Guildline Autosal laboratory salinometers (Model 8400B S/N 62556 and S/N 62827), which were modified by the addition of a peristaltic-type sample intake pumps (provided by OSIL). Two digital platinum resistance thermometers (Model 9540) were used to measure temperature: one placed in the bath of the Autosal to measure the bath temperature, and the other placed beside the Autosal to measure the ambient temperature. The measurement system was almost same as Aoyama et al (2003). The Autosal and thermometers were connected to a laptop computer through Binary Coded Decimal output and GP-IB interfaces, respectively. When the function dial was turned to the 'read' setting, 31 readings of the double conductivity ratio were acquired after a pause of 5 seconds. Acquisition of the 31 readings took about 10 seconds. The double conductivity ratio of a sample was taken to be the median of the 31 readings. The temperature was taken to be the average of the values measured before and after readings of the double conductivity ratio. The salinometer was operated in the air-conditioned ship's laboratory at a bath temperature of 24°C. An ambient temperature varied from approximately 20°C to 24°C, while a bath temperature is very stable and varied within +/- 0.002°C on rare occasion. The double conductivity ratio (along with temperature) was sampled for the sixth and seventh fillings of the conductivity cell. If the difference between the double conductivity ratios obtained for these two fillings was smaller than 0.00002, the average of the two double conductivity ratios was used to calculate the salinity. If the difference was greater than or equal to 0.00003, we measured an additional filling of the cell. If the double conductivity ratio obtained for the additional filling did not satisfy the criterion specified above, we measured two additional fillings of the cell, and the median of the double conductivity ratios for the five fillings was used to calculate the salinity. Algorithm for practical salinity scale, 1978 (UNESCO, 1981) was employed to convert the conductivity ratios to salinities The measurements were typically conducted for 16 hours a day and the cell was rinsed by pure water every day and cleaned by ethanol or soap or both after the daily measurement. (3.3) Preliminary Result (i) MR07-04 Standard Seawater Standardization control was set to 452 and all the measurements were done by this setting. STNBY was 5398 +/- 0001 and ZERO was 0.00001 +/- 0.00001. We used IAPSO Standard Seawater batch P148 whose conductivity ratio was 0.99982 (double conductivity ratio is 1.99964) as the standard for salinity. We measured 37 bottles of P148 during routine measurement from Stn.1 to Stn.28 and 78 bottles from Stn.40 to Stn.115. Fig.3.2.1: History of Double conductivity ratio of P148 during Leg.1. X and Y axes represents date and double conductivity ratio, respectively. Fig.3.2.2: History of Double conductivity ratio of P148. X and Y axes represent time Fig.3.2.1 shows the history of double conductivity ratio of the Standard Seawater batch P148. During the period from 27, July to 4, August, the average of double conductivity ratio was 1.99985 and no drifts was calculated. Therefore we subtract 0.00001 from double conductivity ratio of samples measured during this period. Because of the trouble described in Section.1, measurement was interrupted for about 10 days. During the period from 13 August, double conductivity ratio of SSW was around 1.99862, however, after 28 August, it became smaller, probably due to cooling of room temperature. Therefore, we added 0.00002 to double conductivity ratio of samples measured from 13 August to 28 August, and 0.00003 to it measured after 28 August. Correction for the history of double conductivity ration after this correction was shown in Fig.3.2.2. After correction, the average of double conductivity ratio of 115 bottles of SSW became 1.999636 and the standard deviation was 0.00008, which is equivalent to 0.0002 in salinity. Sub-Standard Seawater We also measured sub-standard seawater periodically to monitor the conditions of the Autosal. Approximately 20 L of seawater collected from a deep layer and gravity filtered through a membrane filter (Millipore HA, pore size 0.45 µm) was used as sub-standard seawater. The sub-standard seawater was stored in an aged cubitainer with no headspace and stirred for at least 24 hours before use. Sub-standard seawater was measured every six samples in case of a sudden drift in the Autosal. During the whole measurements, there was no detectable sudden drift of the salinometer. Replicates We took 491 pairs of replicates. Fig.3.2.3 shows the histogram of the absolute difference between replicate samples. There were 4 bad measurements and 5 questionable measurements of replicate samples. Excluding these bad and questionable measurements, the average and standard deviation of the absolute deference of 482 pairs of replicate samples was 0.0018 and 0.00019 in salinity, respectively. Fig.3.2.3: The histogram of the absolute difference between replicate samples. (ii) MR07-06 Leg.1 Standard Seawater Leg.1 Standardization control was set to 460 and all measurements were done by this setting. STNBY was 5402 +/- 0001 and ZERO was 0.00001 +/- 0.00001. We used IAPSO Standard Seawater batch P148 whose conductivity ratio was 0.99982 (double conductivity ratio is 1.99964) as the standard for salinity. We measured 146 bottles of P148 during routine measurement. Fig.3.2.4 shows the history of double conductivity ratio of the Standard Seawater batch P148. Figure 3.2.4: The history of double conductivity ratio of the Standard Seawater batch P142. Drifts were calculated by fitting data from P148 to the equation obtained by the least square method (solid lines). Correction for the double conductivity ratio of the sample was made to compensate for the drift. After the drift correction, we add 0.00001 for the first and second set and 0.00002 for the third set to make the average to 1.99964. After these corrections, the standard deviation of 146 bottles becomes 0.000009, which is equivalent to 0.0002 in saliniy. Sub-Standard Seawater We also measured sub-standard seawater periodically to monitor the conditions of the Autosal. Approximately 20 L of seawater collected from a deep layer and gravity filtered through a membrane filter (Millipore HA, pore size 0.45 µm) was used as sub-standard seawater. The sub-standard seawater was stored in an aged cubitainer with no headspace and stirred for at least 24 hours before use. Sub-standard seawater was measured every six samples in case of a sudden drift in the Autosal. During the whole measurements, there was no detectable sudden drift of the salinometer. Figure 3.2.5: The histogram of the absolute difference between each pair of replicate samples in Leg.1. X axis is absolute difference in salinity and Y axis is frequency. Replicates We took 840 pairs of replicate. Fig.3.2.5 shows the histogram of the absolute difference between each pair of the replicate samples. There were 6 bad measurements in the replicate samples. Excluding these bad measurements, the standard deviation of the absolute difference in 834 pairs of the replicate samples was 0.00017 in salinity. (iii)MR07-06 Leg.2 Standard Seawater Standardization control was set to 464 and all measurements were done by this setting. STNBY was 5402 +/- 0001 and ZERO was 0.00001 +/- 0.00001.We used IAPSO Standard Seawater batch P148 as the standard for salinity. We measured 160 bottles of P148 during routine measurement. There were 2 bad bottles whose conductivities were extremely high. Data of these 2 bottles are not taken into consideration hereafter. Fig.3.2.6 shows the history of double conductivity ratio of the Standard Seawater batch P148. Drifts were calculated by fitting data from P148 to the equation obtained by the least square method (solid lines). Correction for the double conductivity ratio of the sample was made to compensate for the drift. After correction, the average of double conductivity ratio became 1.999625 and the standard deviation was 0.00008, which is equivalent to 0.0002 in salinity. We added 0.000015 to make an average to 1.99964. Sub-Standard Seawater We also measured sub-standard seawater periodically to monitor the conditions of the Autosal. Approximately 20 L of seawater collected from a deep layer and gravity filtered through a membrane filter (Millipore HA, pore size 0.45 µm) was used as sub-standard seawater. The sub-standard seawater was stored in an aged cubitainer with no headspace and stirred for at least 24 hours before use. Sub-standard seawater was measured every six samples in case of a sudden drift in the Autosal. During the whole measurements, there was no detectable sudden drift of the salinometer. Fig.3.2.6: History of Double conductivity ratio of P148 during Leg.2. X and Y axes represents date and double conductivity ratio, respectively. Replicates We took 749 pairs of replicate samples. Fig.3.2.7 shows the histogram of the absolute difference between each pair of the replicate samples. There were 4 questionable measurements in the replicate samples. Excluding these questionable measurements, the standard deviation of the absolute difference in 745 pairs of the replicate samples was 0.00016 in salinity. Figure 3.2.7: The histogram of the absolute difference between each pair of replicate samples in Leg.2. X axis is absolute difference in salinity and Y axis is frequency. REFERENCES Aoyama, M., T. Joyce, T. Kawano and Y. Takatsuki: Standard seawater comparison up to P129. Deep-Sea Research, I, Vol. 49, 1103••1114, 2002 UNESCO: Tenth report of the Joint Panel on Oceanographic Tables and Standards. UNESCO Tech. Papers in Mar. Sci., 36, 25 pp., 1981 3.3 Oxygen 9 Novem ber 2008 (1) Personnel Yuichiro Kumamoto (JAMSTEC) Kimiko Nishijima (MWJ) Keisuke Wataki (MWJ) Masanori Enoki (MWJ) Miyo Ikeda (MWJ) Yukiko Hayakawa (MWJ) (2) Objectives Dissolved oxygen is one of good tracers for the ocean circulation. Recent studies in the North Pacific indicated that dissolved oxygen concentration in intermediate layers decreased in basin-wide scale during the past decades. The causes of the decrease, however, are still unclear. During cruises of MR07-04 conducted from 24-Jul-07 to 03-Sep-07 and MR07-06 from 08-Oct-07 to 25-Dec-07, we measured dissolved oxygen concentration from surface to bottom layers at all the hydrocast stations along around 47°N in the subarctic North Pacific and along 179°E in the central Pacific. These stations reoccupied the WHP-P01 (1985), WHP-P14N (1993), and WHP-P14C (1992) stations. Our purpose is to evaluate temporal changes in dissolved oxygen in the Pacific Ocean between the 1980/90s and 2007. (3) Reagents Pickling Reagent I: Manganous chloride solution (3M) Pickling Reagent II: Sodium hydroxide (8M)/sodium iodide solution (4M) Sulfuric acid solution (5M) Sodium thiosulfate (0.025M) Potassium iodate (0.001667M) CSK standard of potassium iodate: Lot EWL3818, Wako Pure Chemical Industries Ltd., 0.0100N (4) Instruments Burette for sodium thiosulfate and potassium iodate: APB-510 manufactured by Kyoto Electronic Co. Ltd./10 cm3 of titration vessel Detector: Automatic photometric titrator, DOT-01 manufactured by Kimoto Electronic Co. Ltd. (5) Seawater sampling Following procedure is based on a determination method in the WHP Operations Manual (Dickson, 1996). Seawater samples were collected from 12-liters Niskin sampler bottles attached to the CTD-system. Seawater for bottle oxygen measurement was transferred from the Niskin sampler bottle to a volume calibrated glass flask (ca. 100 cm3). Three times volume of the flask of seawater was overflowed. Sample temperature was measured by a thermometer during the overflowing. Then two reagent solutions (Reagent I, II) of 0.5 cm3 each were added immediately into the sample flask and the stopper was inserted carefully into the flask. The sample flask was then shaken vigorously to mix the contents and to disperse the precipitate finely throughout. After the precipitate has settled at least halfway down the flask, the flask was shaken again to disperse the precipitate. The sample flasks containing pickled samples were stored in a laboratory until they were titrated. (6) Sample measurement At least two hours after the re-shaking, the pickled samples were measured on board. A magnetic stirrer bar and 1 cm3 sulfuric acid solution were added into the sample flask and stirring began. Samples were titrated by sodium thiosulfate solution whose molarity was determined by potassium iodate solution. Temperature of sodium thiosulfate during titration was recorded by a thermometer. We measured dissolved oxygen concentration using two sets of the titration apparatus, named DOT-1 and DOT-3. Dissolved oxygen concentration (µmol kg-1) was calculated by the sample temperature during the sampling, CTD salinity, flask volume, and titrated volume of the sodium thiosulfate solution. (7) Standardization Concentration of sodium thiosulfate titrant (ca. 0.025M) was determined by potassium iodate solution. Pure potassium iodate was dried in an oven at 130°C. 1.7835 g potassium iodate weighed out accurately was dissolved in deionized water and diluted to final volume of 5 dm3 in a calibrated volumetric flask (0.001667M). 10 cm3 of the standard potassium iodate solution was added to a flask using a volume-calibrated dispenser. Then 90 cm3 of deionized water, 1 cm3 of sulfuric acid solution, and 0.5 cm3 of pickling reagent solution II and I were added into the flask in order. Amount of titrated volume of sodium thiosulfate (usually 5 times measurements average) gave the molarity of the sodium thiosulfate titrant. Table 3.3.1 and 3.3.2 show result of the standardization during the two cruises. Error (C.V.) of the standardization was 0.02 + 0.01%, c.a. 0.05 µmol kg-1. (8) Determination of the blank The oxygen in the pickling reagents I (0.5 cm3) and II (0.5 cm3) was assumed to be 3.8 x 10-8 mol (Murray et al., 1968). The blank from the presence of redox species apart from oxygen in the reagents (the pickling reagents I, II, and the sulfuric acid solution) was determined as follows. 1 and 2 cm3 of the standard potassium iodate solution were added to two flasks respectively. Then 100 cm3 of deionized water, 1 cm3 of sulfuric acid solution, and 0.5 cm3 of pickling reagent solution II and I each were added into the two flasks in order. The blank was determined by difference between the two times of the first (1 cm3 of KIO3) titrated volume of the sodium thiosulfate and the second (2 cm3 of KIO3) one. The results of three-time blank determinations were averaged and listed in Table 3.3.1 (MR07-04) and Table 3.3.2 (MR07-06). During MR07-04 cruise, the averaged blank of DOT-3 was -0.010 ± 0.001 (S.D., n=17) cm3. That of DOT-1 decreased from -0.003±0.001 (S.D., n=4) to -0.009 ± 0.002 (S.D., n=12) cm3 on July 31 because the pickling reagents for DOT-1 were replaced. During MR07-06 cruise, The averaged blank values for DOT-1 and DOT-3 before December 20 were -0.007 ± 0.001 (S.D., n=30) and -0.007 ± 0.001 (S.D., n=29) cm3, respectively. After the day, the values of the blank increased by about 0.005 cm3 in the sample measurements for P14C-001~-009 because we replaced the pickling reagents II solution. We also confirmed that there was no systematic bias in the blank determination between the DOT-1 and DOT-3 measurements on the both cruises. Table 3.3.1: Results of the standardization and the blank determinations during MR07-04. | KIO3 | DOT-1 (cm3) | DOT-3 (cm3) | Samples Date (UTC) | # ID No. | Na2S2O3 E.P. blank | Na2S2O3 E.P. blank | (Stations) ---------- | - -------------- | -------------- ----- ------ | -------------- ----- ------ | ---------------------------------------------------------------------------- 2007/07/26 | 1 20070619-05-02 | 20070613-01-03 3.960 -0.002 | 20070613-01-04 3.952 -0.011 | P01-001,002,003,004,005,006,007 2007/07/27 | 1 20070619-05-03 | 20070613-02-03 3.959 -0.003 | 20070613-02-04 3.950 -0.012 | P01-008,009,010,011,012 2007/07/28 | 1 20070619-05-04 | 20070413-03-01 3.968 -0.003 | 20070413-03-02 3.962 -0.011 | P01-013,014,015,016,017,018 2007/07/30 | 1 20070619-05-05 | 20070413-03-01 3.968 -0.003 | 20070413-03-02 3.960 -0.010 | P01-019,020,021,022,023,024 (DOT-01) 2007/07/30 | 1 20070619-05-06 | 20070413-03-02 3.961 -0.011 | | P01-019,020,021,022,023,024 (DOT-03) 2007/07/31 | 1 20070619-05-07 | 20070613-03-03 3.961 -0.011 | 20070613-03-04 3.959 -0.011 | P01-025,026,027,028 2007/08/12 | 2 20070619-06-01 | 20070413-03-03 3.960 -0.009 | 20070413-03-04 3.962 -0.011 | P01-040,044 2007/08/14 | 2 20070619-06-02 | 20070413-04-01 3.960 -0.010 | 20070413-04-02 3.960 -0.011 | P01-058,060,061,062,063 2007/08/15 | 2 20070619-06-03 | 20070413-04-01 3.962 -0.009 | 20070413-04-02 3.961 -0.010 | P01-064,065,066,067,068 2007/08/17 | 2 20070619-06-04 | 20070413-04-03 3.960 -0.012 | 20070413-04-04 3.962 -0.011 | P01-069,070,071,072,073,074 2007/08/19 | 2 20070619-06-05 | 20070413-04-03 3.962 -0.006 | 20070413-04-04 3.962 -0.010 | P01-X15,076,077,078,079,080 2007/08/21 | 2 20070619-06-06 | 20070413-05-01 3.961 -0.009 | 20070413-05-02 3.959 -0.010 | P01-081,082,083,084,085,086 2007/08/23 | 2 20070619-06-07 | 20070413-05-01 3.961 -0.008 | 20070413-05-02 3.959 -0.009 | P01-X16,087,088,089 2007/08/24 | 2 20070619-06-08 | 20070413-05-03 3.959 -0.009 | 20070413-05-04 3.961 -0.010 | P01-090,092,X17,094,095 2007/08/25 | 3 20070619-07-01 | 20070413-05-03 3.959 -0.008 | 20070413-05-04 3.960 -0.011 | P01-096,097,098,099,100,101 2007/08/27 | 3 20070619-07-02 | 20070413-06-01 3.957 -0.010 | 20070413-06-02 3.958 -0.011 | P01-102,103,104,105,106,107 2007/08/28 | 3 20070619-07-03 | 20070413-06-01 3.958 -0.012 | 20070413-06-02 3.960 -0.008 | P01-108,109,110,111,112,113,114,115 2007/10/09 | 4 20070619-09-02 | 20070613-03 3.951 -0.008 | 20070613-03 3.952 -0.007 | P01-028,029,030,032 2007/10/12 | 4 20070619-09-03 | 20070613-03 3.951 -0.007 | 20070613-03 3.952 -0.007 | P01-031,033,034,035,036,037 2007/10/14 | 4 20070619-09-04 | 20070613-05-01 3.953 -0.006 | 20070613-05-02 3.952 -0.005 | P01-038,039,040,041,042,X13,043 2007/10/16 | 4 20070619-09-05 | 20070613-05-01 3.953 -0.006 | 20070613-05-02 3.954 -0.007 | P01-044,045,046,047 2007/10/17 | 4 20070619-09-06 | 20070613-05-03 3.953 -0.006 | 20070613-05-04 3.951 -0.008 | P01-048,049,050,051,052,053,054 2007/10/18 | 4 20070619-09-07 | 20070613-05-03 3.952 -0.007 | 20070613-05-04 3.952 -0.008 | P01-055,056,057,058,059,060 2007/10/20 | 4 20070619-09-08 | 20070613-06-01 3.956 -0.009 | 20070613-06-02 3.956 -0.009 | P01-061,P14N-029,028,027,026,025,024 2007/10/22 | 5 20070619-10-01 | 20070613-06-01 3.957 -0.005 | 20070613-06-02 3.957 -0.007 | P14N-023,022,021,020,019 2007/10/23 | 5 20070619-10-02 | 20070613-06-03 3.957 -0.006 | 20070613-06-04 3.956 -0.006 | P14N-018,017,016,015,014,013,012,011,010,009,008,007,006,005,004,003,002,001 2007/10/29 | 5 20070619-10-04 | 20070613-07-01 3.957 -0.007 | 20070613-07-02 3.957 -0.008 | P14N-030,X01,032,033,034,035,036,037,038,039,040 2007/11/01 | 5 20070619-10-06 | 20070613-07-03 3.957 -0.007 | 20070613-07-04 3.957 -0.007 | P14N-041,042,043,044,045,046,047,048,049,051,052 2007/11/04 | 5 20070619-10-08 | 20070613-08-01 3.955 -0.007 | 20070613-08-02 3.956 -0.008 | P14N-053,054,055,056,057,058,059,060,061 2007/11/06 | 6 20070911-11-01 | 20070613-08-01 3.959 -0.006 | 20070613-08-02 3.960 -0.006 | P14N-062,063,064,X02 2007/11/07 | 6 20070911-11-02 | 20070613-08-03 3.957 -0.004 | 20070613-08-04 3.957 -0.008 | P14N-066,067,068,069,070,071,072,073 2007/11/11 | 6 20070911-11-03 | 20070613-08-03 3.959 -0.004 | 20070613-08-04 3.959 -0.008 | P14N-074,075,076,077 2007/11/12 | 6 20070911-11-04 | 20070613-09-01 3.955 -0.009 | 20070613-09-02 3.958 -0.007 | P14N-078,079,080,081,082,083,084,085,086,087,089,090 2007/11/14 | 6 20070911-11-06 | 20070613-09-03 3.955 -0.008 | 20070613-09-04 3.957 -0.008 | P14N-091,092,093,094,095,096,097,098,099,100,101,102 2007/11/18 | 6 20070911-11-08 | 20070613-10-01 3.956 -0.010 | 20070613-10-02 3.958 -0.008 | P14N-103,104,105,X04,107,108,109 2007/11/23 | 7 20070911-12-02 | 20070613-10-03 3.960 -0.007 | 20070613-10-04 3.959 -0.010 | P14N-109(2),110,111,112,113,114,115,116,117 2007/11/26 | 7 20070911-12-04 | 20070613-11-01 3.956 -0.007 | 20070613-11-02 3.955 -0.009 | P14N-118,119,120,121,122,123,124,125,126,127,128,129 2007/11/28 | 7 20070911-12-06 | 20070613-11-03 3.956 -0.007 | 20070613-11-04 3.957 -0.006 | P14N-130,131,132,133,134,135,136,137,138,139,140,141 2007/12/01 | 7 20070911-12-08 | 20070613-12-03 3.953 -0.006 | 20070613-12-01 3.956 -0.005 | P14N-142,143,144 2007/12/03 | 8 20070911-13-02 | 20070613-12-03 3.954 -0.007 | 20070613-12-01 3.956 -0.006 | P14N-145,146,147,148,149,150 2007/12/04 | 8 20070911-13-03 | 20070613-12-02 3.953 -0.006 | 20070613-12-04 3.956 -0.005 | P14N-151,152,153,154,155,156,157,158,159,160,161,162,163 2007/12/08 | 8 20070911-13-06 | 20070613-13-01 3.949 -0.006 | 20070613-13-02 3.952 -0.007 | P14N-164,165,166,167,168,169,170,171,172,173,174,175,176 2007/12/11 | 8 20070911-13-08 | 20070613-13-03 3.951 -0.004 | 20070613-13-04 3.952 -0.008 | P14N-177,178,179,180,181,182,183,184,185 2007/12/12 | 9 20070911-14-01 | 20070613-13-03 3.944 -0.006 | | P14N-184,185 2007/12/13 | 9 20070911-14-02 | 20070613-13-03 3.950 -0.007 | 20070613-13-04 3.950 -0.008 | P14C-049,048,052,051,050,047,046,045,044 2007/12/14 | 9 20070911-14-03 | 20070613-14-01 3.956 -0.006 | 20070613-14-02 3.958 -0.007 | P14C-043,042,041,040,039,038,037,036 2007/12/17 | 9 20070911-14-05 | 20070613-14-03 3.955 -0.008 | 20070613-14-04 3.956 -0.009 | P14C-032,031,030,029,028,027,026,025,024,023,022,021,020,019 2007/12/22 |10 20070911-15-01 | 20070613-15-01 3.966 0.002 | 20070613-15-02 3.967 0.004 | P14C-009,008,007 2007/12/22 |10 20070911-15-02 | 20070613-15-03 3.967 0.001 | 20070613-15-04 3.965 -0.001 | P14C-006,005,004,003,002,001 (9) Replicate sample measurement Replicate samples were taken from every CTD cast. The replicate sample pairs of good measurement (flagged 2) during MR07-04 and MR07-06 cruises were 236 and 739, respectively. The total number of the replicate pairs, 975 was about 9% of the total sample measurements. The standard deviations of the replicate measurements during MR07-04 and MR07-06 cruises were 0.10 and 0.08 µmol kg-1, respectively, which was calculated by a procedure (SOP23) in DOE (1994). In addition, there was no significant difference between the DOT-1 and DOT-3 measurements on the both cruises. Although there are several outlying data, relationship between the difference in the replicate sample pairs and sampling depth was not clear (Fig. 3.3.1). The difference also did not depend on measurement date (Fig. 3.3.2). In the hydrographic data sheet, the results of the replicate sample pairs were averaged and flagged "2" (see section 11). Figure 3.3.1: Differences of replicate sample pairs against sampling depth. Figure 3.3.2: Differences of replicate sample pairs against measurement date (Julian days). (10) CSK standard measurements The CSK standard is a commercial potassium iodate solution (0.0100 N) for analysis of dissolved oxygen. During MR07-04 and MR07-06 cruises, we measured six bottles of the CSK standard solutions (Lot EWL3818) against our KIO3 standards as samples (Table 3.3.3). A good agreement among them confirms that there was no systematic shift in our oxygen measurements during the two cruises. These values also agree with those measured in our previous cruises, MR07-03, suggesting comparability in the oxygen measurements among the three cruises. Table 3.3.3: Results of the CSK standard (Lot EWL3818) measurements on board. | | DOT-1 | DOT-3 | Date (UTC) | KIO3 ID No. | Conc.(N) error(N) | Conc.(N) error(N) | Remarks ---------- | -------------- | -------- -------- | -------- -------- | ------- 2007/10/07 | 20070619-08-05 | 0.010009 0.000002 | - - | MR07-06 2007/11/19 | 20070911-12-01 | 0.010003 0.000001 | 0.010000 0.000001 | MR07-06 2007/11/23 | 20070911-12-02 | 0.010000 0.000001 | 0.010003 0.000002 | MR07-06 2007/12/23 | 20070911-15-09 | 0.010006 0.000002 | 0.010007 0.000001 | MR07-06 2007/07/23 | 20070619-05-01 | 0.009999 0.000001 | 0.010002 0.000002 | MR07-04 2007/08/29 | 20070619-07-04 | 0.010004 0.000001 | 0.010006 0.000003 | MR07-04 2007/06/10 | 20070424-01-08 | - - | 0.010006 0.000002 | MR07-03 2007/07/24 | 20070425-01-06 | 0.010006 0.000003 | 0.010005 0.000002 | MR07-03 (11) Quality control flag assignment Quality flag values were assigned to oxygen measurements using the code defined in Table 0.2 of WHP Office Report WHPO 91-1 Rev.2 section 4.5.2 (Joyce et al., 1994). Measurement flags of 2 (good), 3 (questionable), 4 (bad), and 5 (missing) have been assigned (Tables 3.3.4). The replicate data were averaged and flagged 2 if both of them were flagged 2. If either of them was flagged 3 or 4, a datum with "younger" flag was selected. Thus we did not use flag of 6 (replicate measurements). For the choice between 2, 3, or 4, we basically followed a flagging procedure as listed below: a. Bottle oxygen concentration and difference between bottle oxygen and CTD oxygen at the sampling layer were plotted against CTD pressure. Any points not lying on a generally smooth trend were noted. b. Dissolved oxygen was then plotted against sigma-theta. If a datum deviated from a group of plots, it was flagged 3. c. Vertical sections against pressure and potential density were drawn. If a datum was anomalous on the section plots, datum flag was degraded from 2 to 3, or from 3 to 4. d. If the bottle flag was 4 (did not trip correctly), a datum was flagged 4 (bad). In case of the bottle flag 3 (leaking) or 5 (unknown problem), a datum was flagged based on the procedure shown above. Table 3.3.4: Summary of assigned quality control flags. _____________________________________________________ Flag Definition MR07-04 MR07-06 Total ---- ------------------- ------- ------- ------ 2 Good 2,628 8,312 10,940 3 Questionable 1 19 20 4 Bad 0 17 17 5 Not report (missing) 1 2 3 Total 2,630 8,350 10,980 _____________________________________________________ (12) Preliminary Results (12.1) Comparison with Winkler oxygen measurements by University of Washington on board At station MR07-06_P01-035, we conducted an inter-comparison of Winkler oxygen measurements between University of Washington (UW) and JAMSTEC on board. Seawater sample for UW was collected just after the oxygen sampling for JAMSTEC. The bottle oxygen concentrations in the samples from 15 Niskin bottles were analyzed separately by UW and JAMSTEC and compared each other. We got a very good agreement between UW and JAMSTEC results (Fig. 3.3.3). Figure 3.3.3: Comparison of bottle oxygen measurement between UW and JAMSTEC. A broken line shows a linear regression line whose correlation coefficient (r2) and standard error are 0.99997 and 0.567 "mol kg- 1, respectively. (12.2) Comparison of oxygen measurements at a cross point During MR07-06 cruise, we compared two profiles of bottle oxygen at a cross point, 47.0°N/179.5°E. The first and second casts were conducted on 20-Oct.- 2007 (MR07-06-P01-061) and 30-Oct.-2007 (MR07-06_P14N-X01), respectively. Below 1200 dbar, we got a good agreement between the first and second measurements (Fig. 3.3.4). We had also measured bottle oxygen concentration at the cross point during our previous cruise, MR07-04 (P01-061, 14-Aug.-2007). The oxygen profile in deep waters at the cross point of MR07-04 well agreed with those of MR07-06 (Fig. 3.3.4). Figure 3.3.4: Vertical profiles of bottle oxygen concentration at a cross point (47.0°N/179.5°E) during MR07-06 and MR07-04 cruises. (12.3) Decadal changes in dissolved oxygen along WHP-P01 Figure 3.3.5 shows zonal transects of dissolved oxygen along WHP-P01 in 2007. From 152°E (P01-028) to 179°E (P01-061), we re-occupied during MR07-06 in the October of 2007. The rest of the WHP-P01 stations were revisited during MR07-04 in the July and August of 2007. Difference in dissolved oxygen distribution between the eastern and western North Pacific can be distinguished. The boundary between the east and west is likely to be lying around 160°W. Dissolved oxygen concentrations in bottom waters in the west are higher than those in the east. The minimum concentration around 1000 m depth in the east was lower than that in the west. Figure 3.3.5: Zonal transects of dissolved oxygen along WHP-P01 in 2007 (Schlitzer, 2008). We compared dissolved oxygen in deep waters below 4000 m depth in 2007 with those in 1985 and 1999 along WHP-P01. The oxygen concentration in 2007 were slightly lower than those in 1985 and 1999 by 1.9 ± 0.8 (n=641) and 1.1 ± 1.2 (n=628) µmol kg-1, respectively. Despite of these small offsets in the deep layers, dissolved oxygen concentrations in the thermocline in 2007 were significantly higher than those in 1999. Distribution of differences in Apparent Oxygen Utilization (AOU) against water density between 1999 and 2007 (Fig. 3.3.6b) indicates that AOU (dissolved oxygen) decreased (increased) in waters just below seasonal mixing layer from 1999 to 2007. The maximum AOU decrease (about -50 µmol kg-1) was found in 26.6 σθ layer between 180° and 140°W approximately. This AOU change between 1999 and 2007 is opposite to that between 1985 and 1999 (Fig. 3.3.6a). (12.4) Decadal changes in dissolved oxygen along WHP-P14N/C Figure 3.3.7 shows meridional transects of dissolved oxygen along WHP-P14N/C in 2007. WHP-P14N and P14C lines are lying from the Bering Sea to the Fiji Island and from the Fiji Islands to New Zealand (the South Fuji Basin), respectively. The transect of WHP-P14N is characterized by an oxygen minimum in mid-layers from the Bering Sea to the equator. In the Central Pacific Basin from 20°N to 10°S, dissolved oxygen concentration in bottom water (Circumpolar Deep Water) is slightly high. In the South Fiji Basin, dissolved oxygen maximum was found in mid-layers around 600 - 800 m depth. We compared dissolved oxygen in deep waters below 4000 m depth in 2007 with those in 1992/93 along WHP-P14N/C. The oxygen data in 2007 were slightly lower than those in 1992/93 by 1.3 ± 2.0 (n=1106). Figure 3.3.8 shows distribution of differences in AOU against water density between 1992/93 and 2007. Except in the Bering Sea there was not large change in dissolved oxygen or AOU. The maximum AOU increase (about 40 µmol kg-1) was found in 26.6 σ layer in the Bering Sea. Small temporal changes in the tropical region between 20°N and 20°S may be caused by transition of mesoscale eddies. At a cross point between MR07- 04 and MR07-06 cruises (47°N/179°E), the intermediate AOU decreased by about 30 µmol kg-1 from 1999 to 2007 (see Fig. 3.3.6b). On the other hand, that decreased by about 10 µmol kg-1 from 1993 to 2007 (Fig. 3.3.8) These results imply that the intermediate AOU increased by about 20 µmol kg-1 from 1993 to 1999, which is consistent with the AOU increase between 1985 and 1999 at the cross point (see Fig. 3.3.6a). Figure 3.3.6: Distributions of differences of Apparent Oxygen Utilization, AOU (µmol kg-1) against density (σθ) between 1985 and 1999 (a) and between 1999 and 2007 (b). Contour intervals are 10 µmol/kg-1. Small dots indicate sampling layers for bottle oxygen. Sparse data hinder the comparison between 1999 and 2007 in shallow layers in the area to the east of 150°W (shaded area). Figure 3.3.7: Meridional transects of dissolved oxygen along WHP-P14N/C in 2007 (Schlitzer, 2008). Figure 3.3.8: Distributions of differences of AOU (µmol kg-1) against density (σθ) between 1992/93 and 2007. Contour intervals are 10 µmol kg-1. Small dots indicate sampling layers of dissolved oxygen in 2007. REFERENCES Dickson, A. (1996) Determination of dissolved oxygen in sea water by Winkler titration, in WHPO Pub. 91-1 Rev. 1, November 1994, Woods Hole, Mass., USA. DOE (1994) Handbook of methods for the analysis of the various parameters of the carbon dioxide system in sea water; version 2. A.G. Dickson and C. Goyet (eds), ORNL/CDIAC-74. Joyce, T., and C. Corry, eds., C. Corry, A. Dessier, A. Dickson, T. Joyce, M. Kenny, R. Key, D. Legler, R. Millard, R. Onken, P. Saunders, M. Stalcup, contrib. (1994) Requirements for WOCE Hydrographic Programme Data Reporting, WHPO Pub. 90-1 Rev. 2, May 1994 Woods Hole, Mass., USA. Schlitzer, R. (2008) Ocean Data View. WWW Page, http://odv.awi.de. Murray, C.N., J.P. Riley, and T.R.S. Wilson (1968) The solubility of oxygen in Winkler reagents used for determination of dissolved oxygen, Deep-Sea Res., 15, 237-238. 3.4 Nutrients 27 October 2008 (1) Personnel MR0704 cruise Michio AOYAMA (Meteorological Research Institute/Japan Meteorological Agency, Principal Investigator) Ayumi TAKEUCHI (Department of Marine Science, Marine Works Japan Ltd.) Takayoshi SEIKE (Department of Marine Science, Marine Works Japan Ltd.) Shunsuke MIYABE (Department of OD Science Technical Support, Marine Works Japan Ltd.) MR0706 cruise Michio AOYAMA (Meteorological Research Institute/Japan Meteorological Agency, Principal Investigator) LEG 1 Ayumi TAKEUCHI (Department of Marine Science, Marine Works Japan Ltd.) Junji MATSUSHITA (Department of Marine Science, Marine Works Japan Ltd.) Kohei MIURA (Marine Works Japan Ltd.) LEG 2 Kenichiro SATO (Department of Marine Science, Marine Works Japan Ltd.) Takayoshi SEIKE (Department of Marine Science, Marine Works Japan Ltd.) Kohei MIURA (Marine Works Japan Ltd.) (2) Objectives The objectives of nutrients analyses during the R/V MiraiMR0704 and MR0706 cruises, WOCE P1 and P14 revisited cruise in 2007, in the North Pacific are as follows; • Describe the present status of nutrients concentration with excellent comparability. • The determinants are nitrate, nitrite, phosphate and silicate. • Study the temporal and spatial variation of nutrients concentration based on the previous high quality experiments data of WOCE previous P1 cruises in 1985 and 1999, P14N/C cruises in 1992, GOESECS, IGY and so on. • Study of temporal and spatial variation of nitrate: phosphate ratio, so called Redfield ratio. • Obtain more accurate estimation of total amount of nitrate, phosphate and silicate in the interested area. • Provide more accurate nutrients data for physical oceanographers to use as tracers of water mass movement. (3) Summary of nutrients analysis We made 85 and 266 TRAACS800 runs for the samples at 88 in MR0704 and 273 stations in MR0706, respectively. The total amount of layers of the seawater sample reached up to 263 and 8319 for MR0704 and MR0706, respectively. We made duplicate measurement at all layers. (4) Instrument and Method (4.1) Analytical detail using TRAACS 800 systems (BRAN+LUEBBE) The phosphate analysis is a modification of the procedure of Murphy and Riley (1962). Molybdic acid is added to the seawater sample to form phosphomolybdic acid which is in turn reduced to phosphomolybdous acid using L-ascorbic acid as the reductant. Nitrate + nitrite and nitrite are analyzed according to the modification method of Grasshoff (1970). The sample nitrate is reduced to nitrite in a cadmium tube inside of which is coated with metallic copper. The sample stream with its equivalent nitrite is treated with an acidic, sulfanilamide reagent and the nitrite forms nitrous acid which reacts with the sulfanilamide to produce a diazonium ion. N-1-Naphthylethylene-diamine added to the sample stream then couples with the diazonium ion to produce a red, azo dye. With reduction of the nitrate to nitrite, both nitrate and nitrite react and are measured; without reduction, only nitrite reacts. Thus, for the nitrite analysis, no reduction is performed and the alkaline buffer is not necessary. Nitrate is computed by difference. The silicate method is analogous to that described for phosphate. The method used is essentially that of Grasshoff et al. (1983), wherein silicomolybdic acid is first formed from the silicate in the sample and added molybdic acid; then the silicomolybdic acid is reduced to silicomolybdous acid, or "molybdenum blue," using ascorbic acid as the reductant. The analytical methods of the nutrients during this cruise are similar with previous cruises (Uchida and Fukasawa, 2005). The flow diagrams and reagents for each parameter are shown in Figures 3.4.1- 3.4.4. (4.2) Nitrate Reagents Imidazole (buffer), 0.06 M (0.4% w/v) Dissolve 4 g imidazole, C3H4N2, in ca. 1000 ml DIW; add 2 ml concentrated HCl. After mixing, 1 ml Triton(R)X-100 (50% solution in ethanol) is added. Sulfanilamide, 0.06 M (1% w/v) in 1.2M HCl Dissolve 10 g sulfanilamide, 4-NH2C6H4SO3H, in 900 ml of DIW, add 100 ml concentrated HCl. After mixing, 2 ml Triton(R)X-100 (50%f solution in ethanol) is added. N-1-Napthylethylene-diamine dihydrochloride, 0.004 M (0.1%f w/v) Dissolve 1g NEDA, C10H7NHCH2CH2NH2 · 2HCl, in 1000 ml of DIW and add 10 ml concentrated HCl. Stored in a dark bottle. Figure3.4.1: 1ch. (NO3+NO2) Flow diagram. (4.3) Nitrite Reagents Sulfanilamide, 0.06 M (1% w/v) in 1.2 M HCl Dissolve 10g sulfanilamide, 4-NH2C6H4SO3H, in 900 ml of DIW, add 100 ml concentrated HCl. After mixing, 2 ml Triton(R)X-100 (50% solution in ethanol) is added. N-1-Napthylethylene-diamine dihydrochloride, 0.004 M (0.1% w/v) Dissolve 1 g NEDA, C10H7NHCH2CH2NH2 · 2HCl, in 1000 ml of DIW and add 10 ml concentrated HCl. Stored in a dark bottle. Figure3.4.2: 2ch. (NO2) Flow diagram. (4.4) Silicate Reagents Molybdic acid, 0.06 M (2% w/v) Dissolve 15 g Disodium Molybdate(VI) Dihydrate, Na2 MoO4 · 2H2O, in 980 ml DIW, add 8 ml concentrated H2 SO4 . After mixing, 20 ml sodium dodecyl sulphate (15% solution in water) is added. Oxalic acid, 0.6 M (5% w/v) Dissolve 50g Oxalic Acid Anhydrous, HOOC: COOH, in 950 ml of DIW. Ascorbic acid, 0.01M (3% w/v) Dissolve 2.5g L (+)-Ascorbic Acid, C6H8O6, in 100 ml of DIW. Stored in a dark bottle and freshly repared before every measurement. Figure3.4.3: 3ch. (SiO2) Flow diagram. (4.5) Phosphate Reagents Stock molybdate solution, 0.03M (0.8% w/v) Dissolve 8 g Disodium Molybdate(VI) Dihydrate, Na2 MoO4 · 2H2 O, and 0.17 g Antimony Potassium Tartrate, C8 H4 K2 O12 Sb2 · 3H2 O, in 950 ml of DIW and add 50 ml concentrated H2 SO4. Mixed Reagent Dissolve 0.8 g L (+)-Ascorbic Acid, C6 H8 O6 , in 100 ml of stock molybdate solution. After mixing, 2 ml sodium dodecyl sulphate (15% solution in water) is added. Stored in a dark bottle and freshly prepared before every measurement. Reagent for sample dilution Dissolve Sodium Hydrate, NaCl, 10 g in ca. 950 ml of DIW, add 50 ml Acetone and 4 ml concentrated H2 SO4. After mixing, 5 ml sodium dodecyl sulphate (15% solution in water) is added. Figure3.4.4: 4ch. (PO4) Flow diagram. (4.6) Sampling procedures Sampling of nutrients followed that oxygen, trace gases and salinity. Samples were drawn into two of virgin 10 ml polyacrylates vials without sample drawing tubes. These were rinsed three times before filling and vials were capped immediately after the drawing. The vials are put into water bath at 24 ± 1deg. C in 10 minutes before use to stabilize the temperature of samples in both MR0704 and MR0706. No transfer was made and the vials were set an auto sampler tray directly. Samples were analyzed after collection basically within 20 hours in MR0704 and 14 hours in MR0706. (4.7) Data processing Raw data from TRAACS800 were treated as follows; • Check baseline shift. • Check the shape of each peak and positions of peak values taken, and then change the positions of peak values taken if necessary. • Carry-over correction and baseline drift correction were applied to peak heights of each samples followed by sensitivity correction. • Baseline correction and sensitivity correction were done basically using liner regression. • Load pressure and salinity from CTD data to calculate density of seawater. • Calibration curves to get nutrients concentration were assumed second order equations. (5) Nutrients standards (5.1) Volumetric Laboratory Ware of in-house standards All volumetric glass- and polymethylpentene (PMP)-ware used were gravimetrically calibrated. Plastic volumetric flasks were gravimetrically calibrated at the temperature of use within 2-3 K. Volumetric flasks Volumetric flasks of Class quality (Class A) are used because their nominal tolerances are 0.05% or less over the size ranges likely to be used in this work. Class A flasks are made of borosilicate glass, and the standard solutions were transferred to plastic bottles as quickly as possible after they are made up to volume and well mixed in order to prevent excessive dissolution of silicate from the glass. High quality plastic (polymethylpentene, PMP, or polypropylene) volumetric flasks were gravimetrically calibrated and used only within 3-4 K of the calibration temperature. The computation of volume contained by glass flasks at various temperatures other than the calibration temperatures were done by using the coefficient of linear expansion of borosilicate crown glass. Because of their larger temperature coefficients of cubical expansion and lack of tables constructed for these materials, the plastic volumetric flasks were gravimetrically calibrated over the temperature range of intended use and used at the temperature of calibration within 3-4 K. The weights obtained in the calibration weightings were corrected for the density of water and air buoyancy. Pipettes and pipettors All pipettes have nominal calibration tolerances of 0.1% or better. These were gravimetrically calibrated in order to verify and improve upon this nominal tolerance. (5.2) Reagents, general considerations Specifications For nitrate standard, "potassium nitrate 99.995 suprapur" provided by Merck, CAS No. : 7757-91-1, was used. For phosphate standard, "potassium dihydrogen phosphate anhydrous 99.995 suprapur" provided by Merck, CAS No. : 7778-77-0, was sued. For nitrite standard, "sodium nitrate" provided by Wako, CAS No. : 7632-00-0, was used. And assay of nitrite was determined according JIS K8019 and assays of nitrite salts were 99.1%. We use that value to adjust the weights taken. For the silicate standard, we use "Silicon standard solution SiO2 in NaOH 0.5 mol/l CertiPUR" provided by Merck, CAS No. : 1310-73-2, of which lot number is HC623465 is used. The silicate concentration is certified by NIST-SRM3150 with the uncertainty of 0.5%. Ultra pure water Ultra pure water (MilliQ water) freshly drawn was used for preparation of reagents, higher concentration standards and for measurement of reagent and system blanks. Low-Nutrient Seawater (LNSW) Surface water having low nutrient concentration was taken and filtered using 0.45 µm pore size membrane filter. This water is stored in 20 liter cubitainer with paper box. The concentrations of nutrient of this water were measured carefully in May 2007. (5.3) Concentrations of nutrients for A, B and C standards Concentrations of nutrients for A, B and C standards are set as shown in Table 3.4.1. The C standard is prepared according recipes as shown in Table 3.4.2. All volumetric laboratory tools were calibrated prior the cruise as stated in chapter (i). Then the actual concentration of nutrients in each fresh standard was calculated based on the ambient, solution temperature and determined factors of volumetric lab. wares. Table 3.4.1: Nominal concentrations of nutrients for A, Band C standards. __________________________________________________________ A B C-1 C-2 C-3 C-4 C-5 C-6 C-7 ----- ---- --- --- --- --- --- --- --- NO3(%M) 45000 900 BA AY AX AV BF 55 BG NO2(%M) 4000 20 BA AY AX AV BF 1.2 BG SiO2(%M) 36000 2880 BA AY AX AV BF 170 BG PO4(%M) 3000 60 BA AY AX AV B 3.6 BG __________________________________________________________ Table 3.4.2: Working calibration stand ard recipes. ______________________________________________________ C Std. B-1 Std. B-2 Std. ------ -------- -------- C-6 30 ml 30 ml ______________________________________________________ B-1 Std.: Mixture of nitrate, silicate and phosphate B-2 Std.: Nitrite (5.4) Renewal of in-house standard solutions. In-house standard solutions as stated in (iii) were renewed as shown in Table 3.4.3. Table 3.4.3: Timing of renewal of in-house stand ards. ____________________________________________________________ NO3, NO2, SiO2, PO4 Renewal --------------------------- ----------------------------- A-1 Std. (NO3) maximum 1 month A-2 Std. (NO2) maximum 1 month A-3 Std. (SiO2) commercial prepared solution A-4 Std. (PO4) maximum 1 month B-1 Std. (mixture of NO3, SiO2, PO4) 8 days B-2 Std. (NO2) 8 days C Std. Renewal --------------------------- ----------------------------- C-6 Std. (mixture of 24 hours B-1 and B-2 Std.) Reduction estimation Renewal --------------------------- ----------------------------- D-1 Std. when A-1 Std. renewed (7200µm NO3) 43µm NO3 when C Std. renewed 47µm NO2 when C Std. renewed ____________________________________________________________ (6) Reference material of nutrients in seawater To get the more accurate and high quality nutrients data to achieve the objectives stated above, huge numbers of the bottles of the reference material of nutrients in seawater (hereafter RMNS) are prepared (Aoyama et al., 2007). In the previous world wide expeditions, such as WOCE cruises, the higher reproducibility and precision of nutrients measurements were required (Joyce and Corry, 1994). Since no standards were available for the measurement of nutrients in seawater at that time, the requirements were described in term of reproducibility. The required reproducibility was 1%, 1-2%, 1-3% for nitrate, phosphate and silicate, respectively. Although nutrient data from the WOCE one- time survey was of unprecedented quality and coverage due to much care in sampling and measurements, the differences of nutrients concentration at crossover points are still found among the expeditions (Aoyama and Joyce, 1996, Mordy et al., 2000, Gouretski and Jancke, 2001). For instance, the mean offset of nitrate concentration at deep waters was 0.5 µmol kg-1 for 345 crossovers at world oceans, though the maximum was 1.7 µmol kg-1 (Gouretski and Jancke, 2001). At the 31 crossover points in the Pacific WHP one-time lines, the WOCE standard of reproducibility for nitrate of 1% was fulfilled at about half of the crossover points and the maximum difference was 7% at deeper layers below 1.6 deg. C in potential temperature (Aoyama and Joyce, 1996). (6.1) RMNSs for this cruise RMNS lots BA, AY, AX, AV and BF, which cover full range of nutrients concentrations in the western North Pacific Ocean are prepared. 40 sets of BA, AY, AX, AV and BF are prepared. Since silicate concentration along P1 section was expected to be very high, we also prepared RMNS lot BG, of which silicate concentration is 255 µmol kg-1. When silicate concentration expected to exceed 170 µmol kg-1, we add RMNS lot BG as an additional standard as C-7. These RMNSs were renewed daily and analyzed every 2 runs on the same day. Eighty-five and 266 bottles of RMNS lot BC are prepared for MR0704 and MR0706, respectively, to use every analysis at every hydrographic station. These RMNS assignment were completely done based on random number. The RMNS bottles were stored at a room in the ship, REAGENT STORE, where the temperature was maintained around 24-26 deg. C. (6.2) Assigned concentration for RMNSs We assigned nutrients concentrations for RMNS lots BA, AY, AX, AV, BF, BC and BG as shown in Table 3.4.4. Table 3.4.4: Assigned concentration of RMNSs. _________________________________________________ unit: µmol kg -1 ----------------------------------------------- Nitrate Phosphate Silicate Nitrite -- ------- --------- -------- ------- AH 35.31 2.114 132.20 (0.02)* BA 0.07 0.068 1.60 0.02 AY 5.60 0.516 29.42 0.62 AX 21.42 1.619 58.06 0.35 AV 33.36 2.516 154.14 0.10 BF 41.39 2.809 150.61 0.02 BC 40.71 2.782 156.13 0.02 BG 36.85 2.570 254.42 0.06 _________________________________________________ * Concentration of nitrite for lot. AH did not assign. The value in the table is result of measurement on 7 Oct. 2007. (6.3) The homogeneity of RMNSs The homogeneity of lot BC and analytical precisions are shown in Table 3.4.5. These are for the assessment of the magnitude of homogeneity of the RMNS bottles those are used during the cruise. As shown in Table 3.4.5 and Table 3.4.6 the homogeneity of RMNS lot BC for nitrate and silicate are the same magnitude of analytical precision derived from fresh raw seawater in May 2005. The homogeneity for phosphate, however, exceeded the analytical precision at some extent. In May 2007, analytical precisions become better less than 0.1% and the homogeneity at lot BF and BG for nitrate, phosphate and silicate were 0.11-0.14%, 0.17-0.21%, 0.08-0.10%, respectively. Table 3.4.5: Homogeneity of lot BC and pr evious lots derived from simultaneous 30 samples measurements and analytical precision onboard R/V Mirai in May 2005. _________________________________________ Nitrate Phosphate Silicate CV% CV% CV% ------- --------- -------- BC 0.22 0.32 0.19 (AH) (0.39) (0.83) (0.13) (K) (0.3) (1.0) (0.2) Precision 0.22 0.22 0.12 _________________________________________ Note: N=30 x 2 Table 3.4.6: Homogeneity of lot BF and BG derived from simultaneous 7 samples measurements and analytical precision onboard R/V Mirai in May 2007. _________________________________________ Nitrate Phosphate Silicate CV% CV% CV% ------- --------- -------- BF 0.11 0.21 0.10 BG 0.14 0.17 0.08 Precision 0.05 0.07 0.06 _________________________________________ Note: N=7 x 4 (6.4) Comparability of RMNSs during the periods from 2003 to 2007 Cruise-to-cruise comparability has examined based on the results of the previous results of RMNSs measurements obtained among cruises, and RMNS international comparison experiments in 2003 and 2006. The uncertainties for each value were obtained similar method described in 7.1 in this chapter at the measurement before each cruise and inter-comparison study, shown as precruise and intercomparison, and mean of uncertainties during each cruise, only shown cruise code, respectively. As shown in Table 3.4.7, the nutrients concentrations of RMNSs were in good agreement among the measurements during the period from 2003 to 2007. For the silicate measurements, we show lot numbers and chemical company names of each cruise/measurement in the footnote. As shown in Table 3.4.7, there shows less comparability among the measurements due to less comparability among the standard solutions provided by chemical companies in the silicate measurements. Table 3.4.7(a): Comparability for nitrate. unit: µmol kg-1 RM Lots Cruise/Lab AH unc. BA unc. AY unc. AX unc. AV unc. BF unc. BC unc. ----- ---- ---- ---- ---- ---- ----- ---- ----- ---- ----- ---- ----- ---- NITRATE 2003 2003intercomparison 35.23 2005 MR05-01 35.54 0.08 0.05 0.03 21.49 0.09 33.38 0.08 MR05-02 0.07 0.02 5.61 0.02 21.45 0.07 33.35 0.06 40.70 0.06 MR05-05_1precruise 35.65 0.05 0.07 0.00 5.57 0.00 21.41 0.01 33.41 0.02 40.76 0.03 MR05-05_1 0.07 0.01 5.62 0.02 21.43 0.05 33.36 0.05 40.73 0.85 MR05-05_2 precruise 0.08 0.00 5.58 0.00 21.39 0.02 33.36 0.03 40.72 0.03 MR05-05_2 0.07 0.01 5.62 0.02 21.44 0.05 33.36 0.05 40.73 0.06 MR05-05_3 precruise 0.06 0.00 5.62 0.00 21.49 0.01 33.39 0.01 40.79 0.01 MR05-05_3 0.07 0.01 5.61 0.02 21.44 0.04 33.37 0.05 40.75 0.05 2006 MR06-02_precruise 5.62 0.00 33.36 0.01 MR06-03 precruise 5.59 0.00 33.42 0.02 MR06-03_2precruise 5.62 0.00 33.24 0.02 MR06-04_1precruise 5.60 0.01 33.33 0.04 MR06-04_2precruise 5.58 0.01 33.12 0.04 MR06-05_1precruise 0.07 0.00 5.61 0.00 21.42 0.01 33.28 0.01 40.63 0.02 2006intercomparison 0.04 0.00 5.58 0.01 21.40 0.02 33.32 0.03 40.63 0.04 2003intercomp_revisit 35.4 0.03 2007 MR07-01_precruise 0.04 0.00 5.59 0.01 21.38 0.04 33.31 0.06 40.60 0.07 MR07-02_precruise 0.04 0.00 5.62 0.01 21.44 0.02 33.40 0.03 41.36 0.04 MR07-04_precruise_1 35.74 0.03 0.07 0.00 5.67 0.00 21.59 0.02 33.49 0.03 41.47 0.03 40.83 0.03 MR07-04_precruise_2 35.80 0.01 0.08 0.00 5.65 0.00 21.60 0.01 33.47 0.01 41.55 0.02 40.92 0.02 MR07-04 0.08 0.01 5.61 0.02 21.41 0.06 33.38 0.05 41.36 0.06 40.77 0.05 MR07-05_precruise 0.08 0.00 5.65 0.01 21.43 0.02 33.44 0.04 41.46 0.05 40.87 0.04 MR07-06_1precruise 35.61 0.02 0.07 0.00 5.61 0.00 21.44 0.01 33.43 0.02 41.44 0.02 40.79 0.02 MR07-06_1 0.08 0.01 5.62 0.04 21.44 0.03 33.41 0.05 41.36 0.04 40.81 0.04 MR07-06_2precruise 35.61 0.04 0.06 0.00 5.62 0.01 21.43 0.02 33.54 0.04 41.42 0.05 40.79 0.05 MR07-06_2 0.08 0.01 5.61 0.02 21.44 0.03 33.39 0.06 41.36 0.05 40.81 0.04 Table 3.4.7(b:) Comparability for phosphate. unit: µmol kg-1 RM Lots Cruise/Lab AH unc. BA unc. AY unc. AX unc. AV unc. BF unc. BC unc. ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- PHOSPHATE 2003 2003intercomp 2.1 2005 MR05-01 2.133 0.023 0.065 0.006 1.622 0.008 2.52 0.007 MR05-02 0.061 0.010 0.515 0.009 1.614 0.008 2.515 0.008 2.778 0.010 MR05-05_1precruise 2.148 0.006 0.045 0.000 0.508 0.000 1.620 0.001 2.517 0.002 2.781 0.002 MR05-05_1 0.063 0.007 0.515 0.007 1.615 0.006 2.515 0.007 2.778 0.033 MR05-05_2 precruise 0.066 0.000 0.519 0.000 1.608 0.001 2.510 0.001 2.784 0.002 MR05-05_2 0.064 0.005 0.517 0.005 1.614 0.004 2.515 0.005 2.782 0.006 MR05-05_3 precruise 0.060 0.000 0.519 0.000 1.620 0.001 2.517 0.002 2.788 0.002 MR05-05_3 0.061 0.004 0.514 0.003 1.618 0.005 2.515 0.004 2.779 0.008 2006 MR06-02_precruise 0.516 0.000 2.515 0.002 MR06-03 precruise 0.496 0.001 2.499 0.003 MR06-03_2precruise 0.504 0.001 2.515 0.003 MR06-04_1precruise 0.502 0.000 2.501 0.002 MR06-04_2precruise 0.508 0.000 2.507 0.002 MR06-05_1precruise 0.071 0.000 0.527 0.000 1.629 0.000 2.523 0.001 2.788 0.001 2006intercomparison 0.071 0.000 0.524 0.000 1.623 0.001 2.515 0.002 2.791 0.002 2003intercomp_revisit 2.141 0.001 2007 MR07-01_precruise 0.073 0.000 0.524 0.001 1.620 0.002 2.521 0.003 2.784 0.003 MR07-02_precruise 0.080 0.000 0.593 0.000 1.646 0.001 2.553 0.002 2.832 0.002 MR07-04_precruise_1 2.140 0.002 0.062 0.000 0.518 0.000 1.620 0.001 2.512 0.002 2.811 0.002 2.782 0.002 MR07-04_precruise_2 2.146 0.002 0.056 0.000 0.514 0.000 1.620 0.001 2.517 0.002 2.811 0.002 2.788 0.002 MR07-04 0.066 0.004 0.521 0.005 1.617 0.005 2.513 0.004 2.805 0.006 2.781 0.007 MR07-05_precruise 0.052 0.000 0.506 0.001 1.618 0.002 2.508 0.003 2.804 0.003 2.794 0.003 MR07-06_1precruise 2.144 0.001 0.066 0.000 0.520 0.000 1.617 0.001 2.517 0.001 2.806 0.001 2.790 0.001 MR07-06_1 0.064 0.004 0.519 0.005 1.620 0.003 2.515 0.003 2.808 0.003 2.783 0.005 MR07-06_2precruise 2.146 0.002 0.067 0.000 0.520 0.000 1.620 0.001 2.517 0.002 2.808 0.002 2.789 0.002 MR07-06_2 0.066 0.004 0.521 0.005 1.619 0.005 2.515 0.003 2.807 0.004 2.785 0.006 Table 3.4.7(c): Comparability for silicate. unit: µmol kg-1 RM Lots Cruise/Lab AH unc. BA unc. AY unc. AX unc. AV unc. BF unc. BC unc. ----- ---- ---- ---- ---- ---- ----- ---- ----- ---- ----- ---- ----- ---- SILICATE 2003 2003intercomparison** 133.97 2005 MR05-01# 135.42 0.20 1.58 0.06 59.42 0.07 157.71 0.19 MR05-02# 1.65 0.05 30.15 0.08 59.53 0.11 157.87 0.19 159.93 0.19 MR05-05_1precruise## 135.89 0.13 1.55 0.00 30.13 0.02 59.55 0.03 157.92 0.09 160.05 0.09 MR05-05_1## 1.63 0.07 30.11 0.08 59.50 0.12 157.96 0.26 160.08 0.36 MR05-05_2 precruise## 1.62 0.00 30.12 0.02 59.46 0.04 158.02 0.09 160.22 0.10 MR05-05_2## 1.63 0.06 30.11 0.07 59.49 0.09 158.00 0.16 160.14 0.15 MR05-05_3 precruise## 1.61 0.00 30.13 0.03 59.54 0.05 158.02 0.14 160.12 0.14 MR05-05_3## 1.64 0.05 30.12 0.05 59.47 0.09 157.93 0.18 160.08 0.13 2006 MR06-02_precruise## 30.21 0.02 158.14 0.12 MR06-03 precruise† 29.39 0.02 154.47 0.10 MR06-03_2precruise† 29.56 0.01 154.52 0.08 MR06-04_1precruise† 29.50 0.00 154.31 0.02 MR06-04_2precruise† 29.44 0.01 153.98 0.03 MR06-05_1precruise*** 1.67 0.00 29,62 0.02 58.32 0.04 154.15 0.11 156.10 0.11 2006intercomparison† 1.64 0.00 29.50 0.01 58.18 0.03 154.33 0.08 156.31 0.08 2003intercomp_revisit† 132.55 0.07 2007 MR07-01_precruise† 1.59 0.00 29.37 0.03 57.99 0.06 154.21 0.15 156.06 0.16 MR07-02_precruise† 1.65 0.00 29.60 0.02 58.37 0.04 154.55 0.09 150.57 0.09 MR07-04_precruise_1 $ 133.38 0.06 1.61 0.00 29.57 0.01 58.46 0.03 154.82 0.07 151.03 0.07 156.98 0.07 MR07-04_precruise_2 $ 133.15 0.12 1.69 0.00 29.61 0.03 58.44 0.05 154.87 0.14 151.04 0.14 156.86 0.14 MR07-04 $ 1.62 0.07 29.42 0.07 58.11 0.11 154.45 0.21 150.59 0.16 156.62 0.48 MR07-05_precruise $ 1.70 0.00 29.43 0.02 58.08 0.04 154.05 0.11 150.48 0.11 156.31 0.11 MR07-06_1precruise $ 133.02 0.09 1.64 0.00 29.72 0.02 58.50 0.04 155.06 0.11 150.31 0.11 156.33 0.11 MR07-06_1 $ 1.61 0.04 29.43 0.07 58.13 0.08 154.48 0.13 150.53 0.11 156.64 0.08 MR07-06_2precruise $ 132.70 0.07 1.56 0.00 29.48 0.01 58.25 0.03 154.39 0.08 150.56 0.08 156.57 0.08 MR07-06_2 $ 1.58 0.07 29.35 0.08 58.04 0.10 154.38 0.16 150.49 0.13 156.61 0.13 List of lot numbers: *: Kanto 306F9235; **: Kanto 402F9041; #: Kanto 502F9205; ##: Kanto 609F9157; †: Merck OC551722; ***: Merck HC694149; $: Merck HC623465 (7) Quality control (7.1) Precision of nutrients analyses during the cruise MR0704 Precision of nutrients analyses during the cruise was evaluated based on the 11 measurements, which are measured every 12 samples, during a run at the concentration of C-6 std. We also evaluated the reproducibility based on the replicate analyses of five samples in each run. Summary of precisions are shown in Table 3.4.8. As shown in Table 3.4.8 and Figures 3.4.5-3.4.7, the precisions for each parameter are generally good considering the analytical precisions estimated from the simultaneous analyses of 12 samples in May 2007. Analytical precisions previously evaluated were 0.05% for nitrate, 0.07% for phosphate and 0.06% for silicate, respectively. During this cruise, analytical precisions were 0.06% for nitrate, 0.10% for phosphate and 0.07% for silicate in terms of median of precision, respectively. Then we can conclude that the analytical precisions for nitrate, phosphate and silicate were maintained throughout this cruise. The time series of precision are shown in Figures 3.4.5-3.4.7. Table 3.4.8: Summary of precision based on the replicate analyses of 11 samples in each run through out cruise. ______________________________________ Nitrate Phosphate Silicate CV% CV% CV% ------- --------- -------- Median 0.06 0.10 0.07 Mean 0.06 0.10 0.07 Maximum 0.12 0.19 0.12 Minimum 0.02 0.03 0.01 N 85 85 85 ______________________________________ Figure 3.4.5: Time series of precision of nitrate for MR0704. Figure 3.4.6: Time series of precision of phosphate for MR0704. Figure 3.4.7: Time series of precision of silicate for MR0704. MR0706 Precision of nutrients analyses during the cruise was evaluated based on the 11 measurements, which are measured every 12 samples, during a run at the concentration of C-6 std. We also evaluated the reproducibility based on the replicate analyses of five samples in each run. Summary of precisions are shown in Table 3.4.9. As shown in Table 3.4.9 and Figures 3.4.8-3.4.10, the precisions for each parameter are generally good considering the analytical precisions estimated from the simultaneous analyses of 12 samples in May 2007. Analytical precisions previously evaluated were 0.05% for nitrate, 0.07% for phosphate and 0.06% for silicate, respectively. During this cruise, analytical precisions were 0.07% for nitrate, 0.09% for phosphate and 0.07% for silicate in terms of median of precision, respectively. Then we can conclude that the analytical precisions for nitrate, phosphate and silicate were maintained throughout this cruise. The time series of precision are shown in Figures 3.4.8-3.4.10. Table 3.4.9: Summary of precision based on the replicate analyses of 11 samples in each run throughout cruise. ______________________________________ Nitrate Phosphate Silicate CV% CV% CV% ------- --------- -------- Median 0.07 0.09 0.07 Mean 0.07 0.10 0.07 Maximum 0.15 0.20 0.16 Minimum 0.02 0.03 0.02 N 266 266 266 ______________________________________ Figure 3.4.8: Time series of precision of nitrate for MR0706. Figure 3.4.9: Time series of precision of phosphate for MR0706. Figure 3.4.10: Time series of precision of silicate for MR0706. (7.2) Carry over We can also summarize the magnitudes of carry over throughout the cruise. These are small enough within acceptable levels as shown in Table 3.4.10. Table 3.4.10(a): Summary of carry over through out MR0704 cruise. ______________________________________ Nitrate Phosphate Silicate CV% CV% CV% ------- --------- -------- Median 0.16 0.11 0.20 Mean 0.16 0.13 0.20 Maximum 0.28 0.44 0.36 Minimum 0.02 0.00 0.07 N 85 85 85 ______________________________________ Table 3.4.10(b): Summary of carry over through out MR0706 cruise. ______________________________________ Nitrate Phosphate Silicate CV% CV% CV% ------- --------- -------- Median 0.14 0.14 0.12 Mean 0.14 0.14 0.13 Maximum 0.33 0.40 0.29 Minimum 0.00 0.00 0.01 N 266 266 266 ______________________________________ (8) Problems/improvements occurred and solutions. MR0704 During the analysis for the samples between station 8 and station 27 of WHP-P1, we got a problem on phosphate measurements.17 samples from 8 stations showed large difference on duplicate measurements exceeding uncertainty of 0.02 µmol kg-1. Especially 12 samples showed 0.05 to 0.97 µmol kg-1 higher values. We had judged that these higher values are contamination during the sampling from Niskin bottle or test tube itself. Therefore, we had checked probable source of this contamination including air-conditioners in the water sampling room and the laboratory. For the air-conditioners, we had cleaned up them. For the test tubes, we had made blank test for 440 tubes. We did not see any contaminations on test tubes. Since higher phosphate concentration did not occur after we clean up the air-conditioners, we had concluded that the source of the contamination of phosphate might be one of air-conditioners in the Lab. MR0706 No problem occurred during this cruise. REFERENCES Aminot, A. and Kerouel, R. 1991. Autoclaved seawater as a reference material for the determination of nitrate and phosphate in seawater. Anal. Chim. Acta, 248: 277-283. Aminot, A. and Kirkwood, D.S. 1995. Report on the results of the fifth ICES intercomparison exercise for nutrients in sea water, ICES coop. Res. Rep. Ser., 213. Aminot, A. and Kerouel, R. 1995. Reference material for nutrients in seawater: stability of nitrate, nitrite, ammonia and phosphate in autoclaved samples. Mar. Chem., 49: 221-232. Aoyama M., and Joyce T.M. 1996, WHP property comparisons from crossing lines in North Pacific. In Abstracts, 1996 WOCE Pacific Workshop, Newport Beach, California. Aoyama, M., Ota, H., Iwano, S., Kamiya, H., Kimura, M., Masuda, S., Nagai, N., Saito, K., Tubota, H. 2004. Reference material for nutrients in seawater in a seawater matrix, Mar. Chem., submitted. Aoyama, M., Susan B., Minhan, D., Hideshi, D., Louis, I. G., Kasai, H., Roger, K., Nurit, K., Doug, M., Murata, A., Nagai, N., Ogawa, H., Ota, H., Saito, H., Saito, K., Shimizu, T., Takano, H., Tsuda, A., Yokouchi, K., and Agnes, Y. 2007. Recent Comparability of Oceanographic Nutrients Data: Results of a 2003 Intercomparison Exercise Using Reference Materials. Analytical Sciences, 23: 1151-1154. Grasshoff, K., Ehrhardt, M., Kremling K. et al. 1983. Methods of seawater anylysis. 2nd rev. Weinheim: Verlag Chemie, Germany, West. Uchida, H. & Fukasawa, M. WHP P6, A10, I3/I4 REVISIT DATA BOOK Blue Earth Global Expedition 2003 1, 2, (Aiwa Printing Co., Ltd., Tokyo, 2005). Joyce, T. and Corry, C. 1994. Requirements for WOCE hydrographic programmed data reporting. WHPO Publication, 90-1, Revision 2, WOCE Report No. 67/91. Kirkwood, D.S. 1992. Stability of solutions of nutrient salts during storage. Mar. Chem., 38 : 151-164. Kirkwood, D.S. Aminot, A. and Perttila, M. 1991. Report on the results of the ICES fourth intercomparison exercise for nutrients in sea water. ICES coop. Res. Rep. Ser., 174. Mordy, C.W., Aoyama, M., Gordon, L.I., Johnson, G.C., Key, R.M., Ross, A.A., Jennings, J.C. and Wilson. J. 2000. Deep water comparison studies of the Pacific WOCE nutrient data set. Eos Trans-American Geophysical Union. 80 (supplement), OS43. Murphy, J., and Riley, J.P. 1962. Analytica chim. Acta 27, 31-36. Gouretski, V.V. and Jancke, K. 2001. Systematic errors as the cause for an apparent deep water property variability: global analysis of the WOCE and historical hydrographic data••REVIEW ARTICLE, Progress In Oceanography, 48: Issue 4, 337-402. 3.5. Dissolved inorganic carbon (CT) 9 November 2008 (1) Personnel Akihiko Murata (IORGC/JAMSTEC) Yoshiko Ishikawa (MWJ) Yasuhiro Arii (MWJ) Mikio Kitada (MWJ) (2) Objectives Concentrations of CO2 in the atmosphere are now increasing at a rate of 1.5 ppmv y-1 due to human activities such as burning of fossil fuels, deforestation, cement production, etc. It is an urgent task to estimate as accurately as possible the absorption capacity of the oceans against the increased atmospheric CO2, and to clarify the mechanism of the CO2 absorption, because the magnitude of the predicted global warming depends on the levels of CO2 in the atmosphere, and because the ocean currently absorbs 1/3 of the 6 Gt of carbon emitted into the atmosphere each year by human activities. In the cruises (MR07-04 and MR07-06, revisit of WOCE P1 and P14 lines) using the R/V Mirai, we were aimed at quantifying how much anthropogenic CO2 is absorbed in the Pacific Ocean. For the purpose, we measured CO2-system properties such as dissolved inorganic carbon (CT), total alkalinity (AT), pH and underway pCO2. In this section, we describe data on CT obtained in the cruise in detail. (3) Apparatus Measurements of CT were made with two total CO2 measuring systems (systems-A and -C; Nippon ANS, Inc.), which are slightly different from each other. The systems comprise of a seawater dispensing system, a CO2 extraction system and a coulometer (Model 5012, UIC Inc.). The seawater dispensing system has an auto-sampler (6 ports), which takes seawater from a 300 ml borosilicate glass bottle and dispenses the seawater to a pipette of nominal 20 or 26 ml volume by a PC control. The pipette is kept at 20°C by a water jacket, where water from a water bath set at 20°C is circulated. CO2 dissolved in a seawater sample is extracted in a stripping chamber of a CO2 extraction system by adding phosphoric acid (10% v/v). The stripping chamber is approx. 25 cm long and has a fine frit at the bottom. The acid is added to the stripping chamber from the bottom of the chamber by pressurizing an acid bottle for a given time to push out a right amount of acid. The pressurizing is made with nitrogen gas (99.9999%). After the acid is transferred to the stripping chamber, a seawater sample kept in a pipette is introduced to the stripping chamber by the same method as in adding an acid. The seawater reacted with phosphoric acid is stripped of CO2 by bubbling the nitrogen gas through a fine frit at the bottom of the stripping chamber. The CO2 stripped in the stripping chamber is carried by the nitrogen gas (140 ml min-1 for the systems-A and -C) to the coulometer through a dehydrating module. For the system-A, the module consists of two electric dehumidifiers (kept at 1 - 2°C) and a chemical desiccant (Mg(ClO4)2). For the system-C, it consists of three electric dehumidifiers with a chemical desiccant. (4) Shipboard measurement (4.1) Sampling All seawater samples were collected from depth with 12 liter Niskin bottles basically at every other stations. The seawater samples for CT were taken with a plastic drawing tube (PFA tubing connected to silicone rubber tubing) into a 300 ml borosilicate glass bottle. The glass bottle was filled with seawater smoothly from the bottom following a rinse with a seawater of 2 full, bottle volumes. The glass bottle was closed by a stopper, which was fitted to the bottle mouth gravimetrically without additional force. At a chemical laboratory on the ship, a headspace of approx. 1% of the bottle volume was made by removing seawater with a plastic pipette. A saturated mercuric chloride of 100 µl was added to poison seawater samples. The glass bottles were sealed with a greased (Apiezon M, M&I Materials Ltd) ground glass stopper and the clips were secured. The seawater samples were kept at 4°C in a refrigerator until analysis. A few hours just before analysis, the seawater samples were kept at 20°C in a water bath. (4.2) Analysis At the start of each leg, we calibrated the measuring systems by blank and 5 kinds of Na2CO3 solutions (nominally 500, 1000 1500, 2000, 2500 µmol/L). As it was empirically known that coulometers do not show a stable signal (low repeatability) with fresh (low absorption of carbon) coulometer solutions. Therefore we measured 2% CO2 gas repeatedly until the measurements became stable. Then we started the calibration. The measurement sequence such as system blank (phosphoric acid blank), 2% CO2 gas in a nitrogen base, and seawater samples (6)was programmed to repeat. The measurement of 2% CO2 gas was made to monitor response of coulometer solutions (from UIC, Inc.). For every renewal of coulometer solutions, certified reference materials (CRMs, batch 80 and a small number of batch 75) provided by Prof. A. G. Dickson of Scripps Institution of Oceanography were analyzed. In addition, in-house reference materials (RM) (batch: QRM Q15, Q16 and Q17) were measured at the initial, intermediate and end times of a coulometer solution's lifetime. The preliminary values were reported in a data sheet on the ship. Repeatability and vertical profiles of CT based on raw data for each station helped us check performances of the measuring systems. In the cruise, we finished all the analyses for CT on board the ship. As we used two systems, we had not encountered such a situation as we had to abandon the measurement due to time limitation. (5) Quality control We conducted quality control of the data after return to a laboratory on land. With calibration factors, which had been determined on board a ship based on blank and 5 kinds of Na2CO3 solutions, we calculated CT of CRM (batches 80 and 75), and plotted the values as a function of sequential day, separating legs and the systems used. There were no statistically-significant trends of CRM measurements. Based on the averages of CT of CRM, we re-calculated the calibration factors so that measurements of seawater samples become traceable to the certified value of batch 80. We did not use the measured results of batch 75 because of a small number of measurements. Temporal variations of RM measurements for one coulomer solution are shown in Fig. 3.5.1. From this figure, it is evident that RM measurements had a linear trend of ~3 to ~7 µmol kg-1, implying that measurements of seawater samples also have the trend. The trend was also found in temporal changes of 2% CO2 gas measurements. The trend seems to be due to "cell age" change (Johnson et al., 1998) of a coulometer solution. Considering the trends, we adjusted measurements of seawater samples so as to be traceable to the certified value (2006.50 µmol kg-1) of batch 80. Finally we surveyed vertical profiles of CT. In particular, we examined whether systematic differences between measurements of the systems-A and -C existed or not. Then taking otherinformation of analyses into account, we determined a flag of each value of CT. The average and standard deviation of absolute values of differences of CT analyzed consecutively were 1.1 and 1.0 µmol kg-1 (n=162), 1.2 and 1.1 µmol kg- 1 (n = 440) for MR07-04 and MR07-06, respectively. To evaluate accuracy of measured CT, we compared vertical profiles of CT measured in MR07-04 and MR07-06 with those measured at a station of other WOCE lines crossing the P1 and P14 lines. Results are shown in Fig. 3.5.2. From these figures, it is found that CT measured in the cruises is sufficiently accurate. Together with other comparisons, we estimated the accuracy to be ~ ± 2.0 µmol kg-1. REFERENCE Johnson, K. M., A. G. Dickson, G. Eischeid, C. Goyet, P. Guenther, R. M. Key, F. J. Millero, D. Purkerson, C. L. Sabine, R. G. Schottle, D. W. R. Wallace, R. J. Wilke and C. D. Winn (1998), Coulometric total carbon dioxide analysis for marine studies: assessment of the quality of total inorganic carbon measurements made during the US Indian Ocean CO2 survey 1994-1996, Mar. Chem., 63, 21-37. Fig. 3.5.1: Distributions of RM measurements as a function of seaquential day for Stns. 044 and 046 during MR07-06. Fig. 3.5.2: Comparison of vertical profiles of CT measured in MR07-04 with those measured previously at the cross points with (a) P16, (b) P17 and (c) P15 lines of WOCE. 3.6. Total alkalinity (AT) 9 November 2008 (1) Personnel Akihiko Murata (IORGC/JAMSTEC) Minoru Kamata (MWJ) Fuyuki Shibata (MWJ) Aya Hatsuyama (MWJ) (2) Objectives Concentrations of CO2 in the atmosphere are now increasing at a rate of 1.5 ppmv y-1 due to human activities such as burning of fossil fuels, deforestation, cement production, etc. It is an urgent task to estimate as accurately as possible the absorption capacity of the oceans against the increased atmospheric CO2, and to clarify the mechanism of the CO2 absorption, because the magnitude of the predicted global warming depends on the levels of CO2 in the atmosphere, and because the ocean currently absorbs 1/3 of the 6 Gt of carbon emitted into the atmosphere each year by human activities. In the cruises (MR07-04 and MR07-06, revisit of WOCE P1 and P14 lines) using the R/V Mirai, we were aimed at quantifying how much anthropogenic CO2 is absorbed in the Pacific Ocean. For the purpose, we measured CO2-system properties such as dissolved inorganic carbon (CT), total alkalinity (AT), pH and underway pCO2. In this section, we describe data on AT obtained in the cruise in detail. (3) Apparatus Measurement of AT was made based on spectrophotometry using a custom-made system (Nippon ANS, Inc.). The system comprises of a water dispensing unit, an auto-burette (765 Dosimat, Metrohm), and a spectrophotometer (Carry 50 Bio, Varian), which are automatically controlled by a PC. The water dispensing unit has a water-jacketed pipette and a water-jacketed titration cell. The spectrophotometer has a water-jacketed quartz cell, length and volume of which are 8 cm and 13 ml, respectively. To circulate sample seawater between the titration and the qaurtz cells, PFA tubes are connected to the cells. A seawater of approx. 40 ml is transferred from a sample bottle (brosilicate glass bottle; 130 ml) into the water-jacketed (25°C) pipette by pressurizing the sample bottle (nitrogen gas), and is introduced into the water-jacketed (25 ºC) titration cell. The seawater is circulated between the titration and the quartz cells by a peristaric pump to rinse the route. Then, Milli-Q water is introduced into the titration cell, and is circulated in the same route twice to rinse the route. Next, a seawater of approx. 40 ml is weighted again by the pipette, and is transferred into the titration cell. The weighted seawater is introduced into the quartz cell. Then, for seawater blank, absorbances are measured at three wavelengts (750, 616 and 444 nm). After the measurement, an acid titrant, which is a mixture of approx. 0.05 M HCl in 0.65 M NaCl and bromocresol green (BCG) is added (approx. 2.1 ml) into the titration cell. The seawater + acid titrant solution is circulated for 6 minutes between the titration and the quartz cells, with stirring by a stirring tip and bubbling by wet nitrogen gas in the titration cell. Then, absorbances at the three wavelengths are measured again. Calculation of AT was made by the following equation: A = (-[H+] V + M V ) / V T T SA A A S, where MA is the molarity of the acid titrant added to the seawater sample, [H+]T is the total excess hydrogen ion concentration in the seawater, and VS, VA and VSA are the initial seawater volume, the added acid titrant volume, and the combined seawater plus acid titrant volume, respectively. [H+]T is calculated from the measured absorbances based on the following equation (Yao and Byrne, 1998): pHT = -log[H+]T = 4.2699+0.002578(35-S)+log((R-0.00131)/(2.3148-0.1299R))- log(1-0.001005S), where S is the sample salinity, and R is the absorbance ratio calculated as: R = (A - A ) / (A - A ), 616 750 444 750 where Ai is the absorbance at wavelength i nm. The HCl in the acid titrant was standardized (0.049977 M) on land. The concentrations of BCG were estimated to be approx. 0.04 x 10-3 M, and 2.0 x 10-6 M in the acid titrant and in the sample seawater, respectively. (4) Shipboard measurement (4.1) Sampling All seawater samples were collected from depth using 12 liter Niskin bottles basically at every other stations. The seawater samples for AT were taken with a plastic drawing tube (PFA tubing connected to silicone rubber tubing) into borosilicate glass bottles of 130 ml. The glass bottle was filled with seawater smoothly from the bottom after rinsing it with a seawater of half a or a full bottle volume. A few hours before analysis, the seawater samples were kept at 25°C in a water bath. (4.2) Analysis We analyzed reference materials (RM; Batch: QRM 15, 16 and 17), which were produced for CT measurement by JAMSTEC, but were efficient also for the monitor of AT measurement. In addition, certified reference materials (CRM, batches 80 and 75, certified value = 2214.49 and 2210.09 µmol kg-1, respectively) were also analyzed periodically to monitor systematic differences of measured AT. The reported values of AT were set to be traceable to the certified value (2214.49 µmol kg-1) of the batch 80. The preliminary values were reported in a data sheet on the ship. Repeatability calculated from replicate samples and vertical profiles of AT based on raw data for each station helped us check performance of the measuring system. In the cruise, we finished all the analyses for AT on board the ship. We did not encounter so serious problems as we had to give up the analyses. (5) Quality control Temporal changes of AT were monitored by measuring AT of CRM. We found no abnormal measurements during the cruises. After making the measured values of AT comparable to CRM, we examined vertical profiles of AT. Then taking other information of analyses into account, we determined a flag of each value of AT. The average and standard deviation of absolute values of differences of AT analyzed consecutively were 0.4 and 0.4 µmol kg-1 (n = 152), and 0.5 and 0.5 µmol kg-1 (n = 407) for MR07-04 and MR07-06, respectively. To evaluate accuracy of measured AT, we compared vertical profiles of AT measured in MR07-04 and MR07-06 with those measured at a station of other WOCE lines crossing the P1 and P14 lines. Results are shown in Fig. 3.6.1. From these figures, it is found that AT measured in the cruises are more accurate than those obtained in other WOCE lines, which were measured based on potentionmetry. Together with other comparison, we estimated that the reported values were systematically 2.0 -3.0 µmol kg-1 higher than the previously reported values. REFERENCE Yao W. and R. H. Byrne (1998) Simplified seawater alkalinity analysis: Use of linear array spectrometers. Deep-Sea Research I 45, 1383-1392. Fig. 3.6.1: Comparison of vertical profiles of AT measured in MR07-04 and MR07- 6 with those measured previously at the cross points with (a) P16, (b) P17 (c) P15, and (d) P2 lines of WOCE. 3.7. pH 9 November 2008 (1) Personnel Akihiko Murata (IORGC, JAMSTEC) Fuyuki Shibata (MWJ) Aya Hatsuyama (MWJ) (2) Objectives Concentrations of CO2 in the atmosphere are now increasing at a rate of 1.5 ppmv y-1 due to human activities such as burning of fossil fuels, deforestation, cement production, etc. It is an urgent task to estimate as accurately as possible the absorption capacity of the oceans against the increased atmospheric CO2, and to clarify the mechanism of the CO2 absorption, because the magnitude of the anticipated global warming depends on the levels of CO2 in the atmosphere, and because the ocean currently absorbs 1/3 of the 6 Gt of carbon emitted into the atmosphere each year by human activities. In the cruises (MR07-04 and MR07-06, revisit of WOCE P1 and P14 lines) using the R/V Mirai, we were aimed at quantifying how much anthropogenic CO2 is absorbed in the Pacific Ocean. For the purpose, we measured CO2-system properties such as dissolved inorganic carbon (CT), total alkalinity (AT), pH and underway pCO2. In this section, we describe data on pH obtained in the cruise in detail. (3) Apparatus Measurement of pH was made by a pH measuring system (Nippon ANS, Inc.), which adopts spectrophotometry. The system comprises of a water dispensing unit and a spectrophotometer (Carry 50 Scan, Varian). Seawater is transferred from borosilicate glass bottle (300 ml) to a sample cell in the spectrophotometer. The length and volume of the cell are 8 cm and 13 ml, respectively, and the sample cell was kept at 25.00 ± 0.05°C in a thermostated compartment. First, absorbances of seawater only are measured at three wavelengths (730, 578 and 434 nm). Then an indicator is injected and circulated for about 4 minutes. to mix the indicator and seawater sufficiently. After the pump is stopped, the absorbances of seawater + indicator are measured at the same wavelengths. The pH is calculated based on the following equation (Clayton and Byrne, 1993): ⎛ A1/A2 - 0.00691 ⎞ pH = pK2 + log ⎜ -------------------- ⎟ (1), ⎝ 2.2220-0.1331(A1/A2) ⎠ where A1 and A2 indicate absorbances at 578 and 434 nm, respectively, and pK2 is calculated as a function of water temperature and salinity. (4) Shipboard measurement (4.1) Sampling All seawater samples were collected from depth with 12 liter Niskin bottles basically at every other stations. The seawater samples for pH were taken with a plastic drawing tube (PFA tubing connected to silicone rubber tubing) into a 300 ml borosilicate glass bottle, which was the same as used for CT sampling. The glass bottle was filled with seawater smoothly from the bottom following a rinse with a sea water of 2 full, bottle volumes. The glass bottle was closed by a stopper, which was fitted to the bottle mouth gravimetrically without additional force. A few hours just before analysis, the seawater samples were kept at 25°C in a water bath. (4.2) Analysis For an indicator solution, m-cresol purple (2 mM) was used. The indicator solution was produced on board a ship, and retained in a 1000 ml DURAN(r) laboratory bottle. We renewed an indicator solution 3 times when the headspace of the bottle became large, and monitored pH or absorbance ratio of the indicator solution by another spectrophotometer (Carry 50 Scan, Varian) using a cell with a short path length of 0.5 mm. In most indicator solutions, the absorbance ratios of the indicator solution were initially in the range 1.4 - 1.6, and decreased to 1.1. It is difficult to mix seawater with an indicator solution sufficiently under no headspace condition. However, by circulating the mixed solution with a peristaltic pump, a well-mixed condition came to be attained rather shortly, leading to a rapid stabilization of absorbance. We renewed a TYGON(r) tube of a peristaltic pump periodically, when a tube deteriorated. Absorbances of seawater only and seawater + indicator solutions were measured 15 times each, and averages computed from the last five values of absorbance were used for the calculation of pH (Eq. 1). The preliminary values of pH were reported in a data sheet on the ship. Repeatability calculated from replicate samples and vertical profiles of pH based on raw data for each station helped us check performance of the measuring system. We finished all the analyses for pH on board the ship. We did not encounter so serious a problem as we had to give up the analyses. However, we sometimes experienced malfunctions of the system during the cruise: Differences between absorbances of seawater only and those of seawater + indicator solution were infrequently greater than ± 0.001. This implies dirt of the cell. In this case, we cleaned or replaced the cell. (5) Quality control It is recommended that correction for pH change resulting from addition of indicator solutions is made (DOE, 1994). To check the perturbation of pH due to the addition, we measured absorbance ratios by doubling the volume of indicator solutions added to a same seawater sample. We corrected absorbance ratios based on an empirical method (DOE, 1994), although the perturbations were small. Figure 3.7.1 illustrates an example of perturbation of absorbance ratios by adding indicator solutions. We surveyed vertical profiles of pH. In particular, we examined whether systematic differences between before and after the renewal of indicator solutions existed or not. Then taking other information of analyses into account, we determined a flag of each value of pH. The average and standard deviation of absolute values of differences of pH analyzed consecutively were 0.0008 and 0.0007 pH unit (n = 199), and 0.0005 and 0.0006 pH unit (n = 565) for MR07-04 and MR07-06, respectively. REFERENCES Clayton T.D. & R.H. Byrne (1993) Spectrophotometric seawater pH measurements: total hydrogen ion concentration scale calibration of m-cresol purple and at- sea results. Deep-Sea Research 40, 2115-2129. DOE (1994) Handbook of methods for the analysis of the various parameters of the carbon dioxide system in sea water, version 2, A. G. Dickson & C. Goyet, eds. (unpublished manuscript). Figure 3.7.1: Perturbation of absorbance ratios by adding indicator solutions. The line (y = -0.00009x + 0.00011, R2 = 0.72132) was determined by the method of least squares. 3.8 Chlorofluorocarbons (CFCs) 3 November 2008 (1) Personnel Ken'ichi Sas aki (MIO, JAMSTEC) Masah ide Wakita (MIO, JAMSTEC) Katsunori Sagishima (MWJ) Yuichi Sonoyama (MWJ) Shok o Tatam isashi (MWJ) (2) Introduction Chlorofluorocarbons (CFCs) are completely man-made compounds that are chemically and biologically stable gasses in the environment. The CFCs have accumulated in the atmosphere since 1930's (Walker et al., 2000) and the atmospheric CFCs can slightly dissolve in sea surface water. The dissolved CFCs concentrations in sea surface water should have changed year by year and then penetrate into the ocean interior by water circulation. Three chemical species of CFCs, namely CFC-11 (CCl3F), CFC-12 (CCl2F2) and CFC-113 (C2Cl3F3), dissolved in seawater are useful transient tracers for the ocean circulation with times scale on the order of decades. In these cruises, we determined concentrations of CFCs dissolved in seawater on board. Carbon tetrachloride (CCl4), CFC like compound, have been used as an additional chemical tracer which have longer history than CFCs. This compound was also been analyzed for several stations as qualitative indicator. (3) Apparatus Dissolved CFCs and CCl4 were measured by a typical method modified from the original design of Bullister and Weiss (1988). A custom made purging and trapping system was attached to gas chromatograph (GC-14B: Shimadzu Ltd) having an electron capture detector (ECD-14: Shimadzu Ltd). Cold trap columns were stainless steel tube packed with 80/100 mesh Porapak T in MR07-04 cruise and with 80/100 mesh Porapak N in MR07-06 cruise. A pre-column and a main column on CFCs system were Silica Plot capillary column [i.d.: 0.53mm, length: 8m, film thickness: 6µm] and a complex capillary column (Pola Bond-Q [i.d.: 0.53mm, length: 7m, film thickness: 10µm] followed by Silica Plot [i. d.: 0.53mm, length: 22m, film thickness: 6µm]), respectively. On the CCl4 system, these were DB-624 capillary column [i.d.: 0.53 mm, length: 30 m, film thickness: 3µm] and longer DB-624 capillary column [length: 100 m], respectively. (4) Shipboard measurement (4.1) Sampling Before casting CTD, the water sampling system was cleaned by diluted acetone to remove any oils which could cause contaminations of CFCs. Seawater sub-samples were collected from 12 litter Niskin bottles into glass bottles. The bottle volumes were 300ml and 150ml for CFCs and CCl4 analyses, respectively. The bottles had been filled with pure nitrogen gas before the sampling. The two times bottle volumes of seawater sample were overflowed. The bottles filled with seawater were kept in water bathes roughly controlled on the sample temperature. The concentrations were determined as soon as possible (normally within 12 hrs). (4.2) Analysis Constant volume of sample water (50ml for CFCs and 30 ml for CCl4) was taken into the purging & trapping system. Dissolved CFCs and CCl4 were extracted by nitrogen gas purge. The sample gas were dried by magnesium perchlorate desiccant and concentrated on a trap column cooled to -45°C. The compounds were desorbed by electrically heating the trap column to 140°C for CFCs and to 130°C for CCl4 within 1.5 minutes, and led into the pre-column. The gasses were roughly separated on the pre-column. When required compounds were eluted, the pre-column was switched onto cleaning line and flushed back by counter flow of pure nitrogen gas. The back flush system prevented to enter any compounds that had higher retention time than CFCs and CCl4 into main analytical column and permitted short time analysis. The compounds which were sent onto main column were separated further and detected by an electron capture detector (ECD). On the CFCs analytical system, retention time of compounds was around 1.5, 4.4 and 11 minutes for CFC-12, -11 and -113, respectively. On the CCl4 system, that was 6 min, 8min, 10 min and 15 min for CFC-12, -11, -113, and CCl4. Temperatures of an analytical column and a detector were 95 and 240°C for CFC analysis, respectively. These were 50 and 200°C for CCl4 analysis, respectively. Pure nitrogen gas (99.99995) was purified by a molecular sieve 13X gas filter and was used for analyses. On the CFCs system, mass flow rates of nitrogen gas were 17, 20, 20 and 200 ml/min for carrier, detector make up, back flush and sample purging gasses, respectively. On the CCl4 system, these were 13, 27, 20 and 130 ml/min, respectively. Gas loops whose volumes were around 1, 3 and 10 ml were used for introducing standard gases into the analytical system. The standard gasses had been made by Japan Fine Products co. ltd. Standard gas cylinder numbers used in cruises were listed in Table 3-8-1. Cylinder of CPB30524 was for reference. Precise mixing ratios of the standard gasses were calculated by gravimetric data. The standard gases used in this cruise have not been calibrated to SIO scale standard gases yet because SIO scale standard gasses is hard to obtain due to legal difficulties for CFCs import into Japan. The data will be corrected as soon as possible when we obtain the standard gasses. Table 3-8-1. Standard gas cylinder list. _______________________________________________ Concentration determined gravi- metric data (pptv). ------------------------------- Cylinder No. CFC-11 CFC-12 CFC-113 CCl4 ------------ ------ ------ ------- ---- CPB02957 300 159 30.0 249 CPB03033 302 162 30.8 0 CPB03322 301 161 30.6 399 CPB09898 301 161 30.6 400 CPB28489 300 160 30.0 250 CPB30524 300 159 30.2 403 _______________________________________________ (5) Quality control (5.1) Main problems on the shipboard analysis CFC-12 CFC-12 data observed from Station P01-010 and P01-011 (MR07-04) may contain large err. At the analyses, there was trouble of air conditioner of analytical room and room temperature remarkably rose up to 37°C. Capacity of cooling system of cold trap felled off and a part of CFC-12 was not quantitatively absorbed on the trap. Although the concentrations were corrected by the trapping efficiency estimated from standard gas analyses, we give this data flag "3". CFC-113 A large and broad peak was interfered determining CFC-113 peak area for samples collected from surface several hundred meters depth in the latitude band of subtropical and tropical region (MR07-06). Retention time of the interfering peak was around 3% shorter than that of CFC-113. The peak of a compound interfering CFC-113 determination could not be completely separated from the peak of CFC-113 by our analytical condition. We tried to split these peaks on chromatogram analysis and give flag "4". In the case of the interfering peak completely covering the CFC-113 peak, we could not determine CFC-113 peak area and give flag "5". CCl4 Several problems were found in CCl analysis as follows, and all CCl data were given flag "4". One of the problems was in standardization. Mixing ratio of the atmospheric CCl 4 observed in these cruises was notably higher than the annual mean value reported by Dr. J. L. Bullister in web site of Carbon Dioxide Information Analysis Center (CDIAC,http://cdiac.ornl.gov/oceans/new_atmCFC.html). Concentration of CCl4 in surface water was also higher than predicted value from the solubility (Bullister and Wisegarver, 1998). Concentration of CCl4 was corrected by using the reported atmospheric CCl4 mixing ratio and concentration of CCl4 was corrected but accuracy was doubtful. Additional problem was high blank. The gas line blank was negligible but water line blank was high and varied from 0.04 to 0.07 pmol/kg. These blank values were too high to determine precise concentration of CCl4 though the blank value was frequently obtained and corrected. (5.2) Blank of CFC-11 and CFC-12 Some blank water samples which were made by nitrogen purge of seawater in CFCs sample bottle were analyzed and any CFCs were not detected. Significant increase in CFCs concentration during keeping sampling bottle in a water bath was not found for around one week. CFCs concentrations in deep water which was one of oldest water masses in the ocean were low but not zero for CFC-11 and - 12. Average concentrations of CFC-11, 12 in the deep water denser than 27.7 σθ and warmer than 1°C of potential temperature were 0.012 ± 0.005, 0.006 ± 0.003 pmol kg-1(n > 1500), respectively. These values were assumed as sampling blanks which was contaminations from Niskin bottle and/or during sub-sampling and were subtracted from all data. Significant blank was not found in CFC-113 measurements. (5.3) Precisions The analytical precisions were estimated from replicate sample analyses (Table 3-8-2). The replicate samples were basically collected from two sampling depths which is around 150 m and 700 m depths. Table 3-8-2: Analytical precisions of CFC concentrations estimated from replicate analyses. ________________________________________ Precisions* Cruise CFCs (pmol kg-1) (%) n ------- ------- ----------- --- --- MR07-04 CFC-11 0.009 0.4 154 CFC-12 0.007 0.6 151 CFC-113 0.008 7 158 MR07-06 Leg 1 CFC-11 0.010 0.6 233 CFC-12 0.008 0.9 234 CFC-113 0.008 10 217 MR07-06 Leg 2 CFC-11 0.007 0.6 206 CFC-12 0.009 0.8 206 CFC-113 0.004 5 112 ________________________________________ *Precision whichever is greater (6) REFERENCES Walker, S.J., Weiss, R.F. and Salameh, P.K., Reconstructed histories of the annual mean atmospheric mole fractions for the halocarbons CFC-11, CFC-12, CFC- 113 and Carbon Tetrachloride, Journal of Geophysical Research, 105, 14,285- 14,296, (2000). Bullister, J.L and Weiss, R.F. Determination of CCl3F and CCl2F2 in seawater and air. Deep Sea Research, 35, 839-853 (1988). 3.9 Lowered Acoustic Doppler Current Profiler 5 November 2008 (1) Personnel Shinya Kouketsu (JAMSTEC) Hiroshi Uchida (JAMSTEC) Yoshimi Kawai (JAMSTEC) Katsurou Katsumata (JAMSTEC) Toshimasa Doi (JAMSTEC) (2) Overview of the equipment An acoustic Doppler current profiler (ADCP) was integrated with the CTD/RMS package. The lowered ADCP (LADCP), Workhorse Monitor WHM300 (Teledyne RD Instruments, San Diego, California, USA), which has 4 downward facing transducers with 20-degree beam angles, rated to 6000 m. The LADCP makes direct current measurements at the depth of the CTD, thus providing a full profile of velocity. The LADCP was powered during the CTD casts by a 50.4 voltsrechargeable Ni-Cd battery pack. The LADCP unit was set for recording internally prior to each cast. After each cast the internally stored observed data was uploaded to the computer on-board. By combining the measured velocity of the sea water and bottom with respect to the instrument, and shipboard navigation data during the CTD cast, the absolute velocity profile can be obtained (e.g. Visbeck, 2002). The instrument used in this cruise was as follows. Teledyne RD Instruments, WHM300-I-UG27 S/N 8484 (CPU firmware ver. 16.28) S/N 2553 (CPU firmware ver. 16.28) (with pressure sensor) * * Serial number 2553 was used at stations from P14C_41 to P14C_32. (3) Data collection In this cruise, data were collected with the following configuration. Bin size: 8.0 m Number of bins: 14 Pings per ensemble: 1 Ping interval: 1.0 sec At the following stations, the CTD cast was carried out without the LADCP, because the maximum pressure was beyond the pressure-proof of the LADCP (6000 m). Stations from P01_11 to P01_12 Stations from P01_44 to P01_46 Stations from P01_53 to P01_54 Stations from P14N_24 to P14N_23 (4) Data collection problems Echo intensity of a transducer of serial number 8484 was found to become weak gradually, which is shown in the echo intensity means in each cast at the second (Fig. 3.8.1). The peak after station P14N_140 results from enhanced reflections by the equatorial upwelling and that after P14C-52 from the substitution by anther sensor (serial number 2553). A part of data from the substituted sensor was missed by unknown reason at the following stations. P14C_40: from 2920 m of down-cast to 2870 m of up-cast P14C_33: from 2440 m of down-cast to 2680 m of up-cast P14C_32: from 3540 m of down-cast to 3330 m of up-cast Therefore the original sensor (serial number 8484) was used again after 10 casts from the substitution. Fig. 3.9.1: Cast-averaged echo intensity at the second bin in each beam of the LADCP for MR07-04 and MR07-06 cruises. (4) Data process Vertical profiles of velocity are obtained by the inversion method (Visbeck, 2002). Since the first bin from LADCP is influenced by the turbulence generated by CTD frame, the weight for the inversion is set to small value of 0.1. GPS navigation data are used in the calculation of the reference velocities and the bottom-track data are used for the correction of reference velocities. Shipboard ADCP (SADCP) data averaged for 1 minute are also included in the calculation. The CTD data are used for the sound speed and depth calculation. IGRF (International Geomagnetic Reference Field) 10th generation data are used for calculating magnetic deviation to correct the direction of velocity. In the processing, we use Matlab routines provided from M. Visbeck and G. Krahmann (http://ladcp.ldeo.columbia.edu/ladcp). REFERENCE Visbeck, M. (2002): Deep velocity profiling using Lowered Acoustic Doppler Current Profilers: Bottom track and inverse solutions. J. Atmos. Oceanic Technol., 19, 794-807. 3.10 δ13C and ∆14C of Dissolved Inorganic Carbon 14 June 2013 Yuichiro Kumamoto, Research Institute for Global Change, JAMSTEC (1) Personnel Yuichiro Kumamoto (Research Institute for Global Change, JAMSTEC) (2) Introduction Stable and radioactive carbon isotopic ratios (δ13C and ∆14C) of dissolved inorganic carbon (DIC) are good tracers for the anthropogenic carbon in the ocean. During our MR07-04 and MR07-06 cruises in 2007, named revisit cruises of WHP-P01 (47°N approx.) and WHP-P14NC (179°E approx.) lines, respectively, we collected seawater samples for δ13C and ∆14C analyses at stations along the lines in the Pacific. Here we report the final results of δ13C and ∆14C of DIC. Our preliminary report of δ13C and ∆14C measurements is replaced by this final report. General information and other hydrographic data of the cruises have already published in our data book for WHP-P01 and -P14NC Revisit Cruises (Kawano et al., 2009) Figure 3.10.1: Sampling stations for δ13C and ∆14C of dissolved inorganic carbon during MR07-04 and MRO7-06 cruises (July 2007 - December 2007) except stations P01-010, P01-027, P01-060, P01-072, and P01-097. (3) Sample collection The sampling stations are summarized in Figure 3.10.1 and Table 3.10.1. A total of 1319 seawater samples, including 74 replicate samples, were collected between surface (about 10 m depth) and near bottom at 39 stations using 12-liter X-Niskin bottles. The seawater in the X-Niskin bottle was siphoned into a 250 cm3 glass bottle with enough seawater to fill the glass bottle two times. Immediately after sampling, 10 cm3 of seawater was removed from the bottle and poisoned by 50 µl of saturated HgCl2 solution. Then the bottle was sealed by a glass stopper with Apiezon M grease and stored in a cool and dark space on board. These procedures on board basically follow the methods described in WOCE Operation Manual (McNichol and Jones, 1991). Table 3.10.1: The sampling stations, number of samples, and maximum sampling pressure for carbon isotopes in DIC during MR07-04 and MRO7-06 cruises. No. re- Max. No. plicate sampling Cruise Station samples samples pressure/db ------- ------- ------- ------- ----------- MR07-04 P01-010 36 2 6501 MR07-04 P01-019 34 2 5314 MR07-04 P01-027 34 2 5242 MR07-04 P01-066 36 2 5853 MR07-04 P01-072 34 2 5499 MR07-04 P01-X15 34 2 5430 MR07-04 P01-081 34 2 5324 MR07-04 P0l-X16 33 2 5227 MR07-04 P0l-X17 31 2 4742 MR07-04 P01-097 30 2 4399 MR07-04 P01-101 29 2 4202 MR07-04 P01-108 23 1 2752 MR07-06 P01-032 34 2 5451 MR07-06 P01-038 33 2 5279 MR07-06 P0l-X13 36 2 6008 MR07-06 P01-048 29 2 4255 MR07-06 P01-056 36 2 5904 MR07-06 P01-060 36 2 5737 MR07-06 P14N-005 26 2 3529 MR07-06 P14N-011 28 2 3852 MR07-06 P14N-023 36 2 6500 MR07-06 P14N-X01 35 2 5718 MR07-06 P14N-042 32 2 4970 MR07-06 P14N-050 34 2 5487 MR07-06 P14N-056 25 1 3194 MR07-06 P14N-X02 30 2 4625 MR07-06 P14N-077 34 2 5838 MR07-06 P14N-087 32 2 4890 MR07-06 P14N-097 36 2 5780 MR07-06 P14N-X04 35 2 5706 MR07-06 P14N-125 35 2 5765 MR07-06 P14N-143 34 2 5497 MR07-06 P14N-160 35 2 5724 MR07-06 P14N-171 33 2 5084 MR07-06 P14N-180 25 1 3087 MR07-06 P14C-037 28 2 3838 MR07-06 P14C-028 31 2 4538 MR07-06 P14C-X06 29 2 4310 MR07-06 P14C-007 20 1 2012 Total 1245 74 (4) Sample preparation In our laboratory, DIC in the seawater samples were stripped cryogenically and split into three aliquots: Accelerator Mass Spectrometry (AMS) 14C measurement (about 200 µmol), 13C measurement (about 100 µmol), and archive (about 200 µmol). Efficiency of the CO2 stripping from seawater sample was more than 95 % that was calculated from concentration of DIC in the seawater samples. The stripped CO2 gas for 14C was then converted to graphite catalytically on iron powder with pure hydrogen gas. Yield of graphite powder from CO2 gas was estimated to be about 80% in average by weighing of sample graphite powder. Details of these preparation procedures were described by Kumamoto et al. (2011). (5) Sample measurements δ13C of the sample CO2 gas was measured using Finnigan MAT252 mass spectrometer. The δ13C value was calculated by a following equation: δ13C (‰) = (R(sample)/R(standard) - 1) × 1000. (1) where R(sample) and R(standard) denote 13C / 12C ratios of the sample CO2 gas and the standard CO2 gas, respectively. The working standard gas was purchased from Oztech Gas Co. and assigned δ13C value of -3.67 ‰ (Lot No. SHO-1250C) versus VPDB (Vienna Pee Dee Belemnite) standards. The gas has been calibrated relative to the appropriate internationally accepted IAEA primary standards. ∆14C in the graphite sample was measured at AMS facilities of Institute of Accelerator Analysis Ltd in Shirakawa (Pelletron 9SDH-2, National Electrostatic Corporation), Paleo Labo Co. Ltd in Kiryu (Compact-AMS, National Electrostatic Corporation), Japan Atomic Energy Agency in Mutsu (Model 41 30-AMS, High Voltage Engineering Europa), and National Institute for Environmental Studies in Tsukuba (Pelletron 9SDH-2, National Electrostatic Corporation). The ∆14C value was calculated by: δ14C(‰) = (R(sample)/R(standard) - 1) × 1000, (2) ∆14C(‰) = δ14C(‰) - 2(δ13C +25)(1 + δ14C/1000), (3) where R(sample) and R(standard) denote, respectively, 14C / 12C ratios of the sample and the international standard (NIST Oxalic Acid SRM4990-C). R(standard) was corrected for decay since A.D. 1950 (Stuiver and Polach, 1977; Stuiver, 1983). Equation 3 is normalization for isotopic fractionation. When quality of δ14C value was not "good", ∆14C was calculated by an interpolated δ13C value derived from data at just above and below layers. Finally ∆14C value was corrected for radiocarbon decay between the sampling and the measurement dates. Individual errors of δ13C were given by standard deviation of repeat measurements. Errors of ∆14C were derived from larger of the standard deviation of repeat measurements and the counting error. Means of the δ13C and ∆14C errors were calculated to be 0.004 ‰ (n = 1,073) and 2.5 ‰ (n = 1,070), respectively, which corresponds to "repeatability" of our δ13C and ∆14C measurements. δ13C and ∆14C in the seawater samples from stations P01_010, P01_027, P01_060, P01_072, and P01_097 (170 samples) were not measured due to shortage of research funds. (6) Replicate measurements Replicate samples were taken at all the stations. δ13C and ∆14C values in "good" quality were obtained from 64 pairs of the replicate samples (Table 3.10.2). The standard deviation of the δ13C and ∆14C replicate analyses was calculated to be 0.021 ‰ (n = 58) and 3.6 ‰ (n = 60), respectively. These were larger than the values of repeatability (0.004 and 2.5 %o, respectively) probably due to errors from the sample preparation, which corresponds to 'reproducibility' of our δ13C and ∆14C analyses. (7) Reference seawater measurements During the sample measurements period from October 2008 to March 2010, we also measured δ13C and ∆14C in reference seawaters together with those in the samples. The reference seawater (RS) was prepared from a large volume of surface seawater collected in an open ocean. The surface seawater was filtered, exposed to ultraviolet irradiation, poisoned by HgCl2, dispensed in 250 cm3 glass bottles, and then has been stored since July 2004. δ13C and ∆14C in one of the reference seawaters were measured at every suite of samples from a station (every 40 samples approx.). The results are shown in Table 3.10.3. The standard deviations (n = 32) of δ13C and ∆14C were 0.022 ‰ and 6.1 %o, respectively, which corresponds to 'uncertainty' of our δ13C and ∆14C analyses including error due to the sample preparation and sample storage. Table 3.10.2 Summary of replicate analyses. δ13C / ‰ ∆14C / ‰ ----------------------------------- ---------------------------------- E.W. Uncer- E.W. Uncer- Station Btl δ13C Error(a) Mean(b) tainty(c) ∆14C Error(d) Mean(b) tainty(c) ------- --- ----- -------- ------- --------- ----- -------- ------- --------- - - -12.3 1.9 P01-019 32 - - -8.7 5.2 - - -5.0 1.9 0.005 0.005 -231.2 1.5 P01-019 12 0.010 0.006 -232.8 2.4 0.014 0.004 -234.6 1.6 - - -63.4 1.7 P01-066 32 - - -62.8 1.2 - - -62.3 1.7 -0.051 0.003 -228.1 2.1 P01-066 12 -0.072 0.030 -225.2 3.2 -0.093 0.003 -223.6 1.6 0.081 0.003 -35.0 1.9 P01-X15 32 0.045 0.071 -33.0 3.5 -0.020 0.004 -30.1 2.3 -0.092 0.003 -227.4 1.7 P01-X15 12 -0.070 0.059 -227.9 1.2 -0.009 0.005 -228.4 1.6 0.145 0.003 -11.8 3.0 P01-081 32 0.134 0.016 -10.8 2.1 0.122 0.003 -9.9 2.9 -0.071 0.004 -241.4 2.6 P01-081 12 -0.062 0.007 -233.6 10.4 -0.061 0.001 -226.8 2.4 0.128 0.009 -14.8 1.7 P01-X16 32 0.128 0.002 -12.4 3.5 0.128 0.002 -9.9 1.7 -0.093 0.002 -241.4 1.6 P01-X16 12 -0.095 0.023 -239.0 3.3 -0.125 0.007 -236.7 1.6 0.015 0.002 -28.7 2.4 P01-X17 32 -0.013 0.040 -34.6 7.9 -0.041 0.002 -39.9 2.3 -0.005 0.004 -237.4 2.0 P01-X17 12 -0.012 0.010 -236.7 1.4 -0.019 0.004 -236.1 2.0 0.018 0.003 - - P01-101 32 0.024 0.006 - - 0.026 0.002 - - - - -237.2 1.6 P01-101 12 - - -240.7 4.7 - - -243.8 1.5 -0.310 0.005 -9.3 1.9 P01-108 32 -0.309 0.003 -9.3 1.3 -0.308 0.003 -9.3 1.9 -0.457 0.004 -98.1 2.9 P01-032 32 -0.458 0.003 -98.3 2.1 -0.460 0.005 -98.5 3.1 0.054 0.003 -222.3 2.6 P01-032 12 0.057 0.004 -222.5 1.8 0.059 0.003 -222.8 2.6 -0.821 0.006 -110.4 2.9 P01-038 32 -0.820 0.002 -112.6 3.0 -0.820 0.002 -114.7 2.9 0.057 0.004 -220.0 2.7 P01-038 12 0.062 0.012 -225.6 7.7 0.074 0.006 -231.0 2.6 -0.560 0.006 -100.6 2.3 P01-X13 32 -0.559 0.003 -98.7 2.7 -0.559 0.003 -96.8 2.3 0.042 0.003 -224.5 3.5 P01-X13 12 0.037 0.005 -223.9 2.5 0.035 0.002 -223.3 3.6 -0.556 0.005 -94.7 2.9 P01-048 32 -0.565 0.007 -93.6 2.0 -0.566 0.002 -92.5 2.8 - - -222.4 2.6 P01-048 12 - - -221.1 1.8 - - -219.8 2.6 -0.816 0.005 -101.7 2.2 P01-056 32 -0.750 0.054 -102.8 1.5 -0.739 0.002 -103.8 2.1 - - -224.5 1.8 P01-056 12 - - -226.3 2.8 - - -228.4 2.0 0.011 0.005 -63.9 3.2 P14N-005 32 0.015 0.004 -67.3 4.5 0.016 0.002 -70.2 3.0 -0.232 0.005 -230.5 2.7 P14N-005 12 -0.271 0.029 -229.6 2.0 -0.273 0.001 -228.6 2.8 -0.213 0.002 -74.0 3.0 P14N-011 32 -0.224 0.057 -73.0 2.1 -0.293 0.005 -72.0 2.9 -0.253 0.004 -234.9 2.6 P14N-011 12 -0.254 0.003 -227.7 10.7 -0.256 0.005 -219.7 2.8 -0.728 0.003 -106.1 3.2 P14N-023 32 -0.719 0.009 -107.0 2.1 -0.715 0.002 -107.8 2.9 0.038 0.004 -219.4 2.7 P14N-023 12 0.037 0.002 -219.0 1.9 0.036 0.003 -218.6 2.7 -0.211 0.004 -69.7 3.2 P14N-X01 32 -0.206 0.011 -68.5 2.2 -0.195 0.006 -67.5 2.9 0.004 0.006 -224.2 2.7 P14N-X01 12 0.009 0.004 -224.9 1.9 0.010 0.002 -225.6 2.8 0.405 0.004 34.2 4.3 P14N-042 32 0.401 0.004 33.0 3.3 0.399 0.003 31.4 5.1 -0.027 0.002 -229.4 3.6 P14N-042 12 -0.033 0.033 -231.2 2.6 -0.073 0.005 -233.1 3.7 0.392 0.003 38.0 3.8 P14N-050 32 0.397 0.007 34.9 4.2 0.402 0.003 32.0 3.6 0.030 0.002 -226.4 2.8 P14N-050 12 0.025 0.011 -224.1 3.3 0.015 0.003 -221.7 2.8 0.427 0.004 45.6 3.3 P14N-056 32 0.435 0.011 46.7 2.3 0.442 0.004 47.8 3.1 0.467 0.007 59.7 3.4 P14N-X02 32 0.462 0.004 59.3 2.4 0.461 0.003 58.9 3.4 0.033 0.005 -231.4 2.7 P14N-X02 12 0.058 0.029 -230.7 1.9 0.074 0.004 -230.1 2.6 0.316 0.002 46.0 3.3 P14N-077 29 0.320 0.010 47.5 2.3 0.330 0.003 49.0 3.3 0.087 0.002 -231.3 2.9 P14N-077 12 0.085 0.008 -227.9 4.6 0.075 0.005 -224.8 2.7 0.570 0.003 72.4 4.3 P14N-087 32 0.535 0.050 69.8 3.8 0.499 0.003 67.0 4.5 0.060 0.002 - - P14N-087 12 0.064 0.006 - - 0.068 0.002 - - 0.658 0.003 72.3 6.4 P14N-097 32 0.656 0.007 76.4 5.7 0.648 0.006 80.3 6.3 0.070 0.003 -230.6 3.9 P14N-097 12 0.059 0.011 -229.4 2.8 0.054 0.002 -228.2 3.9 -0.085 0.003 -7.9 2.1 P14N-X04 32 -0.085 0.001 -6.9 1.5 -0.085 0.001 -5.8 2.2 0.066 0.002 - - P14N-X04 12 0.068 0.004 - - 0.072 0.003 - - 0.403 0.004 -70.7 2.2 P14N-125 29 0.403 0.003 -65.8 6.9 0.402 ft004 -60.9 2.2 0.080 0.006 -223.5 1.5 P14N-125 12 0.092 0.011 -225.1 2.9 0.095 0.003 -227.6 1.8 0.693 0.005 73.0 2.0 P14N-143 32 0.696 0.003 70.8 2.8 0.697 0.003 69.1 1.8 0.125 0.003 -225.8 2.1 P14N-143 12 0.124 0.003 -222.6 3.8 0.121 0.004 -220.4 1.8 1.040 0.003 62.5 2.3 P14N-160 32 1.032 0.016 60.9 2.1 1.017 0.004 59.5 2.1 0.151 0.002 -219.1 1.7 P14N-160 12 0.154 0.014 -215.7 4.7 0.171 0.005 -212.4 1.7 0.634 0.003 -18.1 2.1 P14N-171 29 0.636 0.002 -17.8 1.4 0.637 0.003 -17.5 2.0 0.164 0.003 -225.0 2.4 P14N-171 12 0.184 0.028 -222.0 4.2 0.203 0.003 -219.0 2.4 0.978 0.003 85.7 3.0 P14N-180 32 0.979 0.002 88.1 3.6 0.980 0.004 90.8 3.2 0.928 0.004 - - P14C-037 32 0.935 0.010 - - 0.942 0.004 - - 0.260 0.003 -203.7 1.6 P14C-037 12 0.253 0.014 -203.8 1.1 0.240 0.004 -203.8 1.6 - - 89.0 1.8 P14C-028 32 - - 87.6 2.4 - - 85.6 2.1 0.252 0.003 -205.6 1.7 P14C-028 12 0.248 0.006 -204.7 1.3 0.244 0.003 -203.7 1.7 0.951 0.002 79.2 2.2 P14C-X06 32 0.952 0.004 79.8 1.6 0.956 0.006 80.4 2.2 0.232 0.004 -213.3 2.0 P14C-X06 12 0.224 0.009 -210.4 3.7 0.219 0.003 -208.0 1.8 1.011 0.002 52.9 2.4 P14C-007 32 1.005 0.014 53.6 1.6 0.991 0.003 54.1 2.2 a. Standard deviation of repeat measurements. b. Error weighted mean of the replicate pair. c. Larger of the standard deviation and the error weighted standard deviation of the replicate pair. d. Larger of the standard deviation of repeat measurements and the counting errors. Table 3.10.3: Summary of δ13C and ∆14C measurements in the reference seawaters (RS). δ13C / ‰ ∆14C(a) / ‰ ------------------------ ---------------------- Measure- Error Measure- Error No. RS No. ment date δ13C (b) ment date ∆14C (c) --- ---------- --------- ------ ----- --------- ---- ----- 1 RM0407-162 10-Sep-09 -0.908 0.002 09-Oct-09 38.9 2.0 2 RM0407-165 14-Sep-09 -0.902 0.003 16-Oct-09 43.9 2.0 3 RM0407-160 19-Jan-10 -0.903 0.005 23-Oct-09 38.6 1.9 4 RM0407-115 21-Jan-10 -0.908 0.003 13-Nov-09 39.1 1.9 5 RM0407-33 01-Feb-10 -0.887 0.005 27-Nov-09 26.6 2.3 6 RM0407-136 03-Feb-10 -0.900 0.003 18-Dec-09 22.8 1.8 7 RM0407-145 04-Feb-10 -0.926 0.005 11-Mar-10 37.6 3.2 8 RM0407-60 11-Sep-08 -0.856 0.004 07-Oct-08 31.8 3.3 9 RM0407-173 16-Sep-08 -0.890 0.003 07-Oct-08 31.7 3.2 10 RM0407-30 07-Oct-08 -0.876 0.004 31-Oct-08 32.5 3.4 11 RM0407-17 08-Oct-08 -0.881 0.002 31-Oct-08 23.6 3.3 12 RM0407-181 04-Sep-08 -0.924 0.002 08-Oct-08 40.4 4.4 13 RM0407-134 05-Nov-08 -0.891 0.005 15-Dec-08 37.3 3.4 14 RM0407-142 13-Nov-08 -0.891 0.004 15-Dec-08 36.1 3.3 15 RM0407-137 17-Nov-08 -0.888 0.003 15-Dec-08 39.3 3.2 16 RM0407-19 04-Nov-08 -0.897 0.004 11-Nov-08 27.2 3.4 17 RM0407-61 09-Dec-08 -0.866 0.003 01-Apr-09 25.6 4.4 18 RM0407-62 13-Jan-09 -0.883 0.003 07-Apr-09 35.5 6.2 19 RM0407-63 15-Jan-09 -0.873 0.004 14-May-09 45.9 2.1 20 RM0407-34 09-Feb-09 -0.931 0.005 27-May-09 26.2 2.7 21 RM0407-85 12-Feb-09 -0.922 0.002 12-Jun-09 40.0 1.8 22 RM0407-41 16-Mar-09 -0.883 0.005 19-Jun-09 36.2 1.9 23 RM0407-84 18-Mar-09 -0.911 0.006 06-Jul-09 42.2 2.1 24 RM0407-95 19-May-09 -0.892 0.005 05-Aug-09 28.0 3.0 25 RM0407-21 20-May-09 -0.933 0.002 28-Aug-09 31.2 1.9 26 RM0407-108 21-May-09 -0.957 0.004 04-Sep-09 30.9 1.8 27 RM0407-179 23-Jul-09 -0.892 0.006 05-Sep-09 24.9 2.5 28 RM0407-4 16-Jun-09 -0.880 0.002 11-Sep-09 33.4 2.0 29 RM0407-105 18-Jun-09 -0.916 0.003 18-Sep-09 35.3 2.1 30 RM0407-7 21-Jul-09 -0.899 0.002 26-Oct-09 35.3 3.1 31 RM0407-187 22-Jul-09 -0.913 0.006 26-Oct-09 34.7 3.1 32 RM0407-5 08-Feb-10 -0.881 0.004 16-Mar-10 37.4 3.1 a. Decay corrected for 01/July/2004. b. Standard deviation of repeat measurements. c. Larger of the standard deviation and the counting error. (8) Quality control flag assignment Quality flag values were assigned to all δ13C and ∆14C measurements using the code defined in Table 0.2 of WHP Office Report WHPO 91-1 Rev.2 section 4.5.2 (Joyce et al., 1994). Quality flags of 2, 3, 4, 5, and 6 have been assigned (Table 3.10.4). For the choice between 2 (good), 3 (questionable), or 4 (bad), we basically followed a flagging procedure in Key et al. (1996) as listed below: a. On a station-by-station basis, a datum was plotted against pressure. Any points not lying on a generally smooth trend were noted. b. δ13C (∆14C) was then plotted against dissolved oxygen (alkalinity) concentration and deviant points were noted. If a datum deviated from both the depth and oxygen (alkalinity) plots, it was flagged 3 (questionable). c. Vertical transections against depth were prepared using the Ocean Data View (Schlitzer, 2012). If a datum was anomalous on the transection plots, datum flag was degraded from 2 to 3, or from 3 to 4. Quality flags of δ13C and ∆14C for all the samples from stations P01-010, P01-027, P01-060, P01-072, and P01-097 (170 samples) were assigned to be 5. Table 3.10.4: Summary of assigned quality control flags Number Flag Definition ---------- δ13C ∆14C ---- -------------------- ---- ---- 2 Good 931 952 3 Questionable 84 58 4 Bad 0 0 5 Not report (missing) 172 175 6 Replicate 58 60 Total 1245 1245 (9) Data Summary Figure 3.10.2 shows vertical transection of δ13C against depth. Higher δ13C values were observed in surface waters. Along the meridional line higher values were found in the southern subtropical region. Minimum of δ13C was found in deep waters from 500 to 2,000 m depth approximately in the North Pacific and the smallest value was in the deep waters of the subarctic region. From the deep to the bottom waters δ13C increases gradually. The general distribution of δ13C well agrees with that presented in a previous study (Kroopnick, 1985) and is mainly governed both by biogeochemical process and ocean circulation. Figure 3.10.3 shows vertical transection of ∆14C against depth. Higher ∆14C values were observed in the thermocline (< about 1,000 m depth) because of the bomb-produced radiocarbon penetration. In the North Pacific relative higher ∆14C was measured in bottom waters below 4,000 m depth approximately where the high- δ13C water was observed, which is derived from a northward transport of the Circumpolar Deep Water from the South Pacific. Minimum of ∆14C was found in deep waters from 1,500 to 4,000 m depth approximately. The general distribution of ∆14C in deep and bottom waters supports a previous study (Key et al., 2004) and indicates the global pattern of thermohaline circulation. Figure 3.10.2: Vertical transections of δ13C (‰) against depth along the WHP-P01 (upper, 47°N approx.) and WHP-P14NC (lower, 179°E approx.) lines in 2007. Figure 3.10.3: Same as the Figure 3.10.2 but for ∆14C (‰). References Joyce, T., and C. Cony, eds., C. Corry, A. Dessier, A. Dickson, T. Joyce, M. Kenny, R. Key, D. Legler, R. Millard, R. Onken, P. Saunders, M. Stalcup, contrib., 1994. Requirements for WOCE Hydrographic Programme Data Reporting, WHPO Pub. 90-1 Rev. 2, l45pp. Kawano, T, H. Uchida, and T. Doi, 2009. WHP P01, P14 Revisit Data Book, JAMSTEC, Yokosuka. pp 212. Key, R.M., A. Kozyr, C.L. Sabine, K. Lee, R. Wanninkhof, J.L. Bullister, R.A. Feely, F.J. Millero, C. Mordy, T.H. Peng, 2004. A global ocean carbon climatology: Results from Global Data Analysis Project (GLODAP), Global Biogeochemical Cycles, 18, GB403 1, doi: 10.1 029/2004GB002247. Key, R.M., P.D. Quay, G.A. Jones, A.P. McNichol, K.F. von Reden, R.J. Schneider, 1996. WOCE AMS radiocarbon I: Pacific Ocean results (P6, P16, P17), Radiocarbon 38, 425-518. Kroopnick, P.M., 1985. The distribution of 13C of CO2 in the world oceans, Deep-Sea Research, 32, 5784. Kumamoto Y, A. Murata, S. Watanabe, M. Fukasawa, 2011. Temporal and spatial variations in bomb radiocarbon along BEAGLE2003 lines-Revisits of WHP P06, Ab, and 103/104 in the Southern Hemisphere Oceans, Progress in Oceanography 89, 49-60. McNichol, A.P. and G.A. Jones, 1991. Measuring 14C in seawater CO2 by accelerator massspectrometry, WOCE Operations Manual, WOCE Report No.68/91, Woods Hole, MA. Schlitzer R., 2012. Ocean Data View. URL: Stuiver. M., 1983. International agreements and the use of the new oxalic acid standard, Radiocarbon, 25, 793-795. Stuiver, M. and H.A. Polach, 1977. Reporting of 14C data. Radiocarbon 19, 355-363. FIGURE CAPTIONS Figure 1(a): Station locations for WHP P01 cruise with bottom topography based on Smith and Sandwell (1997). Figure 1(b): Station locations for WHP P14 cruise with bottom topography based on Smith and Sandwell (1997). Figure 2(a): Bathymetry measured by Multi Narrow Beam Echo Sounding system for WHP-P01. Cross mark indicates CTD location. Figure 2(b): Bathymetry measured by Multi Narrow Beam Echo Sounding system for WHP-P14. Cross mark indicates CTD location. Figure 3: Surface wind measured at 25 m above sea level. Wind data is averaged over 1-hour and plotted every 0.5 degree in latitude. (a) WHP-P01 (b) WHP-P14 Figure 4: Sea surface temperature (SST). Temperature data is averaged over 1- hour (a) WHP-P01 (b) WHP-P14 Figure 5: Sea surface salinity (SSS). Salinity data is averaged over 1-hour. (a) WHP-P01 (b) WHP-P14 Figure 6: Difference in the partial pressure of CO2 between the ocean and the atmosphere, ∆pCO2. (a) WHP-P01 (b) WHP-P14 Figure 7: Surface current at 100 m depth measured by shipboard acoustic Doppler current profiler (ADCP). (a) WHP-P01 (b) WHP-P14 Figure 8: Potential temperature (°C) cross section calculated by using CTD temperature and salinity data calibrated by bottle salinity measurements. Vertical exaggeration of the 0-6,500 m section is 1000:1. Expanded section of the upper 1000 m is made with a vertical exaggeration of 2500:1. (a) WHP-P01 (b) WHP-P14 Figure 9: CTD salinity (psu) cross section calibrated by bottle salinity measurements. Vertical exaggeration is same as Figure 8. (a) WHP- P01 (b) WHP-P14 Figure 10: Same as Figure 9 but with SSW batch correction1. (a) WHP-P01 (b) WHP-P14 Figure 11: Density (σ0) (kg/m3) cross section calculated using CTD temperature and calibrated salinity data with SSW batch correction. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 12: Same as Figure 11 but for σ4 (kg/m3). (a) WHP-P01 (b) WHP-P14 Figure 13: Neutral density (γn) (kg/m3) cross section calculated using CTD temperature and calibrated salinity data with SSW batch correction. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 14: Cross section of bottle sampled dissolved oxygen (µmol/kg). Data with quality flags of 2 were plotted. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 15: Silicate (µmol/kg) cross section. Data with quality flags of 2 were plotted. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 16: Nitrate (µmol/kg) cross section. Data with quality flags of 2 were plotted. Vertical exaggeration of the upper 1000 m section is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 17: Nitrite (µmol/kg) cross section. Data with quality flags of 2 were plotted. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 18: Phosphate (µmol/kg) cross section. Data with quality flags of 2 were plotted. Vertical exaggeration is same as Figure 8. (a) WHP- P01 (b) WHP-P14 Figure 19: Dissolved inorganic carbon (µmol/kg) cross section. Data with quality flags of 2 were plotted. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 20: Total alkalinity (µmol/kg) cross section. Data with quality flags of 2 were plotted. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 21: pH cross section. Data with quality flags of 2 were plotted. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 22: CFC-11 (pmol/kg) cross section. Data with quality flags of 2 were plotted. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 23: CFC-12 (pmol/kg) cross section. Data with quality flags of 2 were plotted. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 24: CFC-113 (pmol/kg) cross section. Data with quality flags of 2 were plotted. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 25: Cross section of current velocity (cm/s) normal to the cruise track measured by LADCP (northward is positive). (a) WHP-P01 (b) WHP-P14 Figure 26: Difference in potential temperature (°C) between results from WOCE (from Oct. to Nov., 1993) and the revisit cruise (from May to Jul., 2005). Red and blue areas show the areas where potential temperature increased and decreased in the revisit cruise, respectively. On white areas differences in temperature do not exceed the detection limit of 0.002°C. Vertical exaggeration is same as Figure 8. (a) WHP -P01 (b) WHP-P14 Figure 27: Difference in salinity (psu) between results from WOCE and the revisit cruise. Red and blue areas show the areas where salinity increased and decreased in the revisit cruise, respectively. CTD salinity data with SSW batch correction1 are used. On white areas differences in salinity do not exceed the detection limit of 0.002 psu. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Figure 28: Difference in dissolved oxygen (µmol/kg) between results from WOCE and the revisit cruise. Red and blue areas show the areas where salinity increased and decreased in the revisit cruise, respectively. Bottle oxygen data are used. On white areas differences in salinity do not exceed the detection limit of 2 µmol/kg. Vertical exaggeration is same as Figure 8. (a) WHP-P01 (b) WHP-P14 Note 1. As for the traceability of SSW to Mantyla's value, the offset for the batches P120 (P14C), P122 (P14N), P133 (P01E and P01W), P134 (P01C, a part of P01E and P01H) and P148 (Revisit) is -0.0022, -0.0009, -0.0010, -0.0011 and -0.0011, respectively (The newest values, Kawano et al., in preparation). REFERENCES Jackett, D. R. and R. J. McDougall (1997): A neutral density variable for the world's oceans, Journal of Physical Oceanography, 27, 237-263. Smith, W. H. F. and D. T. Sandwell (1997): Global seafloor topography from satellite altimetry and ship depth soundings, Science, 277, 1956-1962. DATA PROCESSING NOTES DATE PERSON DATE TYPE EVENT SUMMARY ---------- ---------- ------------- --------------- ----------------------- 2009-02-02 Kawano CTD/BTL/SUM Submitted on CD P01 We published a databook of WHP-POI, PI4 Revisit. The data in the P14 Leg 1 databook have been submitted to CCHDO and CDIAC, therefore all data P14 Leg 2 and figures in the databook are free to use. However, it would be grateful if you refer this databook and kindly inform us when you use the data and figures in the databook. Your reference and kind support will surely make Japanese government to support hydrographic activities under International Repeat Hydrography and Carbon Program. 2009-04-23 Kozyr pH Submitted new headers P01 Here is corrected .hy1 file for the P01_2007 cruise. I changed PH P14 Leg 1 column to PH_TOT, added PH_TMP column and changed EXPOCODE to 49NZ20070724. Please, replace the old file with this one. Here is the corrected P14_2007 Leg 1 hy1 file. I changed PH column to PH_TOT, added PH_TMP column and changed EXPOCODE to 49NZ20071008. I would suggest to organize this cruise on as P14_2007 Leg 1 and P14_2007 Leg 2 in CCHDO web site. For now you have P14N and P14C wich is not completely correct, as a half of P14C consists of data from P14N. And 1/3 of the data in P14N file are from P01 line. 2009-04-23 Kozyr pH Submitted new headers P14 Leg 2 Expo: 49NZ20071122 (49MR0706_2) Line: P14_2007 Leg 2 Date: 2007-11-22 Action: Place Online Notes: Here is the corrected P14_2007 Leg 2 hy1 file. I changed PH column to PH_TOT, added PH_TMP column and changed EXPOCODE to 49NZ20071122. I also would suggest to organize this cruise as P14_2007 Leg 1 and P14_2007 Leg 2 in CCHDO web site. For now you have P14N and P14C wich is not completely correct, as a half of P14C consists of data from P14N. And 1/3 of the data in P14N file are from P01 line. 2009-08-18 Bartolocci CTD/BTL/SUM Website Updated All files reformatted P01 Edited the following: EXCHANGE BOT FILE ------------- Parameter Header: SIG0 to STHETA SECT to SECT_ID PH to PH_TOT (as per doc file) Units Header: KG and MBQ //CUM to /M^3 removed UTC (from TIME) removed DEG (from Lat and Lon) removed M from DEPTH Added CS137ER to our parameter table Added CTDPRS_FLAG_W, CTDTEMP_FLAG_W to our parameter groups table (in appropriate order) First Header: edited EXOCODE from 49MR0704_1 to 49NZ20070724 added name/date stamp copy_bottle_data.rb was used to place all the parameters in the accepted exchange parameter order. File was renamed p01_49NZ20070724_hy1.csv File was checked with JOA. WOCE BOT FILE ---------- Parameter Header: SIG0 to STHETA PH to PH_TOT Units Header: KG and MBQ /CUM to /M^3 Data: edited EXOCODE from 49MR0704_1 to 49NZ20070724 added WHP-ID and name/date stamp Ran wocecvt, however the file contains many non-WOCE parameters which therefore renders format checking impossible. SUMFILE ------- Data: edited EXOCODE from 49MR0704_1 to 49NZ20070724 Header: added name/date stamp ran sumchk with no errors. renamed file p01_49NZ20070724su.txt WOCE CTD FILES -------------------------- Edited EXPOCODE from 49MR0704_1 to 49NZ20070724 Edited FLUOR units from MG/CUM to MG/M^3 Zipped all files into p01_49NZ20070724ct.zip EXCHANGE CTD FILES --------------------------------- Edited EXPOCODE from 49MR0704_1 to 49NZ20070724 Edited FLUOR units from MG/CUM to MG/M^3 Renamed individual station files to adhere to exchange file naming conventions. Zipped all files into p01_49NZ20070724_ct1.zip NETCDF BOTTLE/CTD FILES ---------------------------------------- NetCDF bottle and ctd files were generated using the respective reformatted exchange files, provided by the data originators. Files converted without errors. Bottle file named: p01_49NZ20070724_nc_hyd.zip. CTD file named p01_49NZ20070724_nc_ctd.zip. Files have been placed online and cchdo_update script run. 2009-09-23 Uchida CTDOXY Submitted Updated file P01 The CTD oxygen data were updated after the data book was published P14 Leg 1 by Kawano et al. (2009). In the data book, data from two oxygen P14 Leg 2 optode sensors (Oxygen Optode 3830; Aanderaa Data Instruments AS, Bergen, Norway, and RINKO; JFE Alec Co. Ltd., Kobe, Japan) were combined and used because data quality of the SBE 43 oxygen sensor was relatively bad (Kawano et al., 2009) for the cruise MR07-04. Data from the two oxygen optode sensors were combined because the Optode 3830 had a slow time response without pressure hysteresis and the RINKO had a fast time response with pressure hysteresis. The time-dependent, pressure-induced effect (pressure hysteresis) on the sensing foil of the RINKO was similarly observed in the SBE 43 data. Recently, a correction method of the pressure hysteresis was developed for the SBE 43 (Sea-Bird Electronics, 2009), and the correction method was successfully applied to the RINKO (Murata, 2009). Therefore, the RINKO data were reprocessed, calibrated, and used as the CTD oxygen data for the cruises MR07-04 and MR07-06. 2009-11-10 Bartolocci CTD/BTL/SUM Website Updated All files reformatted P14 Leg 1 WOCE Bottle: Because this cruise contained the two lines P01 and P14N, which both had overlapping station numbers, two separate bottle files were retained and each reformatted individually. The following edits were applied to both files. original files named: 49MR0706_1_P01_sea.txt, 49MR0706_1_P14N_sea.txt Edited EXPOCODE from 49MR0706_1 to 49NZ20071008 for both line numbers Added name/date stamp Edited PH to PH_TOT as per the documentation file Edited SIG0 units from KG/CUM to KG/M^3 Edited CS-137 and PLUTO parameters' units from BQ/CUM to BQ/M^3 Formatted WOCE files are named: p01_49NZ20071008hy.txt and p14n_49NZ20071008hy.txt EXCHANGE Bottle: original file named: 49MR0706_1_hy1.csv Edited SECT to SECT_ID Edited PH to PH_TOT (as per doc file) Edited units of KG and MBQ /CUM to /M^3 removed units UTC (from TIME) removed units DEG (from Lat and Lon) removed units M (from DEPTH) Edited EXOCODE from 49MR0706_1 to 49NZ20071008 added name/date stamp copy_bottle_data.rb was used to place all the parameters in the accepted exchange parameter order. File was renamed p14_49NZ20071008_hy1.csv SUMFILE: original file named: 49MR0706_1_sum.txt edited EXOCODE from 49MR0706_1 to 49NZ20071008 added name/date stamp ran sumchk with no errors. renamed file p14_49NZ20071008su.txt WOCE CTD FILES: original zip file named: 49MR0706_1_wct.zip Edited EXPOCODE from 49MR0706_1 to 49NZ20071008 Edited FLUOR units from MG/CUM to MG/M^3 Zipped all files into p14_49NZ20071008ct.zip EXCHANGE CTD FILES: original zip file named: 49MR0706_1_ct1.zip Edited EXPOCODE from 49MR0706_1 to 49NZ2007108 Edited FLUOR units from MG/CUM to MG/M^3 zipped all files into p14_49NZ20071008_ct1.zip created netcdf bottle and exchange files with no apparent errors. bottle file: p14_49NZ20071008_nc_hyd.zip CTD zip file: p14_49NZ20071008_nc_ctd.zip Checked exchange files in JOA. Placed data online. Updated data history. 2010-02-01 Bartolocci CTD/BTL/SUM Website Updated All files reformatted P14 Leg 2 Reformatting Notes for P14_49NZ20071122 All Files. WOCE Bottle: Because this cruise contained the two lines P14C and P14N, which both had overlapping station numbers, two separate WOCE bottle files were retained and each reformatted individually. The following edits were applied to both files. original files named: 49MR0706_2_P14C_sea.txt, 49MR0706_2_P14N_sea.txt Edited EXPOCODE from 49MR0706_2 to 49NZ20071122 for both line numbers Added name/date stamp Edited PH to PH_TOT as per the documentation file Edited SIG0 units from KG/CUM to KG/M^3 Edited CS-137 and PLUTO parameters' units from BQ/CUM to BQ/M^3 Formatted WOCE files are named: p14c_49NZ20071122hy.txt and p14n_49NZ20071122hy.txt EXCHANGE Bottle: original file named: 49MR0706_2_hy1.csv Edited SECT to SECT_ID Edited PH to PH_TOT (as per doc file) Edited units of KG and MBQ /CUM to /M^3 removed units UTC (from TIME) removed units DEG (from Lat and Lon) removed units M (from DEPTH) Edited EXOCODE from 49MR0706_2 to 49NZ20071122 added name/date stamp copy_bottle_data.rb was used to place all the parameters in the accepted exchange parameter order. File was renamed p14_49NZ20071122_hy1.csv SUMFILE: original file named: 49MR0706_2_sum.txt edited EXOCODE from 49MR0706_2 to 49NZ20071122 added name/date stamp ran sumchk with no errors. renamed file p14_49NZ20071122su.txt WOCE CTD FILES: original zip file named: 49MR0706_2_wct.zip Edited EXPOCODE from 49MR0706_2 to 49NZ20071122 Edited FLUOR units from MG/CUM to MG/M^3 Zipped all files into p14_49NZ20071122ct.zip EXCHANGE CTD FILES: original zip file named: 49MR0706_2_ct1.zip Edited EXPOCODE from 49MR0706_2 to 49NZ20071122 Edited FLUOR units from MG/CUM to MG/M^3 zipped all files into p14_49NZ20071122_ct1.zip NETCDF: created netcdf bottle and exchange files with no apparent errors. bottle file: p14_49NZ20071122_nc_hyd.zip CTD zip file: p14_49NZ20071122_nc_ctd.zip Checked exchange files in JOA. Placed data online. Updated data history. 2010-02-19 Bartolocci BTL Website Updated Temp. move to Queue Directory P01 WOCE-formatted bottle files have been zipped together and are P14 Leg 1 temporarily residing in the Queue directory. This should be P14 Leg 2 regarded as temporary, since the queue is for unprocessed updates, which these are not. However, our system can not handle two of any formatted files getting linked to the cruise pages. Jim Swift has made the decision to assign each leg/line of the individual cruises their own expocode and split them apart, with each line referencing the other for these two p14 cruises. Until this is done, the WOCE-formatted files will need to reside in the queue directory. 2010-08-10 Fields CTD/BTL/SUM Related Cruise Additional P01 stations available P01 There are additional stations for the 2007 P01 line available in the 2007 P14 (49NZ20071009) files. These additional stations cover from around 150E to 175W. 2010-08-31 Berys pH Website Updated Exchange file headers updated P14 Leg 1 p14_49NZ20071008_hy1.csv datestamp 20100830CCHDOSIOCBG The following actions were taken: File merged with PH headers submitted by Alex Kozyr on 2009-04-24 with merge_exchange_bot.rb (J.Fields) submission file 20090424_08_38_Alexander_Kozyr/P14_2007_Leg1_hy1.csv parameters merged: PH_TEMP, PH_TOT, PH_FLAG_W The following units were changed: PH_TMP from 'ITS-90' to 'DEG C' DEPTH from [blank] to 'METERS' C14ERR from [blank] to '/MILLE' C13ERR from [blank] to '/MILLE' SBE from [blank] to 'ITS-90' SILUNC from [blank] to 'UMOL/KG' NRAUNC from [blank] to 'UMOL/KG' NRIUNC from [blank] to 'UMOL/KG' PHPUNC from [blank] to 'UMOL/KG' File opened in JOA, no errors found NOTE: WOCE and NetCDF files do not have updated PH headers working directory: original/2010.08.24_P142007_1_PH_header_CBG/ 2010-08-31 Berys pH Website Updated Exchange file headers updated P14 Leg 2 p14_49NZ20071122_hy1.csv datestamp 20100901CCHDOSIOCBG The following actions were taken: File merged with PH headers submitted by Alex Kozyr on 2009-04-24 with merge_exchange_bot.rb (J.Fields) submission file 20090424_08_43_Alexander_Kozyr/P14_2007_Leg2_hy1.csv parameters merged: PH_TEMP, PH_TOT, PH_FLAG_W The following units were changed: PH_TMP from 'ITS-90' to 'DEG C' DEPTH from [blank] to 'METERS' C14ERR from [blank] to '/MILLE' C13ERR from [blank] to '/MILLE' SBE from [blank] to 'ITS-90' SILUNC from [blank] to 'UMOL/KG' NRAUNC from [blank] to 'UMOL/KG' NRIUNC from [blank] to 'UMOL/KG' PHPUNC from [blank] to 'UMOL/KG' File opened in JOA, no errors found NOTE: WOCE and NetCDF files do not have updated PH headers working directory: original/2010.08.31_P142007_2_PH_header_CBG/ 2011-11-17 Kappa Cruise Report Website Updated new CTDOXY section P01 A new section regarding CTDOXY data, submitted by Hiroshi Uchida on P14 Leg 1 22009-09-23, has been added to the online PDF report, along with P14 Leg 2 expanded Data Processing Notes. 2014-11-14 Kappa Cruise Report Website Updated new C14 section P01 A new section regarding C14 data, provided by Bob Key on 2014-07-11, P14 Leg 1 has been added to the online PDF report, along with expanded Data P14 Leg 2 Processing Notes.