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CRUISE REPORT: P10
(Updated Mar 2015)














Highlights

                                Cruise Summary Information

               Section Designation  P10 leg 2                  P10 leg 3
Expedition designation (ExpoCodes)  49NZ20111220 (MR11-08)     49NZ20120113 (MR11-08)
                  Chief Scientists  Akihiko Murata             Yuichiro Kumamoto
                             Dates  2011 Dec 20 - 2012 Jan 12  2012 Jan 13 - 2012 Feb 09
                                    Ship  R/V Mirai
                     Ports of call  Koror, Palau - Guam, USA   Guam, USA - Sekinehama, JPN 

                                                         43° N
             Geographic Boundaries  140° E                                  151° E
                                                         10° S

                          Stations  69  43
      Floats and drifters deployed  2 Argo Floats
    Moorings deployed or recovered  0

                                   Contact Information:
   Ocean Climate Change Research Program • Research Institute for Global Change (RIGC)
              Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
                   2-15 Natsushima, Yokosuka, Kanagawa, Japan 237-0061
      Fax: +81-46-867-9835 • Email: murataa@jamstec.go.jp     kumamoto@jamstec.go.jp










WHP P10 REVISIT IN 2011 DATA BOOK

                                                              Edited by
                                              Hiroshi Uchida (JAMSTEC),
                                              Akihiko Murata (JAMSTEC),
                                               Toshimasa Doi (JAMSTEC)

                         WHP P10 Revisit in 2011

                                 Towards
                                 Intl. Repeat Hydrography
                                 and Carbon Program


WHP P10 REVISIT IN 2011 DATA BOOK

March 20, 2014 Published
Edited by Hiroshi Uchida (JAMSTEC), Akihiko Murata (JAMSTEC) and 
Toshimasa Doi (JAMSTEC)

Published by © JAMSTEC, Yokosuka, Kanagawa, 2014
Japan Agency for Marine-Earth Science and Technology
2-15 Natsushima, Yokosuka, Kanagawa. 237-0061, Japan
Phone +81-46-867-9474, Fax +81-46-867-9835

Printed by Aiwa Enterprise, Ltd.
3-22-4 Takanawa, Minato-ku, Tokyo 108-0074, Japan



Contents

Preface 
  M. Fukasawa (JAMSTEC)

Documents and station summary files
  1  Cruise Narrative 
       A. Murata and Y. Kumamoto (JAMSTEC)

  2  Underway Measurements
  2.1  Navigation 
  2.2  Swath Bathymetry 
       T. Matsumoto (Univ. Ryukyu), N. Hirano (Tohoku Univ.) et al.
  2.3  Surface Meteorological Observation 
       K. Yoneyama (JAMSTEC) et al.
  2.4  Thermo-Salinograph and Related Measurements 
       H. Uchida (JAMSTEC) et al.
  2.5  Underway pCO2 
       A. Murata (JAMSTEC) et al.
  2.6  Shipboard ADCP 
       S. Kouketsu (JAMSTEC) et al.
  2.7  XCTD 
       H. Uchida (JAMSTEC) et al.

  3  Hydrographic Measurement Techniques and Calibrations
  3.1  CTDO2 Measurements 
       H. Uchida (JAMSTEC) et al.
  3.2  Bottle Salinity 
       H. Uchida (JAMSTEC) et al.
  3.3  Density 
       H. Uchida (JAMSTEC)
  3.4  Oxygen 
       Y. Kumamoto (JAMSTEC) et al.
  3.5  Nutrients 
       M. Aoyama (MRI/JMA) et al.
  3.6  Chlorofluorocarbons and Sulfur Hexafluoride 
       K. Sasaki (JAMSTEC) et al.
  3.7  Dissolved Inorganic Carbon (CT) 
       A. Murata (JAMSTEC) et al.
  3.8  Total Alkalinity (AT) 
       A. Murata (JAMSTEC) et al.
  3.9  pH 
       A. Murata (JAMSTEC) et al.
  3.10 Chlorophyll a 
       O. Yoshida (Rakuno Gakuen Univ.), H. Uchida (JAMSTEC) et al.
  3.11 LADCP 
       S. Kouketsu (JAMSTEC) et al.
 
  Station Summary (see PDF version or data files)


Figures
  Figure captions 
  Station locations 
  Bathymetry 
  Surface wind 
  Sea surface temperature, 
  salinity, 
  oxygen, 
  chlorophyll a 
  ΔpCO2 
  Surface current 
  Cross-sections
  Potential temperature 
  CTD salinity 
  Absolute salinity 
  Density (σ0) (EOS-80) 
  Density (σ0) (TEOS-10) 
  Density (σ4) (EOS-80) 
  Density (σ4) (TEOS-10) 
  Density (γn) 
  CTD oxygen 
  CTD chlorophyll a 
  Bottle sampled dissolved oxygen 
  Silicate 
  Nitrate 
  Nitrite 
  Phosphate 
  Dissolved inorganic carbon (CT) 
  Total alkalinity (AT) 
  pH (pHT) 
  CFC-11 
  CFC-12 
  CFC-113 
  Velocity 
  
Difference between previous occupations and the revisit
  Potential temperature (2011-1993) 
  (2011-2005) 
  CTD Salinity (2011-1993) 
  (2011-2005) 
  CTD oxygen (2011-1993) 
  (2011-2005) 

.sum, .sea, .wct and other data files CD-ROM on the back cover (see 
online data files)




PREFACE

At 14:46 on 11 March 2011, Japan was attacked by the huge catastrophe 
earthquake with magnitude of 9.0. The epicenter of the earthquake widely 
distributed along the Japan trench off the east coasts of Tohoku district. 
Unprecedented tragedies were brought about by the Tsunami which attacked the 
Pacific coast of eastern Japan twenty minutes after the earthquake. More than 
18,000 people were killed or lost by this Tsunami. Moreover, the Fukushima 
First Nuclear Power Plant was destroyed by the Tsunami and considerable 
amount of radio nuclides were discharged from the power plant into the 
atmosphere and the ocean.

Right after the earthquake, we, Research Institute for Global Change started 
to monitor and forecast the dispersion of the discharged radio nuclides off 
coast of Fukushima under the request from the Japanese government. It was 
very hard task for scientists in RIGC/JAMSTEC to conduct ocean monitoring and 
prediction, nevertheless, RIGC/JAMSTEC was expected to be deeply engaged in 
the task because RIGC is the only institute which has the ability to pursue 
the governmental requests.

Facing the Fukushima Disaster brought about by the earthquake, RIGC/JAMSTEC 
changed the cruise plan for GO-SHIP hydrographic observation. As the result, 
RIGC/JAMSTEC decided to re-occupy P10 in the western North Pacific Ocean 
instead of I08N/I05E in the Indian Ocean since we believed this change of our 
plan made it possible for the world GO-SHIP community to build a data network 
on radio nuclides in the western North Pacific within three years together 
with US cruise along P02 in 2013 and RIGC/JAMSTEC cruise along P01 in 2014. 
The preparation for the original plan to re-occupy the line in the Indian 
Ocean had been proceeded under collaboration with Sri Lanka and India. Thus, 
here, I would like to express my heartfelt thanks to all those concerned in 
both countries for their kind acceptance of our sudden changes of the cruise 
at that time.

The cruise along P10 was started on 20 December 2011 from Palau. Stations 
were set to reoccupy the stations which were observed in 2005 by IORGC, a 
predecessor of RIGC/JAMSTEC, namely 124 stations on the cruise track from 
Papua New Guinea to Hokkaido. We completed the cruise on 9 February 2012, 
however, bad weather and sea condition forced us to decrease the number of 
CTD/water sampling stations in the northern part of the cruise.

Of course, this cruise was carried out as Japanese activity within the 
framework of GO-SHIP. On the other hand, we had our specific objective for 
this cruise that was to prepare data network for radio nuclides in the 
western North Pacific Ocean after the Fukushima Disaster. It was the reason 
why we placed larger priority on the northern part of P10 in the cruise. Now, 
the data including results from chemical analysis can be used by anyone 
through this data book and websites of JAMSTEC, CCHDO and CDIAC.

Lastly, I would like to ask favors of all scientists to refer our data book 
as often as possible. Such reference from scientists proves the scientific 
importance of GO-SHIP and consequently helps RIGC/JAMSTEC to continue GO-SHIP 
activity.

On the memorial day after three years of the Tragic Earthquake and Tsunami

Masao Fukasawa

Research Director RIGC/JAMSTEC



*Acronyum

RIGC     Research Institute for Global Change
JAMSTEC  Japan Agency for Marine-Earth Science and Technology
GO-SHIP  Global Ocean Ship-Based Hydrographic Investigation Program
CCHDO    CLIVAR and Carbon Hydrographic Data Office
CDIAC    Carbon Dioxide Information Analysis Center






1  Cruise Narrative

   Akihiko Murata (RIGC/JAMSTEC)
   Yuichiro Kumamoto (RIGC/JAMSTEC)

1.1  Highlight

GHPO Section Designation: P10

Cruise code: MR11-08

Expedition Designation: 49NZ20111220
                        49NZ20120113

Chief Scientists and Affiliation:

    Leg 2: Akihiko Murata
           murataa@jamstec.go.jp

    Leg 3: Yuichiro Kumamoto
           kumamoto@jamstec.go.jp

           Ocean Climate Change Research Program
           Research Institute for Global Change (RIGC)
           Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
           2-15 Natsushima, Yokosuka, Kanagawa, Japan 237-0061
           Fax: +81-46-867-9835

Ship: R/V Mirai

Ports of Call: Leg 2: Koror, Palau – Guam, USA
               Leg 3: Guam, USA – Sekinehama, Japan

Cruise Dates: Leg 2: December 20, 2011 – January 12, 2012
              Leg 3: January 13, 2012 – February 9, 2012

Number of Stations: 102 stations for CTD/Carousel Water Sampler
                    (Leg 2: 59, Leg 3: 43)

Geographic Boundaries (for hydrographic stations):
               10ºS -  43ºN
              140ºE - 151ºE

Floats and Drifters Deployed:

     2 Argo floats

Mooring Deployed or Recovered Mooring:

     None

 
1.2  Cruise Summary

It is well known that climate changes of a timescale more than a decade are 
influenced by changes of oceanic conditions. Among various oceanic changes, 
we conducted shipboard observations focusing on storage and transport of 
anthropogenic CO2, heat and freshwater in the ocean, which are important for 
global warming and relevant climate changes. Our observation line (Figs. 
1.2.1 and 1.2.2) is a meridional line, which is set in the western Pacific, 
and traverses the main subtropical gyre in the ocean. By occupying the 
observation line, we intended to clarify: (1) storage of anthropogenic CO2, 
distributions of dissolved oxygen, etc. in the subtropical gyre and the 
temporal changes, (2) temperature rise and transport of dissolved substances 
along the route of Circumpolar Deep Water, and (3) current degree of ocean 
acidification in the western Pacific. This study was conducted under the 
Global Ocean Ship-based Hydrographic Investigations Program (abbreviated as 
GO-SHIP, http://www.go-ship.org/).

In addition to the objectives listed above, we were also aimed at elucidating 
dispersion of radioactive substances, released into the sea unfortunately 
from the Fukushima Dai-ichi nuclear power plant.

During the 2nd leg, we could conduct hydrographic observations steadily. But 
during the 3rd leg, we had to give up some hydrographic casts due to big 
waves.

Figure 1.2.1: Cruise track and hydrographic stations.
Figure 1.2.2: Bottle depth diagram.

 
1.3  List of Principal Investigator 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: List of principal investigator and person in charge on the ship.

Item           Principal Investigator            Person in Charge on the Ship
-------------  --------------------------------  ------------------------------

Underway

ADCP           Shinya Kouketsu (JAMSTEC)         Kazuho Yoshida (GODI) (leg 2)
               skouketsu@jamstec.go.jp           Katsuhisa Maeno (GODI) (lge 3)



Bathymetry     Takeshi Matsumoto (U of Ryukyus)  Kazuho Yoshida (GODI) (leg 2)
               tak@sci.u-ryukyu.ac.jp            Katsuhisa Maeno (GODI) (leg 3)
               Naoto Hirano (Tohoku Univ.)
               nhirano@cneas.tohoku.ac.jp

Meteorology    Kunio Yoneyama (JAMSTEC)          Kazuho Yoshida (GODI) (leg 2)
               yoneyamak@jamstec.go.jp           Katsuhisa Maeno (GODI) (leg 3)

T-S            Hiroshi Uchida (JAMSTEC)          Miyo Ikeda (MWJ) (leg 2)
               huchida@jamtec.go.jp              Misato Kuwahara (MWJ) (leg 3)

pCO2           Akihiko Murata (JAMSTEC)          Yoshiko Ishikawa (MWJ)
               murataa@jamstec.go.jp


Hydrography

CTD/O2         Hiroshi Uchida (JAMSTEC)          Shinsuke Toyoda (MWJ) (leg 2)
               huchida@jamstec.go.jp             Kenichi Katayama (MWJ) (leg 3)

XCTD           Hiroshi Uchida (JAMSTEC)          Katsuhisa Maeno (GODI)
               huchida@jamstec.go.jp


LADCP          Shinya Kouketsu (JAMSTEC)         Shinya Kouketsu (JAMSTEC) (leg 2)
               skouketsu@jamstec.go.jp           Katsuro Katsumata (JAMSTEC) (leg 3)

Salinity       Hiroshi Uchida (JAMSTEC)          Fujio Kobayashi (MWJ) (leg 2)
               huchida@jamstec.go.jp             Tatsuya Tanaka (MWJ) (leg 3)

Density        Hiroshi Uchida (JAMSTEC)          Hiroshi Uchida (JAMSTEC)
               huchida@jamstec.go.jp


Oxygen         Yuichiro Kumamoto (JAMSTEC)       Miyo Ikeda (MWJ) (leg 2)
               kumamoto@jamstec.go.jp            Misato Kuwahara (MWJ) (leg 3)

Nutrients      Michio Aoyama (MRI)               Minoru Kamata (MWJ)
               maoyama@mri-jma.go.jp

DIC            Akihiko Murata (JAMSTEC)          Yoshiko Ishikawa (MWJ)
               murataa@jamstec.go.jp


Alkalinity     Akihiko Murata (JAMSTEC)          Tomonori Watai (MWJ)
               murataa@jamstec.go.jp

pH             Akihiko Murata (JAMSTEC)          Tomonori Watai (MWJ)
               murataa@jamstec.go.jp

CFCs           Ken’ichi Sasaki (JAMSTEC)         Ken’ichi Sasaki (JAMSTEC)
               ksasaki@jamstec.go.jp

Δ14C/δ13C      Yuichiro Kumamoto (JAMSTEC)       Yuichiro Kumamoto (JAMSTEC)
               kumamoto@jamstec.go.jp

134Cs/137Cs    Yuichiro Kumamoto (JAMSTEC)       Yuichiro Kumamoto (JAMSTEC)
               kumamoto@jamstec.go.jp

Tritium        Tatsuo Aono (NIRS)
               t_aono@nirs.go.jp

Iodine-129     Shigeyoshi Otosaka (JAEA)
               otosaka.shigeyoshi@jaea.go.jp

Chlorophyll a  Osamu Yoshida (RGU)               Osamu Yoshida (RGU) (leg 2)
               yoshida@rakuno.ac.jp              Hiroshi Uchida (JAMSTEC) (leg 3)
               Hiroshi Uchida (JAMSTEC)
               huchida@jamstec.go.jp

N2O/CH4        Osamu Yoshida (RGU)               Osamu Yoshida (RGU) (leg 2)
               yoshida@rakuno.ac.jp              Yuki Okazaki (RGU) (leg 3)

PFCs           Nobuyasu Yamashita (AIST)
               nob.yamashita@aist.go.jp

Plankton       Minoru Kitamura (JAMSTEC)         Minoru Kitamura (JAMSTEC)
               kitamura@jamstec.go.jp


Floats

ARGO float     Toshio Suga (JAMSTEC)             Kenichi Katayama (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.
     NIRS     National Institute of Radiological Sciences
     JAEA     Japan Atomic Energy Agency
     RGU      Rakuno Gakuen University
     AIST     National Institute of Advanced Industrial Science and Technology


1.4  List of Cruise Participants


Table 1.4.1: List of cruise participants for leg 2.

Name                 Responsibility                              Affiliation
-------------------  ------------------------------------------  ------------
Akihiko Murata       Chief Scientist/CTD/water sampling          RIGC/JAMSTEC
Yuichiro Kumamoto    DO/radionuclides                            RIGC/JAMSTEC
Hiroshi Uchida       CTD/density/water sampling                  RIGC/JAMSTEC
Shinya Kouketsu      LADCP/ADCP/water sampling                   RIGC/JAMSTEC
Kazuhiko Hayashi     Water sampling                              RIGC/JAMSTEC
Ken’ichi Sasaki      CFCs                                        MIO/JAMSTEC
Moyap Kilepak        Observer                                    U. of PNG
Benjamin Malai       Observer                                    NWS/PNG
Osamu Yoshida        CH4 and N2O/water sampling                  RGU
Yuki Okazaki         CH4 and N2O/water sampling                  RGU
Shinichi Oikawa      CH4 and N2O/water sampling                  RGU
Hikari Shimizu       CH4 and N2O/water sampling                  RGU
Satoshi Ozawa        Chief technologist/CTD/water sampling       MWJ
Hirokatsu Uno        CTD/water sampling                          MWJ
Fujio Kobayashi      Salinity                                    MWJ
Kenichi Kato         CTD/water sampling                          MWJ
Shinsuke Toyoda      CTD/water sampling                          MWJ
Hiroki Ushiromura    Salinity                                    MWJ
Shungo Oshitani      CTD/water sampling                          MWJ
Kenichiro Sato       Nutrients                                   MWJ
Minoru Kamata        Nutrients                                   MWJ
Masanori Enoki       Nutrients                                   MWJ
Tomonori Watai       pH/total alkalinity                         MWJ
Yoshiko Ishikawa     DIC/pCO2                                    MWJ
Miyo Ikeda           DO                                          MWJ
Ayaka Hatsuyama      pH/total alkalinity                         MWJ
Hatsumi Aoyama       DIC/pCO2                                    MWJ
Masahiro Orui        CFCs                                        MWJ
Makoto Takada        Water sampling/radionuclides                MWJ
Katsunori Sagishima  CFCs                                        MWJ
Shoko Tatamisashi    CFCs                                        MWJ
Kanako Yoshida       DO                                          MWJ
Yuki Miyajima        DO                                          MWJ
Elena Hayashi        Water sampling                              MWJ
Tatsuya Ando         Water sampling                              MWJ
Hitomi Takahashi     Water sampling                              MWJ
Mizuho Yasui         Water sampling                              MWJ
Daiki Hayashi        Water sampling                              MWJ
Yusuke Ogiwara       Water sampling                              MWJ
Satoshi Okumura      Chief technologist /meteorology/
                     geophysics/ADCP/XCTD                        GODI
Kazuho Yoshida       Meteorology/geophysics/ADCP/XCTD            GODI
Ryo Kimura           Meteorology/geophysics/ADCP/XCTD            GODI

     GODI     Global Ocean Development Inc.
     JAMSTEC  Japan Agency for Marine-Earth Science and Technology
     RIGC     Research Institute for Global Change
     MIO      Mutsu Institute of Oceanography
     MWJ      Marine Works Japan, Ltd.
     RGU      Rakuno Gakuen University
     PNG      Papua New Guinea
     NWS      National Weather Service


Table 1.4.2: List of cruise participants for leg 3.

Name                 Responsibility                              Affiliation

Yuichiro Kumamoto    Chief scientist/DO/radionuclides            RIGC/JAMSTEC
Hiroshi Uchida       CTD/density/water sampling RIGC/JAMSTEC
Katsuro Katsumata    XMP/LADCP/water sampling RIGC/JAMSTEC
Toshimasa Doi        LADCP/water sampling RIGC/JAMSTEC
Kazuhiko Hayashi     Water sampling RIGC/JAMSTEC
Ken’ichi Sasaki      CFCs MIO/JAMSTEC
Minoru Kitamura      Plankton BGS/JAMSTEC
Eric Cruz            Plankton net dragging/water sampling NMFS/NOAA
Nobuyoshi Yamashita  PFCs AIST
Yuki Okazaki         CH4 and N2O/water sampling RGU
Shinichi Oikawa      CH4 and N2O/water sampling RGU
Hikari Shimizu       CH4 and N2O/water sampling RGU
Yoshiko Ishikawa     Chief technologist /DIC/pCO2 MWJ
Hideki Yamamoto      Water sampling/radionuclides MWJ
Toru Idai            CTD/water sampling MWJ
Kenichi Katayama     CTD/water sampling MWJ
Naoko Miyamoto       CTD/water sampling MWJ
Tatsuya Tanaka       Salinity MWJ
Tamami Ueno          Salinity MWJ
Kenichiro Sato       Nutrients MWJ
Minoru Kamata        Nutrients MWJ
Tomonori Watai       pH/total alkalinity MWJ
Yasuhiro Arii        Nutrients MWJ
Misato Kuwahara      DO MWJ
Hatsumi Aoyama       DIC/pCO2 MWJ
Makoto Takada        DIC/pCO2 MWJ
Shinichiro Yokokawa  DO MWJ
Katsunori Sagishima  CFCs MWJ
Shoko Tatamisashi    CFCs MWJ
Hironori Sato        DO MWJ
Kanako Yoshida       DO MWJ
Takami Mori          CTD/water sampling MWJ
Yasumi Yamada        pH/total alkalinity MWJ
Elena Hayashi        Water sampling MWJ
Tatsuya Ando         Water sampling MWJ
Rie Muranaka         Water sampling MWJ
Shihomi Saito        Water sampling MWJ
Emi Deguchi          Water sampling MWJ
Erina Matsumoto      Water sampling MWJ
Katsuhisa Maeno      Chief technologist /meteorology/            GODI
                     geophysics/ADCP/XCTD
Asuka Doi            Meteorology/geophysics/ADCP/XCTD            GODI
Kazuho Yoshida       Meteorology/geophysics/ADCP/XCTD            GODI
Toshimitsu Goto      Meteorology/geophysics/ADCP/XCTD            GODI

     BGS        Institute of Biogeosciences
     NMFS/NOAA  National Marine Fisheries Service, National Oceanic and 
                Atmospheric Administration




2  UNDERWAY MEASUREMENTS

2.1  Navigation
     February 5, 2014

(1) Personnel

     Kazuho Yoshida   (GODI)       -leg1, leg2-
     Ryo Kimura       (GODI)       -leg1, leg2-
     Satoshi Okumura  (GODI)       -leg2-
     Katsuhisa Maeno  (GODI)       -leg3-
     Asuka Doi        (GODI)       -leg3-
     Toshimitsu Goto  (GODI)       -leg3-
     Ryo Ohyama       (MIRAI Crew) -leg1, leg2, leg3-

(2) System description

Ship’s position and velocity were provided by Radio Navigation System on R/V 
Mirai. This system integrates GPS position, log speed, gyro compass heading 
and other basic data for navigation, and calculated speed/course over ground 
on workstation. Radio navigation System also distributed ship’s standard time 
synchronized to GPS time server via Network Time Protocol. These data were 
logged on the network server as “SOJ” data every 5 seconds.

Sensors for navigation data are listed below;

  i) GPS system: MultiFix6 (software version 1.01), Differential GPS system.

     Receiver: Trimble SPS751, with two GPS antennas located on navigation 
     deck, starboard side and port side, manually switched as to GPS 
     receiving state and offset to radar-mast position, datum point.

     Decoder: Fugro STARFIX 4100LR

 ii) Doppler log: Furuno DS-30, which use three acoustic beam for current 
     measurement under the hull.

iii) Gyrocompass: Tokimec TG-6000, sperry type mechanical gyrocompass.

 iv) GPS time server: SEIKO TS-2540 Time Server, synchronizing to GPS 
     satellite every 1 second.

(3) Data period (Times in UTC)

    Leg1: 04:50 4th Dec. 2011 to 00:00 20th Dec. 2011
    Leg2: 06:00 20th Dec. 2011 to 02:00 12th Jan. 2012
    Leg3: 23:00 12th Jan. 2012 to 00:00 9th Feb. 2012

Figure 2.1.1: Cruise Track of MR11-08 Leg 1.
Figure 2.1.2: Cruise Track of MR11-08 Leg 2.
Figure 2.1.3: Cruise Track of MR11-08 Leg 3.


2.2  Swath Bathymetry
     February 5, 2014

(1) Personnel

    Takeshi Matsumoto (U. of the Ryukyu):   Principal Investigator 
                                            (Not on-board)
    Naoto Hirano      (Tohoku U.):          Principal Investigator 
                                            (Not on-board)
    Kazuho Yoshida    (GODI)                -leg1, leg2-
    Ryo Kimura        (GODI)                -leg1, leg2-
    Satoshi Okumura   (GODI)                -leg2-
    Katsuhisa Maeno   (GODI)                -leg3-
    Asuka Doi         (GODI)                -leg3-
    Toshimitsu Goto   (GODI)                -leg3-
    Ryo Ohyama        (MIRAI Crew)          -leg1, leg2, leg3-
    
(2) Introduction

R/V MIRAI is equipped with a Multi narrow Beam Echo Sounding system (MBES), 
SEABEAM 2112 (SeaBeam Instruments Inc.). The objective of MBES is collecting 
continuous bathymetric data along ship’s track to make a contribution to 
geological and geophysical investigations and global datasets.

(3) Data acquisition

The “SEABEAM 2112” on R/V MIRAI was used for bathymetry mapping during the 
MR11-08 cruise from 4th December 2011 to 9th February 2012.

To get accurate sound velocity of water column for ray-path correction of 
acoustic multibeam, we used Surface Sound Velocimeter (SSV) data to get the 
sea surface (6.2m) sound velocity, and the deeper depth sound velocity 
profiles were calculated by temperature and salinity profiles from CTD or 
XCTD or ARGO data by the equation in Del Grosso (1974) during the cruise.

Table 2.2.1 shows system configuration and performance of SEABEAM 2112.004 
system.


Table 2.2.1: System configuration and performance.

SEABEAM 2112 (12 kHz system)

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)

(4) Data processing

 i. Sound velocity correction

The continuous bathymetry data were split into small areas around each CTD 
station. For each small area, the bathymetry data were corrected with a sound 
velocity profile calculated from the CTD data or XCTD data in the area. The 
equation of Del Grosso (1974) was used for calculating sound velocity. The 
data processing is carried out using “mbprocess” command of MBsystem.

ii. Editing and Gridding

Gridding for the bathymetry data were carried out using the HIPS software 
version 7.1 (CARIS, Canada). Firstly, the bathymetry data during Ship’s 
turning was basically removed before “BASE surface” was made. A spike noise 
of each swath data was also removed using “swath editor” and “subset editor”. 
Then the bathymetry data was gridded by “Interpolate” function of the 
software with the parameters shown as Table 2.2.2.

Finally, raw data and interpolated data are exported as ASCII data, and 
converted to 150m grid data using “xyz2grd” utility of GMT (Generic Mapping 
Tool) software.

Table 2.2.2: Parameters for interpolate of bathymetry data.

           BASE surface resolution:                     50m
           Interpolate matrix size:                     5 x 5
           Minimum number of neighbors for interpolate: 10

(5) Data archives

Bathymetric data obtained during this cruise will be submitted to the Data 
Management Group (DMG) of JAMSTEC, and will be archived there.

(6) Remarks (Times in UTC)

    1) The observation was carried out within following periods,
       Leg1: 10:00 5th Dec. 2011 to 08:30 10th Dec.2011
       Leg2: 22:10 21th Dec. 2011 to 00:00 22th Dec. 2011
             19:30 23th Dec. 2011 to 04:30 1st Jan. 2012
             14:00 3rd Jan 2012 to 14:09 12th Jan. 2012
       Leg3: 02:48 13th Jan. 2012 to 05:13 06th Feb 2012.

2) The following period, data acquisition was suspended due to system trouble 
   and network trouble.
             15:27 to 18:22 8th  Dec. 2011
             21:00 to 21:37 20th Dec. 2011
             08:10 to 08:34 10th Jan. 2012
             21:35 to 22:03 22th Jan. 2012
             15:48 to 16:15 31th Jan. 2012

3) The following period, GPS data acquisition was suspended due to GPS 
   trouble.
             03:39 to 03:52 3rd Feb. 2012


2.3  Surface Meteorological Observation
     January 25, 2014

(1) Personnel
 
    Kunio Yoneyama (JAMSTEC)
    Kasuo Yoshida (GODI) (Legs 1, 2)
    Ryo Kimura (GODI) (Legs 1, 2)
    Satoshi Okumura (GODI) (Leg 2)
    Katsuhisa Maeno (GODI) (Leg 3)
    Asuka Doi (GODI) (Leg 3)
    Toshimitsu Goto (GODI) (Leg 3)
    Ryo Ohyama (Mirai Crew) (Legs 1, 2, 3)

(2) Objective

As basic information about general weather conditions during the cruise, 
surface meteorological observation had been continuously conducted.

(3) Methods

There are two different surface meteorological observation systems onboard 
the R/V MIRAI. One is the MIRAI surface meteorological measurement station 
(SMET), and the other is the Shipboard Oceanographic and Atmospheric 
Radiation (SOAR) system.

Instruments of SMET whose data are used here are listed in Table 2.3.1. All 
SMET data were collected 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 low starting threshold wind speed (1 m/sec) 
comparing to SMET’s (2m/sec), and 3) SMET’s radiometers has 10 W/m2 
resolution, while SOAR takes 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. 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), that has been 
developed by the U.S. National Oceanic and Atmospheric Administration (NOAA) 
for data collection, management, real-time monitoring, etc. Information on 
sensors used here is listed in Table 2.3.2.


Table 2.3.1: Instruments and locations of SMET.

Sensor         Parameter          Manufacturer/type        Location/height from sea level
-------------  -----------------  -----------------------  ------------------------------
Thermometer*1  air temperature    Vaisala, Finland/HMP45A  compass deck*2 / 21 m
               relative humidity

Thermometer    sea temperature    SBE, USA/SBE-3S          bow thruster room / -5 m

Barometer      pressure           Setra System, USA/       captain deck / 13 m
                                  Model-370

  *1: Gill aspirated radiation shield 43408 made by R. M. Young, USA is attached.
  *2: Thermometers are equipped at both starboard and port sides, and upwind-side data 
      are used.


Table 2.3.2: Instruments and locations of SOAR.

Sensor         Parameter          Manufacturer/type        Location/height from sea level
-------------  -----------------  -----------------------  ------------------------------
Anemometer     Wind speed/        R.M. Young, USA/05106    Foremast / 25 m
                 direction

Rain gauge     Rainfall           R.M. Young, USA/50202    Foremast / 24 m
                 accumulation

Radiometer     Short wave         Eppley, USA/PSP          Foremast / 25 m
                 radiation        
               Long wave          Eppley, USA/PIR          Foremast / 25 m
                 radiation



(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 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 4 minutes. Since the thermometers are equipped on both 
starboard/port sides, we adopted air temperature/ relative humidity data 
taken at upwind side. Dew point temperature was calculated 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 contain the 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), shortwave and longwave radiation (W/m2).

Missing values are expressed as “9999”.



(5) Data quality

To ensure the data quality, each sensor was calibrated as follows. It is 
remarked, however, since there is a possibility that data may contain noises 
caused by turbulence, it is recommended to filter out such data by using 
smoothed data (e.g., 1-hour mean) from this 1-minute mean data sets depending 
on the scientific purpose.

T/RH sensor;

Temperature and humidity probes were calibrated before (Aug. 3, 2011) and 
after (Feb. 28, 2012) the cruise by the manufacturer. Certificated accuracy 
for 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 each cruise. The results are listed below.


  Check date                                   Dec. 01, 2011  Feb. 10, 2012
  -------------------------------------------------------------------------
  Temperature (˚C)  Port side       SMET       27.6           –5.7
                                    Portable   27.9           –5.6
                    Starboard side  SMET       27.9           –5.1
                                    Portable   27.9           –5.0
  Relative          Port side       SMET       76.9           62.1
    Humidity (%)                    Portable   74.0           61.7
                    Starboard side  SMET       78.1           66.0
                                    Portable   76.2           62.1


Pressure sensor;

Using calibrated portable barometer (Vaisala, Finland / PTB220), pressure 
sensor was checked before/after the cruise. Accuracy is better than ±0.2 hPa.


      Check date       Oct.26       Dec.01       Feb.10         Mar.30
      -----------------------------------------------------------------
      SMET             1007.45      1008.06      1013.52        1016.51
      Reference        1007.43      1008.00      1013.64        1016.40
      Difference         +0.02        +0.06        –0.12           0.11
      


Precipitation;

Prior to the cruise, we put the water into the rain gauge to check their 
linearity between the indicated values and actual water amount input. 
Expected accuracy is better than ± 1mm which corresponds to sensor’s
original specification.


Calibration date   Dec. 2(1)   Dec. 2(2)   Dec. 2(3)   Feb. 9(1)   Feb. 9(2)   Feb. 9(3)
----------------------------------------------------------------------------------------
Min input water      0.00        0.00        0.00        0.00        0.00        0.00
  volume (cc)
Min measured         0.13        0.11        0.12        0.47        0.47        0.53
  value (mm)
Max input water    505.00      504.50      502.50      504.50      506.50      506.00
  volume (cc)
Max measured        49.28       49.25       49.28       50.10       50.21       50.29
  value (mm)

Radiation sensors;

Short wave and long wave radiometers were calibrated by Remote Measurement & 
Research Company with the help of Department of Energy, Atmospheric Radiation 
Measurement Program prior to the cruise. Sensors used here were calibrated on 
June 3, 2011.

    For PSP; y = 3.691x + 4.2

    For PIR; y = 1.252x – 23.3,

where y = Insolation (W/m2), and x = ADC value (mV).

1/(T+T0) = P1 a3 + P2 a2 + P3 a + P4, where a = ln(ADC mV), and T0 = 273.15 K

Case temperature fit; max error = 0.000 ˚C

    P1 = 3.0273e–6, P2 = –3.6335e–5, P3 = 4.2203e–4, P4 = 1.7194e–3

Dome temperature fit; max error = 0.000 ˚C

    P1 = 3.0297e–6, P2 = –3.6490e–5, P3 = 4.2347e–4, P4 = 1.7153e–3


(6) Data periods

    Leg-1: December 05, 2011, 1001Z – December 10, 2011, 0829Z

    Leg-2: December 20, 2011, 2101Z – December 22, 2011, 0000Z
           December 23, 2011, 1931Z – January 01,  2012, 0429Z
           January  03, 2012, 1401Z – January 10,  2012, 1400Z

    Leg-3: January  13, 2012, 0246Z – February 09, 2012, 0900Z


(7) Preliminary results

Figures 2.3.1, 2.3.2 and 2.3.3 show the time series of surface meteorological 
observation for each cruise. One hour mean values (time stamp at the medium 
of the average) instead of 1 minute mean are used to depict these figures.


Figure 2.3.1: Time series of (a) air and sea surface temperature, (b) 
              relative humidity, (c) precipitation, (d) pressure, (e) zonal 
              and meridional wind components, and (e) short and long wave 
              radiation for the Leg-1 cruise. Day-330 corresponds to Nov. 26, 
              2011.

Figure 2.3.2: Same as Fig. 2.3.1, but for the Leg-2 cruise. Day-350 
              corresponds to Dec. 16, 2011.

Figure 2.3.3: Same as Fig. 2.3.1, but for the Leg-3 cruise. Vertical scale 
              for (a) and (d) are also different with Fig. 2.3.1. Day-10 
              corresponds to Jan. 10, 2012.



2.4  Thermo-Salinograph and Related Measurements
     February 4, 2014


(1) Personnel

    Hiroshi Uchida (JAMSTEC)
    Miyo Ikeda (MWJ) (Leg 2)
    Kanako Yoshida (MWJ) (Leg 2, 3)
    Yuki Miyajima (MWJ) (Leg 2)
    Misato Kuwahara (MWJ) (Leg 3)
    Shinichiro Yokogawa (MWJ) (Leg 3)


(2) Objectives

The objective is to collect sea surface salinity, temperature, dissolved 
oxygen, and fluorescence data continuously along the cruise track.


(3) Materials and methods

The Continuous Sea Surface Water Monitoring System (Marine Works Japan Co, 
Ltd.) has six sensors and automatically measures salinity, temperature, 
dissolved oxygen, and fluorescence in sea surface water every one minute. 
This system is located in the sea surface monitoring laboratory and connected 
to shipboard LAN system. Measured data along with time and location of the 
ship were displayed on a monitor and stored in a desktop computer. The sea 
surface water was continuously pumped up to the laboratory from about 5 m 
water depth and flowed into the system through a vinyl-chloride pipe. The 
flow rate of the surface seawater was controlled to be 5 dm3/min. 
Manufacturer’s specifications of the each sensor in this system are listed 
below.

 i. Software Seamoni-kun Ver.1.20

ii. Sensors

    Temperature and conductivity sensor

      Model: SBE-45,                 SEA-BIRD ELECTRONICS, INC.
      Serial number:                 4563325-0362 (leg 1)
                                     4557820-0319 (legs 2, 3)
      Measurement range:             Temperature –5 to 35ºC
                                     Conductivity 0 to 7 S m–1
      Initial accuracy:              Temperature 0.002ºC
                                     Conductivity 0.0003 S m–1
      Typical stability (per month): Temperature 0.0002ºC
                                     Conductivity 0.0003 S m–1
      Resolution:                    Temperatures 0.0001ºC
                                     Conductivity 0.00001 S m–1

Bottom of ship thermometer

    Model:                           SBE 38, SEA-BIRD ELECTRONICS, INC.
    Serial number:                   3857820-0540
    Measurement range:               –5 to +35ºC
    Initial accuracy:                ±0.001ºC
    Typical stability (per 6 month): 0.001ºC
    Resolution:                      0.00025ºC

Dissolved oxygen sensor
    Model:                           OPTODE 3835, AANDERAA Instruments.
    Serial number:                   1519
    Measuring range:                 0 - 500 μmol L–1
    Resolution:                      <1 μmol L–1
    Accuracy:                        <8 μmol L–1 or 5%whichever is greater
    Settling time (63%):             <25 s

Fluorometer
    Model:                           C3, TURNER DESIGNS
    Serial number:                   2300123


(4) Data Processing and Quality Control

Data from the Continuous Sea Surface Water Monitoring System were processed 
as follows. Data gaps were linearly interpolated when the gap was ≤ 7 
minutes. Spikes in the temperature and salinity data were removed using a 
median filter with a window of 3 scans (3 minutes) when difference between 
the original data and the median filtered data was larger than 0.1 ºC for 
temperature and 0.5 for salinity. Fluorometer data were low-pass filtered 
using a median filter with a window of 3 scans (3 minutes) to remove spikes. 
Raw data from the OPTODE oxygen sensor and the fluorometer data were low-pass 
filtered using a Hamming filter with a window of 15 scans (15 minutes). 
Salinity (S [PSU]), dissolved oxygen (O [μmol/kg]) and fluorescence (Fl 
[RFU]) data were corrected using the water sampled data. Details of the 
measurement methods are described in Sections 3.2, 3.4, and 3.8 for salinity, 
dissolved oxygen and chlorophyll-a, respectively. Corrected salinity (Scor), 
dissolved oxygen (Ocor), and estimated chlorophyll a (Chl-a) were calculated 
from following equations

    Scor [PSU] =     c0 + c1 S + c2 t
    Ocor [μmol/kg] = c0 + c1 O + c2 T + c3 t
    Chl-a [μg/L]   = c0 + c1 Fl

where t is days from a reference time, T is temperature in ºC. The best fit 
sets of calibration coefficients (c0~c3) were determined by a least square 
technique to minimize the deviation from the water sampled data. The 
reference times were listed in Table 2.4.1. The calibration coefficients were 
listed in Table 2.4.2. Comparisons between the Continuous Sea Surface Water 
Monitoring System data and water sampled data are shown in from Figs. 2.4.1 
to 2.4.6. For leg 3, sensitivity of the fluorometer to chlorophyll a was 
different between subtropical region and subarctic region. Therefore, slope 
(c1) of the calibration coefficients was changed according to the temperature 
for each area (Table 2.4.2).


Table 2.4.1: Reference time used in the calibration equations for salinity 
             and dissolved oxygen.

                          Leg  Date Time   (UTC)
                          ---  ----------  -----
                          2    2011/12/20  21:00
                          3    2012/01/13  02:47


Table 2.4.2: Calibration coefficients for the salinity, dissolved oxygen, and 
             chlorophyll a.
  
                  Leg         c0          c1           c2              c3
                  ---   -------------  ---------  -------------  ------------
Salinity
                   2     1.012865e-02  0.9995585  7.254156e-04
                   3    -8.713569e-02  1.002669   5.683519e-04

Dissolved oxygen
                   2    11.34542       1.102664   -0.6163531      -1.981512e-02
                   3    36.55213       0.9906656  -0.738031       -0.1868786
Chlorophyll a
                   2     4.082381e-02  0.1021539
                   3     3.746690e-02  0.1262224 (for temperature < 17 ºC)
                         3.746690e-02  8.794529e-02 (for temperature ≥ 17 ºC)


Figure 2.4.1: Comparison between TSG salinity (red: before correction, green: 
              after correction) and sampled salinity for leg 2.

Figure 2.4.2: Same as Fig. 2.4.1, but for leg 3.

Figure 2.4.3: Comparison between TSG oxygen (red: before correction, green: 
              after correction) and sampled oxygen for leg 2.

Figure 2.4.4: Same as Fig. 2.4.3, but for leg 3.

Figure 2.4.5: Comparison between TSG fluorescence and sampled chlorophyll a 
              for leg 2. For bottom panel, red (temperature ≥ 17ºC) and blue 
              (temperature < 17ºC) dots indicate fluorescence and green dots   
              indicate water sampled chlorophyll a. Line indicates 
              chlorophyll a estimated from fluoremeter.

Figure 2.4.6: Same as Fig. 2.4.5, but for leg 3.



2.5 Underway pCO2
    24 September, 2013

(1) Personnel

    Akihiko Murata   (RIGC, JAMSTEC)
    Yoshiko Ishikawa (MWJ)
    Hatsumi Aoyama   (MWJ)
    Makoto Takada    (MWJ)


(2) Introduction

Concentrations of CO2 in the atmosphere are now increasing at a rate of 1.9 
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 P10 revisit cruise, we were aimed at quantifying how much 
anthropogenic CO2 is absorbed in the surface ocean in the western 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 nondispersive infrared gas 
analyzer (Li-COR LI-7000), 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 700 – 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 
400 – 500 ml min-1.

The CO2 measuring system was set to repeat the measurement cycle such as 4 
kinds of CO2 standard gases (Table 2.5.1), 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 2.5.1, which 
were calibrated after cruise by the JAMSTEC primary standard gases. The CO2 
concentrations of the primary standard gases were calibrated by the Scripps 
Institution of Oceanography, La Jolla, CA, USA.

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 Takahashi et al. (1993), 
although the temperature increases were slight, being ~0.3 °C.

We checked values of xCO2a and xCO2s by examining signals of the NDIR by 
plotting the xCO2a and xCO2s as a function of sequential day, longitude, sea 
surface temperature and sea surface salinity.



Reference

Takahashi, T., J. Olafsson, J. G. Goddard, D. W. Chipman, and S. C. 
    Southerland (1993): Seasonal variation of CO2 and nutrients in the high-
    latitude surface oceans: a comparative study, Global Biogeochem. Cycles, 
    7, 843 – 878.


Table 2.5.1: Concentrations of CO2 standard gases used during MR11–08 cruise.

                     Cylinder no.  Concentrations (ppmv)
                     ------------  ---------------------
                       CRC00049           270.13
                       CRC00046           330.29
                       CRC00047           360.28
                       CRC00048           420.25


2.6  Shipboard ADCP
     August 13, 2013

(1) Personnel

    Shinya Kouketsu (JAMSTEC): Principal Investigator
    Kazuho Yoshida  (Global Ocean Development Inc., GODI) -leg1, leg2-
    Ryo Kimura      (GODI)                                -leg1, leg2-
    Satoshi Okumura (GODI)                                      -leg2-
    Katsuhisa Maeno (GODI)                                            -leg3-
    Asuka Doi       (GODI)                                            -leg3-
    Toshimitsu Goto (GODI)                                            -leg3-
    Ryo Ohyama      (MIRAI Crew)                          -leg1, leg2, leg3-


(2) Objective

To obtain continuous measurement of the current profile along the ship’s 
track.


(3) Methods

Upper ocean current measurements were made in MR11-08 cruise, using the hull-
mounted Acoustic Doppler Current Profiler (ADCP) system. For most of its 
operation the instrument was configured for watertracking mode. Bottom-
tracking mode, interleaved bottom-ping with water-ping, was made to get the 
calibration data for evaluating transducer misalignment angle in the shallow 
water. The system consists of following components;

    1) R/V MIRAI has installed vessel-mount ADCP (75 kHz “Ocean Surveyor”, 
       Teledyne RD Instruments). It has a phased-array transducer with single 
       assembly and creates 4 acoustic beams electronically.

     2) For heading source, we use ship’s gyro compass (Tokimec, Japan), 
        continuously providing heading to the ADCP system directory. Also we 
        have Inertial Navigation System (PHINS, iXSEA) which provide high-
        precision heading and attitude information are stored in “.N2R” data 
        files.

    3) DGPS system (Trimble SPS751 & StarFixXP) providing position fixes.

    4) We used VmDas version 1.4.6 (TRDI) for data acquisition.

    5) To synchronize time stamp of pinging with GPS time, the clock of the 
       logging computer is adjusted to GPS time every 1 minute.

    6) The sound speed at the transducer does affect the vertical bin mapping 
       and vertical velocity measurement, is calculated from temperature, 
       salinity (constant value; 35.0 psu) and depth (6.5 m; transducer 
       depth) by equation in Medwin (1975).

Data were configured for 8-m intervals starting 19-m below the surface. Every 
ping was recorded as raw ensemble data (.ENR). Also, 60 seconds and 300 
seconds averaged data were recorded as short term average (.STA) and long 
term average (.LTA) data, respectively. Major parameters for the measurement 
(Direct Command) are shown in Table 2.6.1.

 
(4) Preliminary results

Figs.2.6.1, 2.6.2 and 2.6.3 shows surface current profile along the ship’s 
track, averaged four depth cells from the top, 23 m to 55 m with 30 minutes 
average. In the layer upper 300m, the velocity estimation were good during 
this cruise, because the echo intensities for each beams were over 60 counts 
at such depths (Fig. 2.6.4).

 
(5) Data

The processed data were fixed the ADCP misalignment by comparison between 
bottom track and ship velocities (based on GPS data) and were averaged over 
10 minutes. All the data obtained in this cruise will be submitted to the 
Data Management Group (DMG) of JAMSTEC, and will be opened to the public via 
JAMSTEC home page.


(6) Remarks (Times in UTC)

The observation was carried out within following periods

    Leg1: 10:00 5th Dec. 2011 to 08:30 10th Dec. 2011

    Leg2: 21:00 20th Dec. 2011 to 00:00 22th Dec. 2011
          19:30 23th Dec. 2011 to 04:30  1st Jan. 2012
          14:00 3rd  Jan. 2012 to 14:00 10th Jan. 2012
    Leg3: 02:45 13th Jan. 2012 to 00:00  9th Feb. 2012


Table 2.6.1. Major parameters.

Environmental Sensor Commands

    EA = +04500    Heading Alignment (1/100 deg)
    EB = +00000    Heading Bias (1/100 deg)
    ED = 00065     Transducer Depth (0 - 65535 dm)
    EF = +001      Pitch/Roll Divisor/Multiplier (pos/neg) [1/99 - 99]
    EH = 00000     Heading (1/100 deg)
    ES = 35        Salinity (0-40 pp thousand)
    EX = 00000     Coord Transform (Xform:Type; Tilts; 3Bm; Map)
    EZ = 10200010  Sensor Source (C; D; H; P; R; S; T; U)
                   C (1): Sound velocity calculates using ED, ES, ET (temp.)
                   D (0): Manual ED
                   H (2): External synchro
                   P (0), R (0): Manual EP, ER (0 degree)
                   S (0): Manual ES
                   T (1): Internal transducer sensor
                   U (0): Manual EU

Timing Commands

    TE = 00:00:02.00  Time per Ensemble (hrs:min:sec.sec/100)
    TP = 00:02.00     Time per Ping (min:sec.sec/100)
    
Water-Track Commands
    WA = 255          False Target Threshold (Max) (0-255 count)
    WB = 1            Mode 1 Bandwidth Control (0=Wid, 1=Med, 2=Nar)
    WC = 120          Low Correlation Threshold (0-255)
    WD = 111 100 000  Data Out (V; C; A; PG; St; Vsum; Vsum^2;#G;P0)
    WE = 1000         Error Velocity Threshold (0-5000 mm/s)
    WF = 0800         Blank After Transmit (cm)
    WG = 001          Percent Good Minimum (0-100%)
    WI = 0            Clip Data Past Bottom (0 = OFF, 1 = ON)
    WJ = 1            Rcvr Gain Select (0 = Low, 1 = High)
    WM = 1            Profiling Mode (1-8)
    WN = 100          Number of depth cells (1-128)
    WP = 00001        Pings per Ensemble (0-16384)
    WS = 0800         Depth Cell Size (cm)
    WT = 000          Transmit Length (cm) [0 = Bin Length]
    WV = 0390         Mode 1 Ambiguity Velocity (cm/s radial)


Figure 2.6.1: Current profile along the ship’s track, from 23m to 55m, 
              averaged every 30 minutes (Leg1).

Figure 2.6.2: Current profile along the ship’s track, from 23m to 55m, 
              averaged every 30 minutes (Leg2).

Figure 2.6.3: Current profile along the ship’s track, from 23m to 55m, 
              averaged every 30 minutes (Leg3).

Figure 2.6.4. Echo intensity.



2.7  XCTD
     February 5, 2014

(1) Personnel

    Hiroshi Uchida  (JAMSTEC)
    Katsuhisa Maeno (GODI)
    Ryo Ohyama      (GODI)
    Asuka Doi       (GODI)
    Toshimitsu Goto (GODI)


(2) Objectives

In this cruise, XCTD (eXpendable Conductivity, Temperature and Depth 
profiler) measurements were carried out to evaluate the fall rate equation 
and temperature by comparing with CTD (Conductivity, Temperature and Depth 
profiler) measurements, and to substitute for CTD measurements.

 
(3) Instrument and Method

The XCTDs used were XCTD-2 (Tsurumi-Seiki Co., Ltd., Yokohama, Kanagawa, 
Japan) with an MK-150N deck unit (Tsurumi-Seiki Co., Ltd.). The 
manufacturer’s specifications are listed in Table 2.7.1. In this cruise, the 
XCTD probes were deployed by using 8-loading automatic launcher (stations 64, 
67, 89_1, 89_2, 91, 93, 95, 103 and 105) or hand launcher (Tsurumi-Seiki Co., 
Ltd.). For comparison with CTD, XCTD was deployed at about 10 minutes after 
the beginning of the down cast of the CTD (stations 64, 67, 110, 112).


(4) Data Processing and Quality Control

The XCTD data were processed and quality controlled based on a method by 
Uchida et al. (2011). Depth error of the XCTD data was corrected by using the 
estimated terminal velocity error (–0.0362 m s–1) (Fig. 2.7.1). Mean thermal 
bias (+0.014 °C) of the XCTD data was estimated by comparing with the CTD 
data and corrected (Fig. 2.7.2). Salinity biases of the XCTD data were 
estimated by using temperature and salinity relationships in the deep ocean 
obtained from the post-cruise calibrated CTD data (Table 2.7.2). For the XCTD 
data of the station P10N_89_1~4 and P10N_113_1, salinity bias could not be 
estimated because the maximum depth was too shallow to estimate the salinity 
bias.

The temperature and salinity relationships in the deep ocean obtained from 
the post-cruise calibrated CTD and XCTD data were shown in Fig. 2.7.3.

 
References

Kizu, S., H. Onishi, T. Suga, K. Hanawa, T. Watanabe, and H. Iwamiya (2008): 
    Evaluation of the fall rates of the present and developmental XCTDs. 
    Deep-Sea Res I, 55, 571–586.

Uchida, H., K. Shimada, and T. Kawano (2011): A method for data processing to 
    obtain high quality XCTD data. J. Atmos. Oceanic Technol., accepted.


Table 2.7.1: Manufacturer’s specifications of XCTD-2.

  Parameter              Range                        Accuracy
  -------------  -----------------------  ---------------------------------
  Conductivity   0 ~ 60 mS cm–1           ±0.03 mS cm–1
  Temperature   –2 ~ 35 °C                ±0.02 °C
  Depth          0 ~ 1850 m (for XCTD-2)  5 m or 2%, whichever is greater *

* Depth error is shown in Kizu et al (2008).


Table 2.7.2: Serial number of the XCTD. Water depth, ship intake temperature 
             (SST) and salinity (SSS; not corrected), and maximum pressure 
             for the XCTD data are shown. Salinity offset applied to the XCTD  
             data and reference salinity estimated from the CTD data are also 
             shown.
  
Station  Serial number  Depth   SST     SSS    Max       Salinity  Reference salinity
                        [m]     [°C]    [PSU]  pressure  offset    [PSU]
                                               [dbar]    [PSU]
-------  -------------  -----  ------  ------  --------  --------  ------------------
  64_1     11022006     5714   25.045  35.045    2018     0.025     34.6081 @ 2.1°C
  67_3     11022005     5786   23.895  35.178    2018     0.022     34.6017 @ 2.0°C
  89_1     11022004     6145   17.866  34.717    889        –              NA
  89_2     11022001     6078   17.788  34.715    655        –              NA
  89_3     11021998     6130   17.797  34.717    823        –              NA
  89_4     11022002     6134   17.857  34.717    846        –              NA
  91_1     11021999     6067   12.769  34.303    2021    -0.002     34.5834 @ 2.0°C
  93_1     11021995     5778   14.356  34.513    2021     0.008     34.5834 @ 2.0°C
  95_1     11021996     5711   12.258  34.315    2021     0.008     34.5834 @ 2.0°C
  97_1     11021849     5622   15.091  34.592    1999     0.004     34.5834 @ 2.0°C
  99_1     11021850     5555   10.229  34.184    2021    -0.009     34.5834 @ 2.0°C
 101_1     11021851     5450   10.151  34.189    2011     0.005     34.5834 @ 2.0°C
 103_1     11022000     5300    9.662  34.128    2021     0.005     34.5834 @ 2.0°C
 105_1     11021846     5276    4.441  33.353    2022     0.025     34.5834 @ 2.0°C
 107_1     11021848     5817    4.642  33.409    2022     0.005     34.5834 @ 2.0°C
 108_1     11021847     6224    3.454  33.329    2016     0.019     34.5834 @ 2.0°C
 109_1     11021844     6321    3.415  33.325    2020     0.015     34.5834 @ 2.0°C
 110_2     11021843     4057    4.001  33.409    2022     0.018     34.5834 @ 2.0°C
 111_1     11021840     2695    3.810  33.370    2022     0.034     34.5834 @ 2.0°C
 112_1     11021841     1481    1.748  33.157    1475     0.010     34.4829 @ 2.4°C
 113_1     11021842     1047    0.501  32.511    1051       –              NA


Figure 2.7.1: Differences between XCTD and CTD depths for stations 64, 67, 
              110 and 112. Differences were estimated with the same method as 
              Uchida et al. (2011). Standard deviation of the estimates 
              (horizontal bars) and the manufacturer’s specification for XCTD 
              depth error (dotted lines) are shown. The regression for the 
              XCTD-2 data obtained in this cruise (black line) and for the 
              XCTD-2 data obtained in the MR09-01 cruise (red line) are 
              shown.

Figure 2.7.2: Comparison between XCTD and CTD temperature profiles. (a) Mean 
              temperature profile of CTD profiles (thick line) with standard 
              deviation (shade). (b) Mean temperature difference (thick line) 
              with standard deviation (shade) between the XCTD and CTD.

Figure 2.7.3: Comparison of temperature-salinity profiles of post-cruise 
              calibrated CTD (red lines) and XCTD (black lines).



3  Hydrographic Measurement Techniques and Calibrations

3.1  CTDO2 Measurements
     February 10, 2014

     (1) Personnel

         Hiroshi Uchida   (JAMSTEC)
         Shinsuke Toyoda  (MWJ) (Leg 2)
         Hirokatsu Uno    (MWJ) (Leg 2)
         Shungo Oshitani  (MWJ) (Leg 2)
         Kenichi Kato     (MWJ) (Leg 2)
         Satoshi Ozawa    (MWJ) (Leg 2)
         Kenichi Katayama (MWJ) (Leg 3)
         Toru Idai        (MWJ) (Leg 3)
         Naoko Miyamoto   (MWJ) (Leg 3)
         Takami Mori      (MWJ) (Leg 3)


(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 (Rochester 
Wire & Cable).

 
(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), two oxygen optodes (RINKO-III; JFE Alec Co., 
Ltd, Kobe Hyogo, Japan), a fluorometer (Seapoint sensors, Inc., Kingston, New 
Hampshire, USA), a transmissometer (C-Star Transmissometer; WET Labs, Inc., 
Philomath, Oregon, USA), and a Photosynthetically Active Radiation (PAR) 
sensor (Satlantic, LP, Halifax, Nova Scotia, Canada) were also used with the 
SBE 9plus underwater unit. 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 x 90 cm).

An additional set of SBE 911plus CTD system with 12-position SBE 32 was also 
used for three deep casts (P10N 90_2, 92_1, and 94_1) in leg 3, because 
tension of the winch exceeded the load capacity (3 ton) of the winch system 
at the CTD depths deeper than 5700 dbar, although tension of the winch had 
not exceeded the load capacity for the maximum depth of the CTD (6500 dbar) 
before the calibration of the tension meter performed in April 2011. The SBE 
9plus was mounted horizontally in a 12-position carousel frame.


Summary of the system used in this cruise

36-position CWS system (Set 1)

Deck unit:

    SBE 11plus, S/N 0272

Under water unit:

    SBE 9plus, S/N 117457 (Pressure sensor: S/N 1027)

Temperature sensor:

    SBE 3plus, S/N 4815 (primary)
    SBE 3plus, S/N 5329 (secondary, leg 2)
    SBE 3plus, S/N 4811 (secondary, leg 3)

Conductivity sensor:

    SBE 4, S/N 2854 (primary)
    SBE 4, S/N 3036 (secondary)

Oxygen sensor:

    SBE 43, S/N 0394
    JFE Advantech RINKO-III, S/N 0024 (foil batch no. 144002A)
    JFE Advantech RINKO-III, S/N 0079 (foil batch no. 160002A)

Pump:

    SBE 5T, S/N 4598 (primary)
    SBE 5T, S/N 4595 (secondary)

Altimeter:

    PSA-916T, S/N 1100 (leg 2)
    PSA-916T, S/N 1157 (leg 3)

Deep Ocean Standards Thermometer:

    SBE 35, S/N 0045

Fluorometer:

    Seapoint Sensors, Inc., S/N 3054

Transmissometer:

    C-Star, S/N CST-1363DR

PAR:

    Satlantic LP, S/N 0049

Carousel Water Sampler:

    SBE 32, S/N 0391 (36-position)
    SBE 32, S/N 0389 (12-position)

Water sample bottle:

    12-litre Niskin-X model 1010X (no TEFLON coating)
    12-position CWS system (Set 2)

Deck unit:

    SBE 11plus, S/N 0272

Under water unit:

    SBE 9plus, S/N 94766 (Pressure sensor: S/N 0786)

Temperature sensor:

    SBE 3plus, S/N 1359 (primary)
    SBE 3plus, S/N 1525 (secondary)

Conductivity sensor:

    SBE 4, S/N 1203 (primary)
    SBE 4, S/N 2435 (secondary)

Oxygen sensor:

    SBE 43, S/N 0205
      JFE Advantech RINKO-III, S/N 0037 (foil batch no. 144005A)

Pump:

    SBE 5T, S/N 3118 (primary)
    SBE 5T, S/N 3293 (secondary)

Altimeter:

    PSA-916T, S/N 1100

Deep Ocean Standards Thermometer:

    SBE 35, S/N 0022

Carousel Water Sampler:

    SBE 32, S/N 0389

Water sample bottle:

    12-litre Niskin-X model 1010X (no TEFLON coating)


(4)  Pre-cruise calibration

i.  Pressure

The Paroscientific series 4000 Digiquartz high pressure transducer (Model 
415K: 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 1027, 4 February 2011
    S/N 0786, 17 November 2009

The time drift of the pressure sensor is adjusted by periodic recertification 
corrections against a deadweight piston gauge (Model 480DA, S/N 23906; Piston 
unit, S/N 079K; Weight set, S/N 3070; 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.

S/N 1027, 19 May 2011

    slope = 1.00017335
    offset = 0.16281

S/N 0786, 27 May 2011

    slope = 0.99988759
    offset = 0.05087


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 4815, 25 January 2011
    S/N 5329, 11 February 2011
    S/N 4811, 9 February 2011
    S/N 1359, 18 May 2011
    S/N 1525, 10 June 2011

Pressure sensitivities of SBE 3s were corrected according to a method by 
Uchida et al. (2007), for the following sensors.

    S/N 4815, –3.45974716e–7 [°C/dbar]
    S/N 4811, –2.7192e–7 [°C/dbar]
    S/N 1359, –1.8386e–7 [°C/dbar]

Pressure sensitivities were not yet determined for S/N 5329 and 1525.

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. The conductivity cells have been 
replaced to newer style cells for deep ocean measurements.

Pre-cruise sensor calibrations were performed at SBE, Inc.

    S/N 2854, 1 June 2011
    S/N 3036, 1 June 2011
    S/N 1203, 25 May 2011
    S/N 2435, 2 March 2011

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 calibration was performed at SBE, Inc.

    S/N 0394, 25 October 2011
    S/N 0205, 27 May 2011

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 September 2002
    S/N 0022, 4 March 2009

Then the SBE 35 is certified by measurements in thermodynamic fixed-point 
cells of the TPW (0.01 °C) and GaMP (29.7646 °C). The slow time drift of the 
SBE 35 is adjusted by periodic recertification corrections. Precruise sensor 
calibration was performed at SBE, Inc.

    S/N 0045, 10 February 2011 (slope and offset correction)
    S/N 0022, 23 January 2011 (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.

From the end of 2011, the SBE has been applying a NIST correction to the 
fixed-point cells used for the calibration. The offset values were estimated 
for the above fixed-point cells as 140 μK (TPW) and 89 μK (GaMP) for the S/N 
0045 and 120 μK (TPW) and 89 μK (GaMP) for the S/N 0022, and the following 
NIST corrected coefficients were used in this cruise.

    S/N 0045: Slope = 1.000030, Offset = –0.001513
    S/N 0022: Slope = 1.000010, Offset = –0.000116

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 (RINKO)

RINKO (JFE Alec Co., Ltd.) is based on the ability of selected substances to 
act as dynamic fluorescence quenchers. RINKO model III is designed to use 
with a CTD system which accept an auxiliary analog sensor, and is designed to 
operate down to 7000 m.

Outputs from RINKO are the raw phase shift data. The RINKO can be calibrated 
by the Stern-Volmer equation, according to a method by Uchida et al. (2010):

    O2 (μmol/l) = [(V0 / V) – 1] / Ksv

where V is voltage, V0 is voltage in the absence of oxygen and Ksv is Stern-
Volmer constant. The V0 and the Ksv are assumed to be functions of 
temperature as follows.

    Ksv = C0 + C1 x T + C2 x T2
    V0 = 1 + C3 x T
    V = C4 + C5 x Vb

where T is CTD temperature (°C) and Vb is raw output (volts). V0 and V are 
normalized by the output in the absence of oxygen at 0°C. The oxygen 
concentration is calculated using accurate temperature data from the CTD 
temperature sensor instead of temperature data from the RINKO. The pressure-
compensated oxygen concentration O2c can be calculated as follows.

    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 salinitycompensated oxygen 
can be calculated by multiplying the factor of the effect of salt on the 
oxygen solubility (García and Gordon, 1992). García and Gordon (1992) have 
recommended the use of the solubility coefficients derived from the data of 
Benson and Krause.

Pre-cruise sensor calibrations were performed at RIGC/JAMSTEC.

    S/N 0024, 20 June 2011 S/N 0079, 6 December 2011

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.  Transmissometer

The C-Star Transmissometer (WET Labs, Inc., Philomath, Oregon, USA) measures 
light transmittance at a single wavelength over a know path. In general, 
losses of light propagating through water can be attributed to two primary 
causes: scattering and absorption. By projecting a collimated beam of light 
through the water and placing a focused receiver at a known distance away, 
one can quantify these losses. The ratio of light gathered by the receiver to 
the amount originating at the source is known as the beam transmittance. 
Suspended particles, phytoplankton, bacteria and dissolved organic matter 
contribute to the losses sensed by the instrument. Thus, the instrument 
provides information both for an indication of the total concentrations of 
matter in the water as well as for a value of the water clarity.

Transmittance (Tr) is related to the beam attenuation coefficient c by the 
relationship:

    Tr = e–cx
    x = 0.25 m (S/N CST-136DR)

where x is the pathlength through the water volume.

x.  PAR

Satlantic’s Photosynthetically Active Radiation (PAR) sensors provide highly 
accurate measurements of PAR (400 – 700 nm) for a wide range of aquatic and 
terrestrial applications. The ideal spectral response for a PAR sensor is one 
that gives equal emphasis to all photons between 400 – 700 nm. Satlantic PAR 
sensors use a high quality filtered silicon photodiode to provide a near 
equal spectral response across the entire wavelength range of the 
measurement.

    Pre-cruise sensor calibration was performed at Satlantic, LP.

        22 January 2009

 
(5) Data collection and processing

i.  Data collection

CTD system was powered on at least 20 minutes in advance of the data 
acquisition to stabilize the pressure sensor and was powered off at least two 
minutes after the operation in order to acquire pressure data on the ship’s 
deck.

The pressure windows of the transmissometer were wiped with Kimwipes wetted 
with ethanol before each CTD cast to clean the windows.

The package was lowered into the water from the starboard side and held 10 m 
beneath the surface 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 (or 20 seconds from station P10_78_1 to save time) 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 (or 12-bottles) SBE 32 
Carousel Water Sampler with 12-litre Niskin-X bottles. Before a cast taken 
water for CFCs, the bottle frame and Niskin-X bottles were wiped with 
acetone.

    Data acquisition software
        SEASAVE-Win32, version 7.18c

ii.  Data collection problems

(a) Miss trip and miss fire

Niskin bottles did not trip correctly at the following stations.

    Miss trip       Miss fire
    P10_46_1, #11   P10N_106_2, #31

(b) Detaching the fluorometer, transmissometer and LADCP

At station P10_74_2 and P10N_77_2, the fluorometer, transmissometer and LADCP 
were detached from the CTD system, because the maximum depth of the CTD cast 
exceeded the pressure capacity of the sensors.

(c) Cancellation of CTD casts

At station P10_67_1, the CTD cast was cancelled at 236 dbar of down cast, 
because the ship maneuvering equipment was on the blink. At station 
P10N_84_1, the CTD cast was cancelled at 5073 dbar of down cast because of 
rough weather.

(d) Bottle firing without stops

At following stations, the Niskin bottles were fired without stop of the CTD 
package because of rough weather.

    P10N_83_1: bottles #24~36
    P10N_87_1: bottles #14~27, #29~36


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

        SBEDataProcessing-Win32, version 7.21d

    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. When the bottle was fired without bottle firing stop, 
the duration was set to 1.0 second and the offset was set to 0.0 second, and 
a quality flag of 4 (bad) was set to the SBE 35 data. The hysteresis 
correction for the SBE 43 data (voltage) was applied for both profile and 
bottle information data.

    TCORP (original module, version 1.1) corrected the pressure sensitivity 
of the SBE 3 for both profile and bottle information data.

    RINKOCOR (original module, version 1.0) corrected the time-dependent, 
pressure-induced effect (hysteresis) of the RINKO for both profile data.

    RINKOCORROS (original module, version 1.0) corrected the time-dependent, 
pressure-induced effect (hysteresis) of the RINKO for bottle information data 
by using the hysteresis-corrected profile data.

    BOTTLESUM created a summary of the bottle data. The data were averaged 
over 4.4 seconds (or 1 second for the bottle fired without stop).

    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 
the SBE 43 oxygen sensor output (voltage) relative to the temperature data. 
Delay of the RINKO data was also compensated by 1 second advancing sensor 
output (voltage) relative to the temperature data. Delay of the 
transmissometer data was also compensated by 2 seconds advancing sensor 
output (voltage) relative to the temperature data.

    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 pressure, temperature, conductivity and SBE 43 output.

    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 and 
transmissometer data. A median value was determined by 49 scans of the 
window.

    SECTIONU (original module, version 1.1) 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 depth of the package was 1 dbar below the surface. The minimum and 
maximum numbers were automatically calculated in the module.

    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, SBE 43, and 
RINKO output.

    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 (σθ).

    SPLIT was used to split data into the down cast and the up cast.

Remaining spikes in the CTD data were manually eliminated from the 1-dbar-
averaged data. The data gaps resulting from the elimination were linearly 
interpolated with a quality flag of 6.


(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 to 
check the pressure sensor time drift. The atmospheric pressure was measured 
at the captain deck (20 m high from the base line) and subsampled one-minute 
interval as a meteorological data. Time series of the CTD deck pressure is 
shown in Fig. 3.1.1. The CTD pressure sensor offset was estimated from the 
deck pressure. Mean of the pre- and the postcasts data over the whole period 
gave an estimation of the pressure sensor offset (0.25 dbar for S/N 1027 and 
–0.47 dbar for S/N 0786) from the pre-cruise calibration. The post-cruise 
correction of the pressure data is not deemed necessary for the pressure 
sensor.

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, according to a method by Uchida et al. (2007).

Post-cruise sensor calibration for the SBE 35 was performed at SBE, Inc in 
August 2013. S/N 0045, 15 April 2012 (2nd step: fixed point calibration)

    Slope = 1.000029
    Offset = –0.001423

S/N 0022, 12 March 2012 (2nd step: fixed point calibration)

    Slope = 1.000012
    Offset = –0.000023

Offset of the SBE 35 data from the pre-calibration was estimated to be 
smaller than 0.1 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 the CTD temperature and c0, c1, and c2 
are calibration coefficients. The coefficients were determined using the data 
for the depths deeper than 950 dbar.

The primary temperature data were used for the post-cruise calibration. The 
calibration coefficients are listed in Table 3.1.1. The results of the post-
cruise calibration for the CTD temperature are summarized in Table 3.1.2 and 
shown in Fig. 3.1.2.

Fig. 3.1.1: Time series of the CTD deck pressure. Atmospheric pressure 
            deviation (magenta dots) from a standard atmospheric pressure was 
            subtracted from the CTD deck pressure. Blue and green dots 
            indicate pre- and post-cast deck pressures, respectively. Red 
            dots indicate averages of the pre- and the post-cast deck 
            pressures.


Table 3.1.1: Calibration coefficients for the CTD temperature sensors.

        Leg  Serial number  c0 (°C/dbar)  c1 (°C/day)  c2 (°C)
        ---  -------------  ------------  -----------  -------
         2       4815       –2.68889e–8   2.87072e–5   –0.0071
         3       4815       –4.08124e–8   9.57543e–6   –0.0025
         3       1359        1.13346e–7                 0.0004


Table 3.1.2: 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 950 dbar. Number of data 
            used is also shown.

      Leg  Serial number  Pressure ≥ 950 dbar  Pressure < 950 dbar
                          -------------------  -------------------
                          Number  Mean  Sdev   Number  Mean  Sdev
                                  (mK)  (mK)           (mK)  (mK)
      ---  -------------  ------  ----  ----   ------  ----  ----
       2       4815         647   0.0   0.2     1286   –0.6  7.0
       3       4815         631  –0.0   0.2     1060    0.1  7.6
       3       1359          36  –0.0   0.1       


Fig. 3.1.2: Difference between the CTD temperature (primary) and the SBE 35. 
            Blue and red dots indicate before and after the post-cruise 
            calibration using the SBE 35 data, respectively. Lower two panels 
            show histogram of the difference after the calibration.


iii.  Salinity

The discrepancy between the CTD conductivity and the conductivity calculated 
from the bottle salinity data with the CTD temperature and pressure data is 
considered to be a function of conductivity, pressure and time. The CTD 
conductivity was calibrated as

    Calibrated conductivity = c0 x C + c1 x P + c2 x C x P + c3 x t + c4

where C is CTD conductivity in S/m, P is pressure in dbar, t is time in days 
from 23 December 2011 and c0, c1, c2, c3 and c4 are calibration coefficients. 
The best fit sets of coefficients were determined by a least square technique 
to minimize the deviation from the conductivity calculated from the bottle 
salinity data.

The primary conductivity data created by the software module ROSSUM were 
basically used after the postcruise calibration for the temperature data. The 
secondary conductivity sensor was also calibrated and used instead of the 
primary conductivity data when the data quality of the primary temperature or 
conductivity data was bad. The coefficients were determined for each leg. The 
calibration coefficients are listed in Table 3.1.3. The results of the post-
cruise calibration for the CTD salinity are summarized in Table 3.1.4 and 
shown in Fig. 3.1.3.


Table 3.1.3: Calibration coefficients for the CTD conductivity sensors. 

Leg  Serial     c0          c1            c2          c3            c4
     Number            [S/(m dbar)]    (1/dbar)   [S/(m day)]     (S/m)
---  ------  --------  ------------  -----------  -----------  -----------
 2    2854   0.999999   1.52141e–7   –5.00025e–8   3.69363e–6   2.68130e–4
 3    2854   0.999969  –1.92594e–7    5.97695e–8  –1.20584e–6   4.13868e–4
 3     120   1.00070   –1.03014e–6    2.97097e–7               –1.93434e–3


Table 3.1.4: Difference between the CTD salinity and the bottle salinity 
            after the post-cruise calibration. Mean and standard deviation 
            (Sdev) (in 10–3) are calculated for the data below and above 950 
            dbar. Number of data used is also shown.

         Leg  Serial  Pressure ≥ 950 dbar   Pressure < 950 dbar
              number  -------------------   -------------------
                      Number  Mean  Sdev    Number  Mean  Sdev
         ---  ------  ------  ----  ----    ------  ----  ----
          2    2854    939    –0.0   0.6      748    0.0   4.7
          3    2854    845     0.0   0.4      549   –0.0   2.8
          3    1203     39     0.0   0.3         


Fig. 3.1.3: Difference between the CTD salinity (primary) and the bottle 
            salinity. Blue and red dots indicate before and after the post-
            cruise calibration, respectively. Lower two panels show histogram 
            of the difference after the calibration.

iv. Oxygen

The RINKO oxygen optodes (S/N 0024 and S/N 0037) were calibrated and used as 
the CTD oxygen data, since the RINKO has a fast time response. The pressure-
hysteresis corrected RINKO data was calibrated by the Stern-Volmer equation, 
basically according to a method by Uchida et al. (2010):

    [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 Vb + C6 x t + C7 x t x Vb

where Vb is the RINKO output (voltage), V0 is voltage in the absence of 
oxygen, T is temperature in °C, and t is working time (in days) of the RINKO 
sensor integrated from the first CTD cast for each leg. Time drift of the 
RINKO output was corrected. The pressure-compensated oxygen concentration O2c 
was calculated as follows.

    O2c = O2 (1 + Cpp / 1000)1/3

where p is CTD pressure (dbar) and Cp is the compensation coefficient. The 
calibration coefficients were determined by minimizing the sum of absolute 
deviation with a weight from the bottle oxygen data. The revised quasi-Newton 
method (DMINF1) was used to determine the sets.

The post-cruise calibrated temperature and salinity data were used for the 
calibration. The calibration coefficients are listed in Table 3.1.5. The 
results of the post-cruise calibration for the RINKO oxygen are summarized in 
Table 3.1.6 and shown in Fig. 3.1.4.


Table 3.1.5: Calibration coefficients for the RINKO oxygen sensors.

Leg  Serial number      c0          c1           c2           c3          c4
---  -------------  ----------  ----------  -----------  -----------  ---------
 2       0024       3.89290e–3  1.52171e–4   1.93156e–6  –5.08841e–4  –0.117182
 3       0024       4.11419e–3  1.64439e–4   2.93308e–6   4.45790e–4  –0.140317
 3       0037       3.04531e–3  1.09824e–3  –3.46770e–4   7.63642e–3  –0.146284

Table 3.1.5: Continue.

          Leg  Serial number      c5         c6          c7       Cp
          ---  -------------  --------  -----------  ----------  ----
           2       0024       0.336087   5.16436e–5  2.38398e–4  0.05
           3       0024       0.342439  –2.97398e–4  1.80689e–4  0.05
           3       0037       0.325744   0.05   


Table 3.1.6: Difference between the RINKO oxygen and the bottle ooxygen 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.

          Leg  Serial number  Pressure ≥ 950 dbar   Pressure < 950 dbar
                              Number  Mean  Sdev    Number  Mean  Sdev
                                      [μmol/kg]             [μmol/kg]
          ---  -------------  ------  ----  ----    ------  ----  ----
           2       0024        890    0.00  0.23     753    0.03  0.47
           3       0024        851    0.01  0.28     550   –0.09  0.81
           3       0037         39   –0.03  0.27       


Fig. 3.1.4: Difference between the calibrated CTD oxygen and the bottle 
            oxygen. Lower two panels show histogram of the difference.


v.  Fluorometer

The CTD fluorometer (Fl in μg/L) was calibrated with the bottle sampled 
chlorophyll-a (Chla) as

    Fl = c0 + c1 x Chla

where c0 and c1 are calibration coefficients. The CTD fluorometer data is 
slightly noisy so that the up cast profile data which was averaged over one 
decibar agree with the bottle sampled data better than the discrete CTD 
fluorometer data obtained at bottle-firing stop. Therefore, the CTD 
fluorometer data at water sampling depths extracted from the up cast profile 
data were compared with the bottle sampled chlorophyll-a data (Fig. 3.1.5) 
and the calibration coefficients are listed in Table 3.1.7.

Fig. 3.1.5: Comparison of the CTD fluorometer and the bottle sampled 
            chlorophyll-a. The solid line is the regression line.


Table 3.1.7. Calibration coefficients for the CTD fluorometer.

                    c0     c1    Standard deviation from the
                                      regression line
                 ------  ------  ---------------------------
                 –0.039  0.9218          0.05 μg/L


vi.  Transmissometer

The transmissometer is calibrated as

    Tr = (V–Vd) / (Vr–Vd)

where V is the measured signal (voltage), Vd is the dark offset for the 
instrument, and Vr is the signal for clear water. Vd can be obtained by 
blocking the light path. Vd was measured on deck before each cast and 
estimated to be 0.0012 during the cruise. Vr is estimated from the measured 
signal in the deep ocean, although the transmittance tended to decrease when 
the water depth was shallow (Fig. 3.1.6). Since the transmissometer drifted 
in time, Vr is expressed as

    Vr = 4.84280 – 6.73551e–3xt + 1.78673e–4xt2

where t is working time (in days) of the transmissometer.


vii.  PAR

The PAR sensor was calibrated with an offset correction. The offset was 
estimated from the data measured in the deep ocean during the cruise. The 
corrected data (PARc) is calculated from the raw data (PAR) as follows:

    PARc [μE m–2 s–1] = PAR – 0.046.


Fig. 3.1.6: Time series of an output signal (voltage) from transmissometer at 
            on deck before CTD casts (Vair) and deep ocean (Vdeep). The solid 
            line indicates the modeled signal in the deep clear ocean.


(7) Combining of CTD profiles

Two sets of SBE 911plus CTD system with 36 and 12-position SBE 32 were used 
at three CTD stations (Table 3.1.8). The 12-position CWS CTD system (set 2) 
can be accurately calibrated with water sampled data for the depths deeper 
than about 3000 dbar. Therefore, the CTD profiles obtained at these casts 
were combined to obtain a calibrated CTD profile from surface to bottom. The 
data between the shallow and deep profiles were linearly interpolated for 100 
dbar from the maximum depth of the shallow profile to the top of the deep 
profile used to combine (Fig. 3.1.7).


Table 3.1.8: List of deep double casts of CTD in leg 3. Set 1 is 36-position 
             CWS system and set 2 is 12-position CWS system.

   Station no.  Cast no.  Set of CTD system  Water sampling depth
   -----------  --------  -----------------  --------------------
     P10N 90       2             2           3170 dbar – bottom
                   3             1           Surface   – 2930 dbar
     P10N 92       1             2           3250 dbar – bottom
                   3             1           Surface   – 2999 dbar
     P10N 94       1             2           3332 dbar – bottom
                   3             1           Surface   – 3082 dbar


Fig. 3.1.7: Combined CTD profiles of stations P10N 90_3, 92_3, and 94_3.



References

Edwards, B., D. Murphy, C. Janzen and N. Larson (2010): Calibration, 
    response, and hysteresis in deep-sea dissolved oxygen measurements, J. 
    Atmos. Oceanic Technol., 27, 920–931.

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.

García, H. E. and L. I. Gordon (1992): Oxygen solubility in seawater: Better 
    fitting equations. Limnol. Oceanogr., 37 (6), 1307–1312.

Uchida, H., G. C. Johnson, and K. E. McTaggart (2010): CTD oxygen sensor 
    calibration procedures, The GOSHIP Repeat Hydrography Manual: A 
    collection of expert reports and guidelines, IOCCP Rep., No. 14, ICPO 
    Pub. Ser. No. 134.

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.



3.2  Bottle Salinity
     May 10, 2012

(1) Personnel
  
    Hiroshi Uchida    (JAMSTEC)
    Fujio Kobayashi   (MWJ) (Leg 2)
    Tatsuya Tanaka    (MWJ) (Leg 3)
    Hiroki Ushiromura (MWJ) (Leg 2)
    Tamami Ueno       (MWJ) (Leg 3)


(2) Objectives

Bottle salinities were measured to calibrate CTD salinity data.


(3) Instrument and Method

Salinity measurement was conducted basically based on a method by Kawano (2010).

i.  Salinity Sample Collection

Samples for salinity measurement were collected and stored in 250-mL brown 
borosilicate glass bottles with GL32 screw caps with PTFE liners (without 
cones). Each bottle and cap was rinsed three times with sample water, and the 
water was allowed to overflow the bottle. Excess water was poured out until 
the water was level with the shoulder of the bottle. The bottles were stored 
at least 12 hours in a laboratory where the salinity was to be measured for 
temperature equilibration with upside down in a carrying case.

ii. Instruments and Method

Salinity of water samples was measured with two salinometers (Autosal model 
8400B; Guildline Instruments Ltd., Ontario, Canada; serial no. 62556 for leg 
2 and serial no. 62827 for leg 3), which was modified by adding an 
peristaltic-type intake pump (Ocean Scientific International Ltd., Hampshire, 
UK) and two platinum thermometers (Guildline Instruments Ltd., model 9450). 
One thermometer monitored an ambient temperature and the other monitored a 
salinometer’s bath temperature. The resolution of the thermometers was 0.001 
°C. The measurement system was almost same as Aoyama et al. (2002). The 
salinometer was operated in the air-conditioned laboratory of the ship at a 
bath temperature of 24 °C. The ambient temperature varied from approximately 
20 to 24 °C, while the bath temperature was stable and varied within ±0.002 
°C.

A measure of a double conductivity ratio of a sample was taken as a median of 
31 readings. Data collection was started after 10 seconds and it took about 
10 seconds to collect 31 readings by a personal computer. Data were sampled 
for the sixth and seventh filling of the cell. In case where the difference 
between the double conductivity ratio of this two fillings was smaller than 
0.00002, the average value of the two double conductivity ratios was used to 
calculate the bottle salinity with the algorithm for practical salinity 
scale, 1978 (UNESCO, 1981). When the difference was grater than or equal to 
the 0.00003, we measured another additional filling of the cell. In case 
where the double conductivity ratio of the additional filling did not satisfy 
the criteria above, we measured other additional fillings of the cell within 
10 fillings in total. In case where the number of fillings was 10 and those 
fillings did not satisfy the criteria above, the median of the double 
conductivity ratios of five fillings were used to calculate the bottle 
salinity.

The measurement was conducted about from 6 to 23 hours per day and the cell 
was cleaned with soap after the measurement for each day. A total of about 
4,000 sea water samples were measured during the cruise.


(4) Results

i.  Standard Seawater

Standardization control was set to 796 (leg 2) and 482 (leg 3). The value of 
STANDBY was 5602 ± 0002 (leg 2) and 5408 ± 0.002 (leg 3), and that of ZERO 
was 0.00000 ± 0.00001 for both legs. We used IAPSO Standard Seawater (Ocean 
Scientific International Ltd., Havant, UK) batch P153 whose conductivity 
ratio was 0.99979 (double conductivity ratio is 1.99958) as the standard for 
salinity measurement. We measured 90 (leg 2) and 85 (leg 3) bottles of the 
Standard Seawater during routine measurement. Figs. 3.2.1 and 3.2.2 show the 
history of the measured double conductivity ratio of the Standard Seawater 
during legs 2 and 3.

For leg 2, the salinometer was not stable. Therefore, an offset of the 
measurements was estimated by averaging the measured double conductivity 
ratio of the Standard Seawater for each day. The estimated offset was 
subtracted from the measured double conductivity ratio of the sample. After 
the offset correction, the average of the double conductivity ratio of the 
Standard Seawater became 1.99958 and the standard deviation was 0.00002, 
which is equivalent to 0.0003 in salinity.

For leg 3, the salinometer was slightly drifted in time. Therefore, a linear 
trend of the measurements was estimated by fitting the measured double 
conductivity ratio of the Standard Seawater for whole period. The estimated 
linear trend was subtracted from the measured double conductivity ratio of 
the sample. After the correction, the average of the double conductivity 
ratio of the Standard Seawater became 1.99958 and the standard deviation was 
0.00001, which is equivalent to 0.0002 in salinity.

ii.  Sub-Standard Seawater

We also used sub-standard seawater which was deep-sea water filtered by pore 
size of 0.45 μm and stored in a 20 liter cubitainer made of polyethylene and 
stirred for at least 24 hours before measurement. It was measured every 6 
water samples in order to check the possible sudden drift of the salinometer. 
In this cruise, no remarkable sudden drift was detected for the salinometers.

iii.  Replicate Samples

We took 323 (leg 2) and 245 (leg 3) pairs of replicate samples during the 
cruise. Histograms of the absolute difference between replicate samples are 
shown in Figs. 3.2.3 and 3.2.4. The root-mean squares of the absolute 
difference of replicate samples were 0.00035 (leg 2) and 0.00017 (leg 3).

Figure 3.2.1: History of measured double conductivity ratio of the Standard 
              Seawater (P153) during leg 2. Horizontal and vertical axes 
              represents date and double conductivity ratio, respectively. 
              Red dots are raw data and blue dots are corrected data.

Figure 3.2.2: Same as Fig. 3.2.1, but for leg 3.

Figure 3.2.3: Histogram of the absolute difference between replicate samples 
              for leg 2. Horizontal axis is absolute difference in salinity 
              and vertical axis is frequency.

Figure 3.2.4: Same as Fig. 3.2.3, but for leg 3.



References 

Aoyama, M., T. Joyce, T. Kawano and Y. Takatsuki (2002): Standard seawater 
    comparison up to P129. Deep-Sea Research, I, 49, 1103–1114.

Kawano, T. (2010): Method for salinity (conductivity ratio) measurement. The 
    GO-SHIP Repeat Hydrography Manual: A Collection of Expert Reports and 
    Guidelines, IOCCP Rep. 14, ICPO Publication series 134, Version 1.

UNESCO (1981): Tenth report of the Joint Panel on Oceanographic Tables and 
    Standards. UNESCO Tech. Papers in Mar. Sci., 36, 25 pp.



3.3  Density
     February 13, 2014

(1) Personnel

    Hiroshi Uchida (JAMSTEC)
(2) Objectives

The objective of this study is to collect absolute salinity (also called 
“density salinity”) data, and to evaluate an algorithm to estimate absolute 
salinity provided along with TEOS-10 (the International Thermodynamic 
Equation of Seawater 2010) (IOC et al., 2010).

(3) Materials and methods

Seawater densities were measured during the cruise and a part of the seawater 
samples were measured in a laboratory in the Japan Agency for Marine-Earth 
Science and Technology, Yokosuka, Japan, after the cruise with an 
oscillation-type density meter (DMA 5000M, serial no. 80570578, Anton-Paar 
GmbH, Graz, Austria) with a sample changer (Xsample 122, serial no. 80548492, 
Anton-Paar GmbH). The sample changer was used to load samples automatically 
from up to ninety-six 12-mL glass vials. AC power was supplied to the density 
meter through a frequency conversion AC power supply unit (AA500F, Takasago, 
Ltd., Japan).

The water samples were collected in 100-mL PFA bottles (Sanplatec Co., 
Japan), 100-mL or 50-mL I-BOY polypropylene bottles (AS ONE, Co., Japan), and 
vacuum sealed with an aluminum bag (HRS, MAL or ALH, Meiwa Sanshou Co., Ltd, 
Japan). Densities of the samples were measured at 20 ºC by the density meter 
from two to six times for each bottle. The glass vial was sealed with 
Parafilm M (Pechiney Plastic Packaging, Inc., Menasha, Wisconsin, USA) until 
the density was measured.

Time drift of the density meter was monitored by periodically measuring the 
density of ultra-pure water (Milli-Q water, Millipore, Billerica, 
Massachusetts, USA) prepared from Yokosuka (Japan) tap water in July 2010. 
The true density (ρPW) at 20 ºC of the Milli-Q water was estimated to be 
998.2041 kg/m3 from the isotopic composition (δD = –9.08 ‰, δ18O = –58.8 ‰) 
and International Association for the Properties of Water and Steam (IAPWS)-
95 standard. An offset correction was applied to the measured density by 
using the Milli-Q water measurements (ρMilli-Q) with a slight modification of 
the density dependency (Uchida et al., 2011). The offset (ρoffset) of the 
measured density (ρ) was estimated from the following equation:

    ρoffset = (ρMilli-Q – ρPW) – (ρ – ρPW) x 0.000241 [kg/m3].

The offset correction was verified by measuring Reference Material for 
Nutrients in Seawater (RMNS) lot BF (Kanso Technos Co., Ltd., Osaka, Japan) 
along with the Milli-Q water. Reference Material for Density in Seawater 
(prototype Dn-RM1) developed with Marine Works Japan, Ltd., Kanagawa, Japan, 
and produced by Kanso Technos Co., Ltd., Osaka, Japan, was also measured at 
post-cruise measurements. The Dn-RM1 was similarly produced with the RMNS. 
Material of the bottle is not polypropylene but PFA, and vacuumed sealed 
aluminum bag (MAL) is not single but double.

Density salinity can be back calculated from measured density and temperature 
(20 ºC) with TEOS-10.

The water samples collected at stations 56, 53, 49, 45, 41, 37, 34, 31, 27, 
1, 5, and 10 were vacuum sealed with the HRS aluminum bag and measured within 
a few days after the collection. The rest of water samples were vacuum sealed 
with the HRS or ALH aluminum bag and stored in a refrigerator to measure in 
the laboratory after the cruise since the density meter was broken during the 
cruise.

(4) Results

List of the series of density measurement was shown in Table 3.3.1. The water 
samples for station 68 (#2, 5, 8, 15, 16, 22, 24, 25, and 30), 71 (#6, 10, 
16, and 29), 90 (#2, 5-12, 23, 24, 27, 29, 31, 32, and 36), 92 (#8-12), and 
110 (#10, 12, 13, 16, 17_2, 19, 23, and 28-32) were not measured because the 
aluminum bags were torn during their storage.

For the series of measurement at April 5, 2012, the density meter was largely 
drifted in time between the first and the last measurement of Milli-Q water 
(about 16 hours). In addition, magnitude of the drift was different for the 
Milli-Q water (+0.008 kg/m3) and the RMNS (+0.018 kg/m3). Therefore, linear 
time drift and offset for the sea water measurement was estimated from the 
result of the RMNS measurement. Density of the RMNS was adjusted to 1024.4826 
kg/m3 to match with the overall mean density of the RMNS (Table 3.3.1).

The measured density of the RMNS was smaller than twice the standard 
deviation from the mean for the series of measurement at January 5 and April 
6, 2012. Therefore, offset for the sea water measurement was estimated from 
the RMNS measurement. Mean density of the RMNS at the series of measurement 
was adjusted to 1024.4826 kg/m3 to match with the overall mean density of the 
RMNS (Table 3.3.1). The estimated offsets were +0.0041 and +0.0043 kg/m3 for 
the series of measurements at January 5 and April 6, respectively.

To check those time drift and offset corrections by using the RMNS 
measurements, measured densities of the Dn-RM1 were compared (Table 3.3.2). 
The measured densities agreed well with each other.

A total of 26 pairs of replicate samples were measured. The root-mean square 
of the absolute difference of replicate samples was 0.0011 g/kg.

The measured density salinity anomalies (δSA) are shown in Fig. 3.3.1. The 
measured δSA well agree with calculated δSA from Pawlowicz et al. (2011) 
which exploits the correlation between δSA and nutrient concentrations and 
carbonate system parameters based on mathematical investigation using a model 
relating composition, conductivity and density of arbitrary seawaters.


Table 3.3.1:  List of the series of density measurement.

Date          Stations (samples no.)  Mean density of RMNS  Note
                                      Lot BF (kg/m3)

2011/12/25      56                          1024.4847    relatively large variation
                                                         #15: bad (flag 4)
2011/12/26      53                          1024.4849
2011/12/27      49                          1024.4821
2011/12/29      45                          1024.4814    #12: questionable (flag 3)
2011/12/30      41                          1024.4841
2011/12/31 (1)  37                          1024.4838
2011/12/31 (2)  34                          1024.4840
2012/01/01      31                          1024.4816
2012/01/02      27                          1024.4820    relatively large variation
2012/01/04      1                           1024.4799
2012/01/05      5, 10                       1024.4831    frequent errors, large
                                                         variation, bias correction
                                                         using RMNS
2012/04/04      74, 77 (except for #6,9,    1024.4838
                 10,16,27,30,36) 
2012/04/05      15, 21, 71 (#1,3-5,11,      1024.4827    time drift correction using RMNS
                 13,20-25,28,31,32,35,36),
                 77 (#6,9,10,16,27,30,36)
2012/04/06      60 (#1,11,12,16-18,26),     1024.4829    bias correction using RMNS
                 110, 114 
2012/04/09      90                          1024.4810
2012/10/15      60 (except for #1,11,12,    1024.4823
                 16-18,26),64 (except for 
                 #30-33,35)
2012/10/18      102, 106                    1024.4833
2012/10/25 (1)  64 (#30-33,35), 68          1024.4836
2012/10/25 (2)  71, 79 (#1-16)              1024.4815
2012/10/26 (1)  79 (except for #1-16),83    1024.4825
                 (except for #23,25)
2012/10/26 (2)  83 (#23,25), 86, 92         1024.4817
2012/10/28      94                          1024.4837
2012/10/30      98                          1024.4831

                                   Average: 1024.4827 ± 0.0016


Table 3.3.2: Comparison of density measurement for the Reference Material for 
             Density in Seawater (prototype Dn-RM1).

       Date        Serial no.  Density [kg/m3]  Note
       ----------  ----------  ---------------  -----------------
       2012/04/04     050       1024.2616
       2012/04/05     051       1024.2612       drift correction
       2012/04/06     052       1024.2624       offset correction
       2012/04/09     053       1024.2590
                       Average: 1024.2611 ± 0.0015


Figure 3.3.1: Vertical distribution of density salinity anomaly measured by 
              the density meter. Absolute Salinity anomaly estimated from 
              nutrients and carbonate parameters (Pawlowicz et al., 2011) are 
              also shown for comparison.



Acknowledgment

The author thank Tamami Ueno (MWJ) for helping density measurement of station 
83 (#23,25) and 86.



References

IOC, SCOR and IAPSO (2010): The international thermodynamic equation of 
    seawater – 2010: Calculation and use of thermodynamic properties. 
    Intergovernmental Oceanographic Commission, Manuals and Guides No. 56, 
    United Nations Educational, Scientific and Cultural Organization 
    (English), 196 pp.

Pawlowicz, R., D. G. Wright and F. J. Millero (2011): The effects of 
    biogeochemical processes on ocean conductivity/salinity/density 
    relationships and the characterization of real seawater. Ocean Science, 
    7, 363– 387.

Uchida, H., T. Kawano, M. Aoyama and A. Murata (2011): Absolute salinity 
    measurements of standard seawaters for conductivity and nutrients. La 
    mer, 49, 237–244.



3.4  Oxygen
     September 27, 2013


(1) Personnel

    Yuichiro Kumamoto (Japan Agency for Marine-Earth Science and Technology)
    Miyo Ikeda (Marine Works Japan Co. Ltd)
    Misato Kuwahara (Marine Works Japan Co. Ltd)
    Shin’ichiro Yokogawa (Marine Works Japan Co. Ltd)
    Kanako Yoshida (Marine Works Japan Co. Ltd)
    Yuki Miyajima (Marine Works Japan Co. Ltd)

(2) Objectives

Dissolved oxygen is one of good tracers for the ocean circulation. Recent 
studies indicated that oxygen minimum layers in the tropical region have 
expanded (Stramma et al., 2008). Climate models predict a decline in oceanic 
dissolved oxygen concentration and a consequent expansion of the oxygen 
minimum layers under the global warming, which results mainly from decreased 
interior advection and ongoing oxygen consumption by remineralization. The 
mechanism of the decrease, however, is still unknown. During MR11-08 cruise, 
we measured dissolved oxygen concentration from surface to bottom layers at 
all the hydrocast stations along approximately 149ºE in the western Pacific. 
These stations reoccupied the WOCE Hydrographic Program P10 and P10N stations 
in 1993 and 2005. Our purpose is to evaluate temporal change in dissolved 
oxygen concentration in the western Pacific between the 1993/2005 and 
2011/12.

(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): Wako Pure Chemical Industries, Ltd., 
        volumetric standard, reference material for iodometry, Lot 
        No.EPR3227, Purity: 99.96 ± 0.01%
    CSK standard of potassium iodate: Lot EPJ3885, Wako Pure Chemical 
        Industries Ltd., 0.0100N


(4) Instruments

Burette for sodium thiosulfate and potassium iodate;
    APB-620 and APB-510 manufactured by Kyoto Electronic Co. Ltd. / 10 cm3 of  
    titration vessel

Detector;
    Automatic photometric titrator, DOT-01X 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 a 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-7 and DOT-8. Dissolved oxygen 
concentration (μmol kg-1) was calculated by the sample temperature during the 
sampling, a value of bottle salinity, the flask volume, and the titrated 
volume of the sodium thiosulfate solution. When the bottle salinity datum is 
flagged to be 3 (questionable), 4 (bad), or 5 (missing), CTD salinity 
(primary) datum is referred in the calculation alternatively.

(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 
130ºC. 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 the 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 3.4.1 
shows result of the standardization during this cruise. Error (coefficient of 
variation) of the standardization was 0.02 %, or 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 the flask each. 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 3 times blank determinations were averaged (Table 
3.4.1). The averaged blank values for DOT-7 and DOT-8 were –0.001 ± 0.002 
(standard deviation, n=21) and 0.001 ± 0.001 (standard deviation, n=21) cm3, 
respectively.

(9) Replicate sample measurement

From a single routine CTD cast, a pair of replicate samples was collected at 
three layers of 10, 1800, and 3750 dbar. In order to estimate uncertainty 
including instrumental error, one and the other of a replicate pair were 
measured using DOT-7 and DOT-8, respectively. The total amount of the 
replicate sample pairs in good measurement (flagged 2) was 331. The standard 
deviation of the replicate measurement was 0.13 μmol kg-1 that was calculated 
by a procedure (SOP23) in DOE (1994). A difference between measurements of a 
replicate pair is slightly large in samples from low-oxygen layers (Fig. 
3.4.1), which is probably due to sampling error on the deck. In the 
hydrographic data sheet, the first of the two results from a replicate pair 
was presented with the flag 2 (see section 12).

(10) Duplicate sample measurement

A duplicate sampling, water samplings from two Niskin bottles that collected 
seawater at a same depth (deeper than 1000 dbar), were conducted at 35 
stations during this cruise. Niskin numbers and sampling pressure of the 
duplicate pairs are shown in Table 3.4.2. One and the other of a duplicate 
pair were measured using DOT- 7 and DOT-8 respectively in the same way of the 
replicate sample measurements. The standard deviation of the duplicate 
measurements was calculated to be 0.14 μmol kg-1 that was equivalent with 
that of the replicate measurements (0.13 μmol kg-1, see section 9), 
suggesting that there was no problem in a water sampling system during our 
CTD casts.

(11) CSK standard measurements

The CSK standard is a commercial potassium iodate solution (0.0100 N) for 
analysis of dissolved oxygen. We titrated the CSK standard solutions (Lot 
EPJ3885) against our KIO3 standards prepared in our laboratory in 2010 and 
2011 (Table 3.4.3). A good agreement among them confirms that there was no 
systematic shift in our oxygen analyses using our KIO3 standards during 2010 
and 2011.

(12) 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 (Table 3.4.4). 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 at the sampling layer was plotted against 
   sampling pressure. Any points not lying on a generally smooth trend were 
   noted.

b. A difference between bottle oxygen and CTD oxygen (OPTODE sensor) was then 
   plotted against sampling pressure. 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 there was problem in the measurement, the datum was flagged 4.

e. 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 according to the steps a, b, c, and d.


Table 3.4.1: Results of the standardization and the blank determinations 
             during MR11-08.

                KIO3 No.                         DOT-7          DOT-8
            ------------------  Na2S2O3 No.  -------------  -------------    Stations
  (UTC)      #      ID No.                    E.P.  blank    E.P.  blank
----------  --  --------------  -----------  -----  ------  -----  ------  ------------
                                                                           P10-059,058, 
                                                                           057,056,055,
2011/12/22  05  20110523-05-02  20110602-01  3.953  -0.002  3.957  -0.001  054,053,052,
                                                                           051,050,049,
                                                                           048,047,046,
                                                                           045

                                                                           P10-044,043,
2011/12/28  05  20110523-05-01  20110602-01  3.952  -0.001  3.956   0.001  042,041,040, 
                                                                           039

                                                                           P10-038,037,
                                                                           036,035,034,
2011/12/29  05  20110523-05-07  20110602-02  3.956  -0.003  3.961  -0.001  033,032,031,
                                                                           030,029,028,
                                                                           027

                                                                           P10-001,002,
                                                                           003,004,005,
                                                                           006,007,008,
2012/01/03  05  20110523-05-08  20110602-02  3.963   0.000  3.964   0.003  009,010,011,
                                                                           012,013,014,
                                                                           015,016,017,
                                                                           018,019,020,
                                                                           021,022

2012/01/07  05  20110523-05-05  20110602-03  3.959  -0.001  3.961   0.001  P10-023,024,
                                                                           025,026

                                                                           P10-059,060,
                                                                           061,062,063,
2012/ 1/14  06  20110524-06-03  20110602-03  3.963  -0.001  3.964   0.001  064,065,066,
                                                                           067,068,069,
                                                                           070,071,072,
                                                                           073

                                                                           P10-074,P10N-
                                                                           075,076,077,
                                                                           078,079,080,
2012/01/19  06  20110524-06-05  20110602-04  4.075  -0.004  4.076   0.000  081,082,083,
                                                                           084,085,088,
                                                                           086,087,090,
                                                                           092,094,096


                                                                           P10N-098,100,
2012/02/01  06  20110524-06-01  20110602-05  3.957  -0.002  3.959   0.001  102,104,106,
                                                                           110,112,114,
                                                                           115


Figure 3.4.1: Oxygen difference between measurements of a replicate pair 
              against oxygen concentration.


Table 3.4.2: Results of the duplicate sample measurements during MR11-08.

    Leg  Stations  Pres.  #1 Niskin  #1 Oxygen  #2 Niskin  #2 Oxygen   Difference
                   (db)              [μmol/kg]             [μmol/kg]  [(μmol/kg)2]
    ---  --------  -----  ---------  ---------  ---------  ---------  ------------
 1   2    P10-59   5656   1  X12J01   176.21     2 X12J02   176.25       0.002
 2   2    P10-58   5500   2  X12J02   174.49     3 X12J03   174.42       0.005
 3   2    P10-57   5170   2  X12J02   173.25     4 X12J04   173.33       0.006
 4   2    P10-56   5080   2  X12J02   172.65     5 X12J05   172.50       0.023
 5   2    P10-55   4750   2  X12J02   164.09     6 X12J06   164.11       0.000
 6   2    P10-54   4420   2  X12J02   164.89     7 X12J07   164.94       0.003
 7   2    P10-53   4330   2  X12J02   163.54     8 X12J08   163.61       0.005
 8   2    P10-52   4000   2  X12J02   155.00     9 X12J09   154.90       0.010
 9   2    P10-44   3830   2  X12J02   155.70    10 X12J10   155.56       0.020
10   2    P10-43   3500   2  X12J02   149.74    11 X12J11   149.56       0.032
11   2    P10-42   3170   5  X12102   143.09    12 X12J12   143.07       0.000
12   2    P10-41   3080   2  X12103   139.96    13 X12101   140.13       0.029
13   2    P10-38   2870   4  X12104   138.17    14 X12J14   138.00       0.029
14   2    P10-37   2600   2  X12103   129.87    15 X12J15   129.92       0.002
15   2    P10-36   2330   2  X12103   119.45    16 X12J16   119.35       0.010
16   2    P10-35   2270   2  X12103   117.47    17 X12J17   116.93       0.292
17   2    P10-34   2000   2  X12103   113.64    18 X12J18   113.39       0.063
18   2    P10-33   1730   2  X12103   103.02    19 X12J19   102.90       0.014
19   2    P10-32   1670   2  X12103   101.57    20 X12001   101.45       0.014
20   2    P10-31   1400   2  X12103    96.37    21 X12J21    96.64       0.073
21   2    P10-30   1130   2  X12103    92.36    22 X12J22    92.70       0.116
22   2    P10-4    1400   2  X12103   109.34    21 X12J36   109.40       0.004
23   2    P10-5    1670   2  X12103   110.04    20 X12J35   109.89       0.023
24   2    P10-6    1730   2  X12103   109.66    19 X12J34   109.45       0.044
25   2    P10-12   1930   2  X12103   116.36    18 X12J33   116.08       0.078
26   2    P10-13   2200   2  X12103   125.37    17 X12J32   125.40       0.001
27   2    P10-15   2330   2  X12103   128.02    16 X12046   128.23       0.044
28   2    P10-16   2600   2  X12103   135.43    15 X12J30   135.42       0.000
29   2    P10-17   2870   2  X12103   139.94    14 X12J29   139.56       0.144
30   2    P10-18   2930   2  X12103   140.07    13 X12J28   139.79       0.078
31   2    P10-19   3250   2  X12103   144.23    12 X12J27   143.98       0.063
32   2    P10-21   3920   2  X12103   152.71     9 X12J25   152.57       0.020
33   2    P10-22   4500   2  X12103   156.23     7 X12J23   156.01       0.048
34   2    P10-23   4330   2  X12103   155.42     8 X12J24   155.31       0.012
35   2    P10-24   3670   2  X12103   148.59    10 X12J26   148.72       0.017


Table 3.4.3: Results of the CSK standard (Lot EPJ3885) measurements on board.

Date (UTC)    KIO3 ID No.          DOT-7                DOT-8          Remarks
                            Conc. (N) error (N)  Conc. (N)  error (N) 
----------  --------------  --------  ---------  ---------  ---------  -------------
2011/12/22  20110523-05-02  0.010008  0.000003   0.010008   0.000007   MR11-08 Leg-2
2012/01/14  20110524-06-07  0.010009  0.000002   0.010005   0.000009   MR11-08 Leg-3

Date (UTC)    KIO3 ID No.          DOT-7                DOT-8          Remarks
                            Conc. (N) error (N)  Conc. (N)  error (N) 
----------  --------------  --------  ---------  ---------  ---------  -------------
2011/05/27  20100630-01-11  0.010008  0.000005      −          −        before cruise
2011/05/30  20110524-07-12  0.010007  0.000004      −          −        before cruise
2011/05/31  20110523-05-12  0.010006  0.000007      −          −        before cruise
2011/06/01  20110523-01-12  0.010006  0.000010                          before cruise


Table 3.4.4: Summary of assigned quality control flags.

                      Flag  Definition
                      ----  --------------------
                       2    Good                  3080
                       3    Questionable             4
                       4    Bad                      4
                       5    Not report (missing)     0
                                           Total  3088


(13) Preliminary Results

i. Comparison of oxygen measurements at a cross point

We compared a vertical profile of oxygen concentration at a cross point 
(24ºN/149ºE) from this cruise with that from our past cruise (MR05-05). The 
first and second measurements were conducted on 30-Dec.-2005 (MR05-05_P03-
X10, 24.486ºN/149.356ºE) and 17-January-2012 (MR11-08_P10-067, 
24.241ºN/149.033ºE), respectively. Below layers below about 2000 dbar, the 
vertical profiles in 2005 and 2011 agree well within the analytical error 
(Fig. 3.4.2).

ii. Distribution of dissolved oxygen along WHP-P10/P10N in 2011/12

Figure 3.4.3 shows that a tongue-shaped oxygen minima is lying around 500 – 
1500 m depth. The highest concentration was measured in surface waters of the 
northernmost stations off Hokkaido. Another high-oxygen water was found in 
bottom waters of the north of 10ºN, which corresponds to the Circumpolar Deep 
Water (CDW). The basin-scale distribution of dissolved oxygen in 2011/12 well 
agrees with those obtained in 1993 and 2005.

iii. Decadal changes in dissolved oxygen along the WHP-P10/P10N line from 
     2005 and 2011/12

Along the P10/P10N line, difference in dissolved oxygen concentration between 
2005 and 2011/12 was large (< about 10 μmol/kg) above 1000 m depth, where the 
vertical gradient of dissolved oxygen is sharp. In deeper layers dissolved 
oxygen change less than 10 μmol/kg were also observed in some regions, 
implying influence of heaving and internal waves. In addition, we found 1~2 
μmol/kg of oxygen decrease in near bottom waters between 10ºN and 30ºN.


Figure 3.4.2: Vertical profiles of bottle oxygen concentration at a cross 
              point (24ºN/149ºE) from MR05-05 (black circles) and MR11-08 
              cruises (white circles).

Figure 3.4.3: Transect of bottle oxygen concentration (μmol/kg) along the 
              cruse track of MR11-08 in the winter of 2011-2012.




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 
    (1994): Requirements for WOCE Hydrographic Programme Data Reporting, WHPO 
    Pub. 90-1 Rev. 2, May 1994 Woods Hole, Mass., USA.

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.

Stramma, L., G. C. Johnson, J. Sprintall, V. Mohrholz (2008): Expanding 
    Oxygen-Minimum Zones in the Tropical Oceans, Science, 320, 655-668.



3.5  Nutrients
     June 13, 2012 (ver. 2.0)

(1) Personnel

      Michio AOYAMA (Meteorological Research Institute / Japan Meteorological 
      Agency, Principal Investigator)

    LEG 2

      Minoru KAMATA (Department of Marine Science, Marine Works Japan Ltd.)
      Kenichiro SATO (Department of Marine Science, Marine Works Japan Ltd.)
      Masanori ENOKI (Department of Marine Science, Marine Works Japan Ltd.)

    LEG 3

      Minoru KAMATA (Department of Marine Science, Marine Works Japan Ltd.)
      Kenichiro SATO (Department of Marine Science, Marine Works Japan Ltd.)
      Yasuhiro ARII (Department of Marine Science, Marine Works Japan Ltd.)


(2) Objectives

The objectives of nutrients analyses during the R/V Mirai MR11–08 cruise, 
WOCE P10 revisited cruise in 2011/2012, in the western Pacific Ocean are as 
follows;

- Describe the present status of nutrients concentration with excellent 
  comparability.
- The determinants are nitrate, nitrite, silicate and phosphate.
- Study the temporal and spatial variation of nutrients concentration based 
  on the previous high quality experiments data of WOCE previous P10 cruises 
  in 1993 and 2005, 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, silicate and 
  phosphate 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 95 QuAAtro 2-HR runs for the samples at 101 stations in MR11–08. The 
total amount of layers of the seawater sample reached up to 3091 for MR11–08. 
We made duplicate measurement at all layers.


(4) Instrument and Method

(4.1) Analytical detail using QuAAtro 2-HR systems (BL-Tech)

Nitrate + nitrite and nitrite were analyzed according to the modification 
method of Grasshoff (1970). The sample nitrate was reduced to nitrite in a 
cadmium tube inside of which was coated with metallic copper. The sample 
streamed with its equivalent nitrite was treated with an acidic, 
sulfanilamide reagent and the nitrite forms nitrous acid which reacted with 
the sulfanilamide to produce a diazonium ion. N-1-Naphthylethylene-diamine 
added to the sample stream then coupled with the diazonium ion to produce a 
red, azo dye. With reduction of the nitrate to nitrite, both nitrate and 
nitrite reacted and were measured; without reduction, only nitrite reacted. 
Thus, for the nitrite analysis, no reduction was performed and the alkaline 
buffer was not necessary. Nitrate was computed by difference.

The silicate method was analogous to that described for phosphate. The method 
used was essentially that of Grasshoff et al. (1983), wherein silicomolybdic 
acid was first formed from the silicate in the sample and added molybdic 
acid; then the silicomolybdic acid was reduced to silicomolybdous acid, or 
“molybdenum blue” using ascorbic acid as the reductant. The analytical 
methods of the nutrients, nitrate, nitrite, silicate and phosphate, during 
this cruise were same as the methods used in (Kawano et al. 2009).

The phosphate analysis was a modification of the procedure of Murphy and 
Riley (1962). Molybdic acid was added to the seawater sample to form 
phosphomolybdic acid which was in turn reduced to phosphomolybdous acid using 
L-ascorbic acid as the reductant.

The details of modification of analytical methods used in this cruise are 
also compatible with the methods described in nutrients section in GO-SHIP 
repeat hydrography manual (Hydes et al., 2010). The flow diagrams and 
reagents for each parameter are shown in Figures 3.5.1 to 3.5.4.


(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 1 g NEDA, C10H7NHCH2CH2NH2·2HCl, in 1000 ml of DIW and add 10 ml 
  concentrated HCl. After mixing, 1 ml Triton(R)X-100 (50 %f solution in 
  ethanol) is added.
  Stored in a dark bottle.


Figure 3.5.1: NO3+NO2 (1ch.) 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. After mixing, 1 ml Triton(R)X-100 (50 %f solution in 
  ethanol) is added. This reagent was stored in a dark bottle.


Figure 3.5.2: NO2 (2ch.) Flow diagram.


(4.4) Silicate Reagents

Molybdic acid, 0.06 M (2 %w/v)
  Dissolve 15 g disodium Molybdate(VI) dihydrate, Na2MoO4·2H2O, in 980 ml 
  DIW, add 8 ml concentrated H2SO4. After mixing, 20 ml sodium dodecyl 
  sulphate (15 %solution in water) is added.
Oxalic acid, 0.6 M (5 %w/v)
  Dissolved 50 g oxalic acid anhydrous, HOOC:COOH, in 950 ml of DIW.

Ascorbic acid, 0.01M (3 %w/v)
  Dissolved 2.5g L (+)-ascorbic acid, C6H8O6, in 100 ml of DIW. This reagent 
  was freshly prepared before every measurement.


Figure 3.5.3. SiO2 (3ch.) Flow diagram.


(4.5) Phosphate Reagents

Stock molybdate solution, 0.03M (0.8 %w/v)
  Dissolved 8 g disodium molybdate (VI) dihydrate, Na2MoO4·2H2O, and 0.17 g 
  antimony potassium tartrate, C8H4K2O12Sb2·3H2O, in 950 ml of DIW and added 
  50 ml concentrated H2SO4.

Mixed Reagent
  Dissolved 1.2 g L (+)-ascorbic acid, C6H8O6, in 150 ml of stock molybdate 
  solution. After mixing, 3 ml sodium dodecyl sulphate (15 %solution in 
  water) was added in leg3 of this cruise, 4mL sodium dodecyl sulphate (15 %
  solution in water) was added in leg2 because to reduce relatively noisy 
  signals. This reagent was freshly prepared before every measurement.
Reagent for sample dilution
  Dissolved sodium chloride, NaCl, 10 g in ca. 950 ml of DIW, added 50 ml 
  acetone and 4 ml concentrated H2SO4. After mixing, 5 ml sodium dodecyl 
  sulphate (15 %solution in water) was added.


Figure 3.5.4. PO4 (4ch.) Flow diagram.


(4.6) Sampling procedures

Sampling of nutrients followed that oxygen, salinity and trace gases. 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 were put into water bath 
adjusted to ambient temperature, 24 ± 2 deg. C, in about 30 minutes before 
use to stabilize the temperature of samples in MR11–08.

No transfer was made and the vials were set an auto sampler tray directly. 
Samples were analyzed after collection basically within 24 hours in MR11–08.

(4.7) Data processing

Raw data from QuAAtro 2-HR was treated as follows:

- Checked baseline shift.
- Checked the shape of each peak and positions of peak values taken, and then 
  changed 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.
- Loaded 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 ware and polymethylpentene (PMP) ware used were 
gravimetrically calibrated. Plastic volumetric flasks were gravimetrically 
calibrated at the temperature of use within 0 to 4 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 0 to 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 0 to 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 nitrite standard, “sodium nitrate” provided by Wako, CAS No. : 7632-00-0, 
was used. The assay of nitrite salts was determined according JIS K8019 were 
98.31%. 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 HC097572 is used. The silicate concentration is certified by NIST-SRM3150 
with the uncertainty of 0.5 %. Factor of HC097572 was signed 1.000, however 
we reassigned the factor as 0.976 from the result of comparison among RMNS in 
MR11-E02 cruise.

For phosphate standard, “potassium dihydrogen phosphate anhydrous 99.995 
suprapur®” provided by Merck, CAS No. : 7778-77-0, was used.

Ultra pure water

Ultra pure water (MilliQ water) freshly drawn was used for preparation of 
reagents, standard solutions 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 Jan 2011.

Treatment of silicate standard due to high alkalinity

Since the silicon standard solution Merck CertiPUR® is in NaOH 0.5 mol/l, we 
need to dilute and neutralize to avoid make precipitation of MgOH2 etc. When 
we make B standard, silicon standard solution is diluted by factor 12 with 
pure water and neutralized by HCl 1.0 mol/l to be about 7. After that B 
standard solution is used to prepare C standards.

(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 3.5.1. The C standard is prepared according recipes as shown in Table 
3.5.2. 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.

The calibration curves for each run were obtained using 6 levels, C-1, C-2, 
C-3, C-4, C-5 and C-6.


Table 3.5.1: Nominal concentrations of nutrients for A, B and C standards.

                      A      B   C-1  C-2  C-3  C-4  C-5   C-6
          --------  -----  ----  ---  ---  ---  ---  ---  -----
          NO3(μM)   45000   900  BS   BU   BT   BD   BF    55
          NO2(μM)   4000     20  BS   BU   BT   BD   BF     1.2
          SiO2(μM)  36000  2880  BS   BU   BT   BD   BF   167
          PO4(μM)   3000     60  BS   BU   BT   BD   BF     3.6


Table 3.5.2: Working calibration standard 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 
3.5.3(a) to (c).


Table 3.5.3(a): Timing of renewal of in-house standards.

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


Table 3.5.3(b): Timing of renewal of in-house standards.

Working standards                       Renewal
--------------------------------------  ----------------------------
C-6 Std. (mixture of B-1 and B-2 Std.)  24 hours


Table 3.5.3(c): Timing of renewal of in-house standards for reduction estimation.

Reduction estimation                    Renewal
--------------------------------------  ----------------------------
D-1 Std. (3600μM NO3)                   8 days
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., 2006, 2007, 2008, 2009). In the previous worldwide 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 to 2 %, 1 to 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).

During the period from 2003 to 2010, RMNS were used to keep comparability of 
nutrients measurement among the 8 cruises of CLIVAR project (Sato et al., 
2010) , MR10–05 cruise for Arctic research (Aoyama et al., 2010) and MR10–06 
cruise for “Change in material cycles and ecosystem by the climate change and 
its feedback” (Aoyama et al., 2011).

(6.1) RMNSs for this cruise

RMNS lots BS, BU, BT, BD and BF, which cover full range of nutrients 
concentrations in the western Pacific Ocean are prepared. 80 sets of BS, BU, 
BT, BD and BF are prepared.

One hundred forty bottles of RMNS lot BE are prepared for MR11–08. Lot BE was 
used all stations. 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 13-24 deg. C.

(6.2) Assigned concentration for RMNSs

We assigned nutrients concentrations for RMNS lots BS, BU, BT, BD, BE, and BF 
as shown in Table 3.5.4.


Table 3.5.4: Assigned concentration of RMNSs (in μmol kg-1).

                       Nitrate  Phosphate  Silicate  Nitrite
                       -------  ---------  --------  -------
                BS*      0.07     0.064      1.61    0.02
                BU*      3.97     0.379     20.30    0.07
                BT*     18.21     1.320     41.00    0.47
                BD*     29.86     2.194     64.39    0.05
                BE**    36.70     2.662     99.20    0.03
                BF***   41.39     2.809     150.23†  0.02
       --------------------------------------------------------------
         * The values are assigned for this cruise on 27 July 2011.
        ** The values are assigned for this cruise on 4 April 2009
           (Table 3.4.4 in WHP P21 REVISIT DATA BOOK).
       *** The values are assigned for this cruise on 10 October 2007
           (Table 3.4.4 in WHP P1, P14 REVISIT DATA BOOK).
         † This value is changed in MR11–03 cruise.
       

(6.3) The homogeneity of RMNSs

The homogeneity of lot BE used in MR11–08 cruise and analytical precisions 
are shown in Table 3.5.5. These are for the assessment of the magnitude of 
homogeneity of the RMNS bottles those are used during the cruise. As shown in 
Table 3.5.5 homogeneity of RMNS lot BE for nitrate, phosphate and silicate 
are the same magnitude of analytical precision derived from fresh raw 
seawater in January 2009.


Table 3.5.5: Homogeneity of lot BE derived from simultaneous 209 samples 
             measurements and analytical precision onboard R/V Mirai in MR11–08.

                         Nitrate  Phosphate  Silicate
                         -------  ---------  --------
                           CV %      CV %      CV %
              BE           0.17      0.28      0.17
              Precision    0.12      0.20      0.14
              BE: N=209


Figure 3.5.6: Time series of RMNS-BE of silicate for MR11–08.

Figure 3.5.7: Time series of RMNS-BE of phosphate for MR11–08.


(6.4) Comparability of RMNSs during the periods from 2003 to 2011

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 2009. 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 3.5.6, the nutrients 
concentrations of RMNSs were in good agreement among the measurements during 
the period from 2003 to 2011. For the silicate measurements, we show lot 
numbers and chemical company names of each cruise/ measurement in the 
footnote. As shown in Table 3.5.6, there shows less comparability among the 
measurements due to less comparability among the standard solutions provided 
by chemical companies in the silicate measurements.


Table 3.5.6 (a): Comparability for nitrate (in μmol kg-1).

                                                                   RM Lots
Cruise / Lab.            -----------------------------------------------------------------------------------------------
                          AH    unc.   AZ     unc.   BA     unc.   AX     unc.   AV     unc.   BC     unc.   BE     unc.
------------------------------------------------------------------------------------------------------------------------
                                                                   Nitrate
                         -----------------------------------------------------------------------------------------------
2003
2003intercomp_repeorted  35.23  0.06                             21.39
MR03-K04 Leg1            35.25
MR03-K04 Leg2            35.37
MR03-K04 Leg4            35.37
MR03-K04 Leg5            35.34

2005
MR05-02                               42.30         0.07    0.02  21.45   0.07  33.35   0.06  40.70   0.06
MR05-05_1 precruise      35.65  0.05  42.30   0.10  0.07    0.00  21.41   0.01  33.41   0.02  40.76   0.03
MR05-05_1                             42.33         0.07    0.01  21.43   0.05  33.36   0.05  40.73   0.85
MR05-05_2 precruise                   42.33         0.08    0.00  21.39   0.02  33.36   0.05  40.72   0.03
MR05-05_2                             42.34         0.07    0.01  21.44   0.05  33.36   0.05  40.73   0.06
MR05-05_3 precruise                   42.35         0.06    0.00  21.49   0.01  33.39   0.01  40.79   0.01
MR05-05_3                             42.36         0.07    0.01  21.44   0.04  33.37   0.05  40.75   0.05

2006 
2006intercomp                         42.24   0.04  0.04    0.00  21.40   0.02  33.32   0.03  40.63   0.04
2003intercomp_revisit    35.40  0.03

2007
MR07-04_1 precruise      35.74  0.03                0.07    0.00  21.59   0.02  33.49   0.03  40.83   0.03
MR07-04_2 precruise      35.80  0.01                0.08    0.00  21.60   0.01  33.47   0.01  40.92   0.02
MR07-04                                             0.08    0.01  21.41   0.06  33.38   0.05  40.77   0.05
MR07-06_1 precruise      35.61  0.02                0.07    0.00  21.44   0.01  33.43   0.02  40.79   0.02
MR07-06_2 precruise      35.61  0.04                0.06    0.00  21.43   0.02  33.54   0.04  40.79   0.05
MR07-06_1                                           0.08    0.01  21.44   0.03  33.41   0.05  40.81   0.04
MR07-06_2                                           0.09    0.01  21.44   0.03  33.39   0.06  40.81   0.04

2008
2008intercomp_report                                0.08    0.00  21.44   0.02
2006intercomp_revisit                 42.27   0.04  0.07    0.00  21.47   0.02  33.34   0.03
2003intercomp_revisit    35.35  0.04

2009
MR09-01_0 precruise                   42.36   0.02  0.07    0.00  21.43   0.01  33.42   0.02  40.81   0.02  36.70  0.02
MR09-01_1                             42.42   0.06  0.11    0.01  21.51   0.04  33.53   0.04  40.82   0.11  36.74  0.04
MR09-01_2                             42.43   0.05                21.54   0.03  33.53   0.03                36.74  0.03
INSS stability test_1    35.76  0.22                0.08    0.01  21.49   0.02  33.45   0.03


2010
SGONS stability test_2                42.46   0.05  0.10    0.00  21.51   0.02  33.52                       36.76  0.02
SGONS stability test_3                42.48         0.09          21.52         33.63                       36.77 

2011
SGONS stability test_4                42.56   0.07  0.08    0.01  21.62   0.01  33.65   0.07                36.83  0.03
SGONS stability test_5                42.49   0.05  0.06    0.00                                            36.87  0.06
MR11-08_2                                                                                                   36.83  0.07
SGONS stability test_6
MR11-08_3                                                                                                   36.83  0.06


Table 3.5.6 (b). Comparability for Phosphate (in μmol kg-1).

                                                                   RM Lots
Cruise / Lab.            -----------------------------------------------------------------------------------------------
                          AH    unc.   AZ     unc.   BA     unc.   AX     unc.   AV     unc.   BC     unc.   BE     unc.
------------------------------------------------------------------------------------------------------------------------
                                                                   Phosphate
                         -----------------------------------------------------------------------------------------------

2003
2003intercomp            2.141  0.001
MR03-K04 Leg1            2.110
MR03-K04 Leg2            2.110
MR03-K04 Leg4            2.110
MR03-K04 Leg5            2.110

2005
MR05-02                               3.010         0.061  0.010  1.614  0.008  2.515  0.008  2.778  0.010
MR05-05_1 precruise      2.148  0.006 3.020  0.010  0.045  0.000  1.620  0.001  2.517  0.002  2.781  0.002
MR05-05_1                             3.016         0.063  0.007  1.615  0.006  2.515  0.007  2.778  0.033
MR05-05_2 precruise                   3.015         0.066  0.000  1.608  0.001  2.510  0.001  2.784  0.002
MR05-05_2                             3.018         0.064  0.005  1.614  0.004  2.515  0.005  2.782  0.006
MR05-05_3 precruise                   3.020         0.060  0.000  1.620  0.001  2.517  0.002  2.788  0.002
MR05-05_3                             3.016         0.061  0.004  1.618  0.005  2.515  0.004  2.779  0.008

2006
2006intercomp                         3.018  0.002  0.071  0.000  1.623  0.001  2.515  0.001  2.791  0.001
2003intercomp_revisit    2.141  0.001

2007
MR07-04_1 precruise      2.140  0.002               0.062  0.000  1.620  0.001  2.512  0.002  2.782  0.002
MR07-04_2 precruise      2.146  0.002               0.056  0.000  1.620  0.001  2.517  0.002  2.788  0.002
MR07-04                                             0.066  0.004  1.617  0.005  2.513  0.004  2.781  0.007
MR07-06_1 precruise      2.144  0.001               0.066  0.000  1.617  0.001  2.517  0.001  2.790  0.001
MR07-06_2 precruise      2.146  0.002               0.067  0.000  1.620  0.001  2.517  0.002  2.789  0.002
MR07-06_1                                           0.064  0.004  1.620  0.003  2.515  0.003  2.783  0.005
MR07-06_2                                           0.066  0.004  1.619  0.005  2.515  0.003  2.785  0.006

2008
2008intercomp_report                                0.068  0.000  1.615  0.005
2006intercomp_revisit                 3.014  0.008  0.065  0.000  1.627  0.005  2.513  0.007
2003intercomp_revisit    2.131  0.006

2009
MR09-01_0 precruise                   3.017  0.001  0.074  0.000  1.619  0.001  2.520  0.001  2.790  0.001  2.662  0.001
MR09-01_1                             3.019  0.005  0.072  0.002  1.623  0.004  2.528  0.003  2.783  0.004  2.668  0.005
MR09-01_2                             3.018  0.004                1.625  0.003  2.527  0.003                2.668  0.003
INSS stability test_1    2.134  0.008               0.069  0.001  1.606  0.001  2.512  0.003  

2010
SGONS stability test_2                3.012  0.008  0.059  0.001  1.618  0.004  2.520  0.008                2.663  0.006
SGONS stability test_3                3.024         0.055         1.617         2.528                       2.666
                                     
2011
SGONS stability test_4                3.017  0.006  0.066  0.004  1.624  0.005  2.533  0.030                2.668  0.006
SGONS stability test_5                3.011  0.004  0.003                                                   2.665  0.002
MR11-08_2                                                                                                   2.676  0.008 
SGONS stability test_6
MR11-08_3                                                                                                   2.676  0.007


Table 3.5.6 (C). Comparability for Silicate (in μmol kg-1).

                                                                   RM Lots
Cruise / Lab.            -----------------------------------------------------------------------------------------------
                          AH    unc.   AZ     unc.   BA     unc.   AX     unc.   AV     unc.   BC     unc.   BE     unc.
------------------------------------------------------------------------------------------------------------------------
                                                                   Silcate
                         -----------------------------------------------------------------------------------------------

2003
2003intercomp *         130.51  0.20
MR03-K04 Leg1 **        132.01
MR03-K04 Leg2 **        132.26
MR03-K04 Leg4 **        132.28
MR03-K04 Leg5 **        132.19

2005
MR05-02 #                            133.69         1.61   0.05   58.04  0.11   153.92  0.19  155.93  0.19
MR05-05_1 precruise ##  132.49  0.13 133.77  0.02   1.51   0.00   58.06  0.03   153.97  0.09   15.65  0.09
MR05-05_1 ##                         133.79         1.59   0.07   58.01  0.12   154.01  0.26  156.08  0.36
MR05-05_2 precruise ##               133.78         1.58   0.00   57.97  0.04   154.07  0.09  156.21  0.10
MR05-05_2 ##                         133.88         1.59   0.06   58.00  0.09   154.05  0.16  156.14  0.15
MR05-05_3 precruise ##               134.02         1.57   0.00   58.05  0.05   154.07  0.14  156.11  0.14
MR05-05_3 ##                         133.79         1.60   0.05   57.98  0.09   153.98  0.18  156.08  0.13

2006
2006intercomp $                      133.83  0.07   1.64   0.00   58.20  0.03   154.16  0.08  156.31  0.08
2003intercomp_revisit $ 132.55  0.07

2007
MR07-04_1 precruise $$  133.38  0.06                1.61   0.00   58.46  0.03   154.82  0.07  156.98  0.07
MR07-04_2 precruise $$  133.15  0.12                1.69   0.00   58.44  0.05   154.87  0.14  156.86  0.14
MR07-04 $$                                          1.62   0.07   58.11  0.11   154.45  0.21  156.62  0.48
MR07-06_1 precruise $$  133.02  0.09                1.64   0.00   58.50  0.04   155.06  0.11  156.33  0.11
MR07-06_2 precruise $$  132.70  0.07                1.56   0.00   58.25  0.03   154.39  0.08  156.57  0.08
MR07-06_1 $$                                        1.61   0.04   58.13  0.08   154.48  0.13  156.64  0.08
MR07-06_2 $$                                        1.58   0.07   58.04  0.10   154.38  0.16  156.61  0.13

2008
2008intercomp ¥                                     1.64   0.00   58.17  0.05
2006intercomp_re ¥                   134.11  0.11   1.65   0.00   58.26  0.05   154.36  0.12
2003intercomp_re ¥      132.11  0.11

2009
MR09-01_0 precruise ¥                133.93  0.04   1.57   0.00   58.06  0.02   154.23  0.05  156.16  0.05  99.20  0.03
MR09-01_1 ¥                          133.97  0.11   1.34   0.11   58.15  0.08   154.48  0.09  155.89  0.13  99.24  0.08
MR09-01_2 ¥                          133.96  0.11                 58.19  0.08   154.42  0.12                99.23  0.08
INSS stability          132.40  0.35                1.69   0.02   58.18  0.02   154.43  0.09    
  test_1 ¥¥

2010
SGONS stability                      133.89  0.12   1.58   0.02   58.15  0.04   154.43  0.21                99.20  0.07
  test_2 ¥¥  
SGONS stability                      134.20         1.58          58.10         154.90                      99.18 
  test_3 ¥¥  

2011
SGONS stability test_4+              134.16  0.09   1.68   0.04   58.26  0.05   154.56  0.05                99.30  0.07
SGONS stability test_5+              133.27  0.21   1.49   0.02                                             98.82  0.18
MR11-08_2++                                                                                                 99.21  0.17
SGONSstability test_6++
MR11-08_3++                                                                                                 99.25 0.18
------------------------------------------------------------------------------------------------------------------------
List of lot numbers: *: Kanto 306F9235; **: Kanto 402F9041; #: Kanto 507F9205; ##: Kanto 609F9157; $: Merck OC551722;
$$: Merck HC623465; ¥: Merck HC751838; ¥¥: HC814662; +: HC074650; ++: HC097572


(7) Quality control

(7.1) Precision of nutrients analyses during the cruise

Precision of nutrients analyses during the cruise was evaluated based on the 
9 to 11 measurements, which are measured every 10 to 13 samples, during a run 
at the concentration of C-6 std. Summary of precisions are shown as shown in 
Table 3.5.7 and Figures 3.5.8 to 3.5.10, the precisions for each parameter 
are generally good considering the analytical precisions estimated from the 
simultaneous analyses of 14 samples in January 2009 as shown in Table 3.5.6. 
Analytical precisions previously evaluated were 0.18 %for nitrate, 0.14 %for 
phosphate and 0.08 %for silicate, respectively. During this cruise, 
analytical precisions were 0.12 %for nitrate, 0.20 %for phosphate and 0.14 
%for silicate in terms of median of precision, respectively. Then we can 
conclude that the analytical precisions for nitrate, phosphate and silicate 
throughout this cruise became relatively bad. The reasons of the phenomenon 
is discussed in chapter (8).


Table 3.5.7: Summary of precision based on the replicate analyses.

                          Nitrate  Phosphate  Silicate
                           CV %      CV %       CV %
                          -------  ---------  --------
                 Median    0.12      0.20       0.14
                 Mean      0.13      0.21       0.13
                 Maximum   0.4       0.4        0.25
                 Minimum   0.04      0.05       0.05
                 N         102       102        102


Figure 3.5.8: Time series of precision of nitrate for MR11–08.

Figure 3.5.9. Time series of precision of phosphate for MR11–08.

Figure 3.5.10. Time series of precision of silicate for MR11–08.


(7.2) Carry over

We also summarize the magnitudes of carry over throughout the cruise. These 
are small enough within acceptable levels as shown in Table 3.5.8 and Figures 
3.5.11 – 3.5.13.


Table 3.5.8: Summary of carry over through out MR11–08 cruise.

                          Nitrate  Phosphate  Silicate
                           CV %      CV %       CV %
                          -------  ---------  --------
                 Median    0.11      0.19       0.10
                 Mean      0.12      0.21       0.10
                 Maximum   0.33      0.8        0.28
                 Minimum   0.00      0.00       0.00
                 N         102       102        102


Figure 3.5.11: Time series of carryover of nitrate for MR11–08.

Figure 3.5.12: Time series of carryover of silicate for MR11–08.

Figure 3.5.13. Time series of carryover of phosphate for MR11–08.


(7.3) Estimation of uncertainty of phosphate, nitrate and silicate 
      concentrations

Empirical equations, eq. (1), (2) and (3) to estimate uncertainty of 
measurement of phosphate, nitrate and silicate are used based on measurements 
of 140 sets of RMNSs during the this cruise. These empirical equations are as 
follows, respectively.

Phosphate Concentration Cp in μmol kg-1:

    Uncertainty of measurement of phosphate (%) =

        0.14871+ 0.61128 x (1/Cp) + 0.02228 x (1/Cp) x (1/Cp) --- (1)

where Cp is phosphate concentration of sample.


Nitrate Concentration Cn in μmol kg-1:

    Uncertainty of measurement of nitrate (%) =

        0.14629 + 2.5141 x (1/Cn) + 0.056725 x (1/Cn) x (1/Cn) --- (2)

where Cn is nitrate concentration of sample.


Silicate Concentration Cs in μmol kg-1:

    Uncertainty of measurement of silicate (%) =

        0.12394+ 9.9377 x (1/Cs) + 7.6725 x (1/Cs) x (1/Cs) --- (3)

where Cs is silicate concentration of sample.


(8) Problems/improvements occurred and solutions

During this cruse, we observed noisy signals in output of QuAAtro 2-HR 
systems. After this cruise we investigated on this and confirmed that noisy 
signals were originated from Kr-lamps of the colorimeters. We did fix this 
problem by using LED lamps instead of Kr-lamps.



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., 2006: 2003 Intercomparison Exercise for Reference Material for 
    Nutrients in Seawater in a Seawater Matrix, Technical Reports of the 
    Meteorological Research Institute No.50, 91pp, Tsukuba, Japan.

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.

Aoyama M., J. Barwell-Clarke, S. Becker, M. Blum, Braga E. S., S. C. 
    Coverly,E. Czobik, I. Dahllof, M. H. Dai, G. O. Donnell, C. Engelke, G. 
    C. Gong, Gi-Hoon Hong, D. J. Hydes, M. M. Jin, H. Kasai, R. Kerouel, Y. 
    Kiyomono, M. Knockaert, N. Kress, K. A. Krogslund, M. Kumagai, S. 
    Leterme, Yarong Li, S. Masuda, T. Miyao, T. Moutin, A. Murata, N. Nagai, 
    G.Nausch, M. K. Ngirchechol, A. Nybakk, H. Ogawa, J. van Ooijen, H. Ota, 
    J. M. Pan, C. Payne, O. Pierre-Duplessix, M. Pujo-Pay, T. Raabe, K. 
    Saito, K. Sato, C. Schmidt, M. Schuett, T. M. Shammon, J. Sun, T. Tanhua, 
    L. White, E.M.S. Woodward, P. Worsfold, P. Yeats, T. Yoshimura, 
    A. Youenou, J. Z. Zhang, 2008: 2006 Intercomparison Exercise for 
    Reference Material for Nutrients in Seawater in a Seawater Matrix, 
    Technical Reports of the Meteorological Research Institute No. 58, 104pp.

Aoyama, M., Nishino, S., Nishijima, K., Matsushita, J., Takano, A., Sato, K., 
    2010a. Nutrients, In: R/V Mirai Cruise Report MR10-05. JAMSTEC, Yokosuka, 
    pp. 103-122.

Aoyama, M., Matsushita, J., Takano, A., 2010b. Nutrients, In: MR10-06 
    preliminary cruise report. JAMSTEC, Yokosuka, pp. 69-83

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.

Grasshoff, K., Ehrhardt, M., Kremling K. et al. 1983. Methods of seawater 
    anylysis. 2nd rev. Weinheim: Verlag Chemie, Germany, West.

Hydes, D.J., Aoyama, M., Aminot, A., Bakker, K., Becker, S., Coverly, S., 
    Daniel, A., Dickson, A.G., Grosso, O., Kerouel, R., Ooijen, J. van, Sato, 
    K., Tanhua, T., Woodward, E.M.S., Zhang, J.Z., 2010. Determination of 
    Dissolved Nutrients (N, P, Si) in Seawater with High Precision and Inter-
    Comparability Using Gas- Segmented Continuous Flow Analysers, In: GO-SHIP 
    Repeat Hydrography Manual: A Collection of Expert Reports and Guidelines. 
    IOCCP Report No. 14, ICPO Publication Series No 134.

Joyce, T. and Corry, C. 1994. Requirements for WOCE hydrographic programmed 
    data reporting. WHPO Publication, 90-1, Revision 2, WOCE Report No. 
    67/91.

Kawano, T., Uchida, H. and Doi, T. WHP P01, P14 REVISIT DATA BOOK, (Ryoin 
    Co., Ltd., Yokohama, 2009). 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.

Sato, K., Aoyama, M., Becker, S., 2010. RMNS as Calibration Standard Solution 
    to Keep Comparability for Several Cruises in the World Ocean in 2000s. 
    In: Aoyama, M., Dickson, A.G., Hydes, D.J., Murata, A., Oh, J.R., Roose, 
    P., Woodward, E.M.S., (Eds.), Comparability of nutrients in the world’s 
    ocean. Tsukuba, JAPAN: MOTHER TANK, pp 43-56.

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).



3.6  Chlorofluorocarbons and Sulfur Hexafluoride
     September 5, 2013

(1) Personnel

    Ken’ichi Sasaki (MIO, JAMSTEC)
    Katsunori Sagishima (MWJ)
    Shoko Tatamisashi (MWJ)
    Hironori Satoh (MWJ)
    Masahiro Ohrui (MWJ)

(2) Objectives

Chlorofluorocarbons (CFCs) and sulfur hexafluoride (SF6) are man – made 
stable gases. These gases can slightly dissolve in sea surface water by air-
sea gas exchange and then are spread into the ocean interior. These dissolved 
gases could be used as transient chemical tracers for the ocean circulation. 
We measured concentrations of three chemical species of CFCs, CFC-11 (CCl3F), 
CFC-12 (CCl2F2) and CFC-113 (C2Cl3F3), and SF6 in seawater on board.

(3) Apparatuses

Measurement of CFCs and SF6 were made with three gas chromatographs attached 
with purging and trapping systems (modified from the original design of 
Bullister and Weiss (1988)). One was SF6/CFCs simultaneous analyzing system 
(System A). Other two were CFCs analyzing systems (System D and E). These 
purging and trapping systems were developed in JAMSTEC.

(3.1) SF6/CFCs simultaneous analyzing system (System A)

Cold trap columns are 30 cm length stainless steel tubing packed the section 
of 5cm with 100/120 mesh Porapak T and followed by the section of 5cm of 
100/120 mesh Carboxen 1000. Outer diameters of the main and focus trap 
columns are 1/8” and 1/16”, respectively.

A gas chromatograph (GC-14B: Shimadzu LTD) has two electron capture 
detectors, ECD1 and ECD2 (ECD- 14: Shimadzu LTD). A pre-column is Silica Plot 
capillary column [i.d.: 0.32 mm, length: 10 m, film thickness: 4 μm]. There 
are two main analytical columns in GC. Main column 1 (MC1) connected up to 
ECD1 is MS 5A packed column [1/16” OD, 10 cm length stainless steel tubing 
packed the section of 7 cm with 80/100 mesh Molecular Sieve 5A] followed by 
Gas Pro capillary column [i.d.: 0.32 mm, length: 35 m] for SF6 and CFC-12 
analyses. Main column 2 (MC2) connected up to ECD2 is Silica Plot capillary 
column [i.d.: 0.32mm, length: 30 m, film thickness: 4 μm] for CFC-11 and CFC-
113 analyses.

(3.2) CFCs Systems (System D and E)

Cold trap column of the system is 1/16” stainless steel tubing packed with 
5cm of 100/120 mesh Porapak T.

The GCs (GC-14B) in these systems had single ECD (ECD-14), respectively. A 
pre column was Silica Plot capillary column [i.d.: 0.53mm, length: 8 m, film 
thickness: 6μm]. A main column was Pola Bond-Q capillary column [i.d.: 
0.53mm, length: 9 m, film thickness: 10μm] followed by Silica Plot capillary 
column [i. d.: 0.53mm, length: 14 m, film thickness: 6μm]

(4) Shipboard measurements

(4.1) Sampling

The marine water sampler was cleaned by diluted acetone before every CTD cast 
in order to remove any oils which could cause contaminations of CFCs. 
Seawater sub-samples were collected from 12 litter Niskin bottles to 250 ml 
and 400 ml of glass bottles for CFC and SF6 measurements, respectively. CFCs 
sampling was made in every station and SF6 sampling was done in every other 
station. The sub-sampling bottles were filled by nitrogen gas before sub-
sampling. Two times of the bottle volumes of seawater sample were overflowed. 
The bottles filled by seawater samples were kept in thermostatic water bath 
(7ºC). The CFC and SF6 concentrations were determined within 24 hours.

In order to confirm stabilities of standard gases and to check saturation 
levels of CFCs and SF6 in sea surface water, mixing ratios of CFCs and SF6 in 
background air were periodically analyzed. Air samples were continuously led 
into the Environmental Research Laboratory of R/V MIRAI by 10 mm OD Dekaron 
tubing. The end of the tubing was put on a head of the Compass Deck and 
another end was connected onto an air pump in the laboratory. The tubing was 
relayed by a T-type union which had a small stop cock. Air sample was 
collected from the flowing air into a 200 ml glass cylinder attached on the 
cock. Average mixing ratios of the atmospheric CFC- 11, CFC-12, CFC-113, and 
SF6 were 237.7 ± 8.4 ppt, 522.8 ± 7.4 ppt, 71.4 ± 4.4 (n = 100) and 7.36 ± 
0.25 ppt, respectively.

(4.2) Analyses

(4.2.1) SF6/CFCs simultaneous analyses (System A)

Constant volume of sample water (200 ml) was taken into a sample loop. The 
sample was send into stripping chamber and dissolved gases were extracted by 
pure nitrogen gas purging for 9 minutes. The gas sample was dried by 
magnesium perchlorate desiccant and concentrated on a main trap column cooled 
to –80 ºC. Stripping efficiencies were frequently confirmed by re-stripping 
of surface layer samples and more than 99 %of dissolved SF6 and CFCs were 
extracted on the first purge. Following purging & trapping, the main trap 
column was isolated and heated to 170 ºC for 1 minute. The desorbed gases 
were sent onto focusing trap cooled to –80 ºC. Gaseous sample on the focusing 
trap were desorbed by heating to 170 ºC for 1 minute and led into the pre-
column. Sample gases were roughly separated in the pre-column. SF6 and CFC-12 
were sent onto MC1 and CFC-11 and CFC-113 still remain on the pre-column. 
Main column connected up to pre-column was switched to MC2 and another 
carrier gas line was connected up to MC1. SF6 and CFC-12 were further 
separated and detected by the ECD1. CFC-11 and CFC-113 led onto MC 2 were 
detected by ECD2. When CFC-113 eluted from pre-column onto MC 2, the pre-
column was switched onto another line and remaining compounds on the pre-
column were backflushed. Temperature of the analytical column and ECD was 95 
and 300 °C. Mass flow rates of nitrogen gas were 5, 32, 6 and 220 ml/min for 
carrier gases, detector make up gases, back flush gas and sample purging gas, 
respectively. Gas loops whose volumes were 0.05, 0.15, 0.3, 1, 3 and 10 ml 
were used for introducing standard gases into the analytical system. 
Calibration curves were made every several days and standard gas analyses 
using largest loop (10 ml) were performed more frequently to monitor change 
in the detector sensitivity.

(4.2.2) CFCs analyses (System D and E)

These systems were somewhat simple compared with the system A. Volume of 
water sample loop was 50 ml. Gas extraction time was for 8 minutes. Cooling 
and heating temperatures of trap column were –50 and 140 ºC, respectively. 
There were not focusing trap in the systems. Stripping efficiencies were more 
than 99.5 % of dissolved CFCs on the first purge. Temperatures of the 
analytical column and ECD were 95 and 240 °C. Mass flow rates of nitrogen gas 
were 10, 27, 20 and 120 ml/min for carrier, detector make up, back flush and 
sample purging gases, respectively. There were three gas loops whose volumes 
were 1, 3 and 10 ml, respectively.

(4.2.3) Standard gases

The standard gasses had been made by Japan Fine Products co. ltd. Standard 
gas cylinder numbers used in this cruise were listed in Table 3.6.1. Cylinder 
of CPB15651 was used as reference gas. Precise mixing ratios of CFCs/SF6 in 
the standard gases were calculated by gravimetric data. The standard gases 
have not been calibrated to SIO scale standard gases yet because SIO scale 
standard gasses were hard to obtain due to legal difficulties for CFCs import 
into Japan. The data would be corrected as soon as possible when we obtained 
the SIO scale standard gases.

(5) Quality control

(5.1) Interference peak for CFC-113

Analyzing surface layer samples (several hundred meters depth) of tropical 
and sub-tropical region, a large and broad peak was interfered determining 
CFC-113 peak area in chromatograms obtained from system D and E. Retention 
time of the interfering peak was slightly different from that of CFC-113. In 
this case, quality flag “5” was given (no data). The system A completely 
separated the unknown compound from CFC-113 peak. At the SF6 stations, 
measurements of CFC-113 by the system A were adopted.

(5.2) Blanks

Deep water in the North Pacific which would be one of the oldest water masses 
in the world ocean. CFC concentrations in these water masses could be 
considered as overall blanks (from Niskin bottles, sub-sampling, and 
analytical systems). Average concentrations of CFC-11 and CFC-12 in the deep 
water masses (sigma theta > 27.7) were 0.011 ± 0.003, 0.005 ± 0.002 pmol kg–1 
(n = ~700), respectively. These values were assumed as blanks and were 
subtracted from all data. Significant blanks were not found in CFC-113 and 
SF6 measurements.

(5.3) Precisions

The analytical precisions were estimated from replicate sample analyses (N = 
201 pairs for CFC-12 and CFC-11, 166 pairs for CFC-113, and 103 pairs for SF6 
measurements). The replicate samples were collected from two or three 
sampling depths which were around 100, 400 and 600 m depths in every station. 
Precisions were estimated as less than ± 0.007 pmol kg–1 or 0.6 %for CFC-11, 
± 0.004 pmol kg–1 or 0.5 %for CFC-12, ± 0.003 pmol kg–1 or 2 %for CFC-113 
(whichever is greater), and ± 0.05 fmol kg–1 for SF6, respectively. Although 
measurements of CFC-11 and CFC-12 were also obtained from the system A, the 
precisions were somewhat poor ± 0.016 pmol kg–1 for CFC-11 and ± 0.006 pmol 
kg–1 for CFC-12) compared with those of measurement by system D and E. 
Measurements of CFC-11 and CFC-12 from system A were rejected except the 
stations of P10- 004 and P10-006 (because there was not measurements from the 
system D or E).



Reference

Bullister, J.L and Weiss, R.F. Determination of CCl3F and CCl2F2 in seawater 
and air. Deep Sea Research, 35, 839-853 (1988).


Table 3.6.1. Standard gas cylinder list (Japan Fine Products co. ltd.).

                              CFC-11  CFC-12  CFC113   SF6    N2O
      Cylinder No.  Base gas  [ppt]   [ppt]   [ppt]   [ppt]  [ppb]
      ------------  --------  ------  ------  ------  -----  -----
        CPB23379      Air       501    251     40.3    5.02   198
        CPB17172      Air       998    519     90.0   10.0    300
        CPB17174      Air      1499    750    130     10.0    502
        CPB26826      N2        299    160     30.1    0.0      0
        CPB15674      N2        299    160     30.0    0.0      0
        CPB15651      N2        299    159     30.2    0.0      0



3.7  Dissolved Inorganic Carbon (CT)
     October 4, 2013

(1) Personnel

    Akihiko Murata (RIGC/JAMSTEC)
    Yoshiko Ishikawa (MWJ)
    Hatsumi Aoyama (MWJ)
    Makoto Takada (MWJ)

(2) Objectives

Concentrations of CO2 in the atmosphere are now increasing at a rate of 1.9 
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 cruise (MR11-08, revisit of WOCE P10 line) 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-C 
and -D; 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 3000, Nippon ANS, Inc.).

The seawater dispensing system has an auto-sampler (6 ports), which takes 
seawater from a 250 ml borosilicate glass bottle (DURAN®) and dispenses the 
seawater to a pipette of nominal 20 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 C and D) to the coulometer through a dehydrating 
module. Both the systems have a module with two electric dehumidifiers (kept 
at 1−2 °C) and a chemical desiccant (Mg(ClO4)2).

(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 tightly by a polyethylene 
inner cap.

At a chemical laboratory on the ship, a headspace of approx. 3 ml 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 5 °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), 
1.865%CO2 gas in a nitrogen base, seawater samples (6) was programmed to 
repeat. The measurement of 1.865%CO2 gas was made to monitor response of 
coulometer solutions (from UIC, Inc.). For every renewal of coulometer 
solutions, certified reference materials (CRMs, batch 112) provided by Prof. 
A. G. Dickson of Scripps Institution of Oceanography were analyzed. In 
addition, in-house reference materials (RM) (batch Q24 and Q25 for systems C 
and D, respectively) 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 
(batch 112), 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 112.

Temporal variations of RM measurements for one coulometer solution are shown 
in Fig. 3.7.1. From this figure, it is evident that RM measurements had a 
linear trend of ~6 μmol kg-1, implying that measurements of seawater samples 
also have the trend. The trend was also found in temporal changes of 
1.865%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 of batch 112.

The average and standard deviation of absolute values of differences of CT 
analyzed consecutively were 0.7 and 0.5 μmol kg-1 (n=96), and 0.7 and 0.6 
μmol kg-1 (n=85) for legs 1 and 2, respectively. The values for the entire 
cruises were 0.7 and 0.6 μmol kg-1 (n=181).

Figure 3.7.1: Distributions of RM measurements as a function of sequential 
              day for Stns. 21 and 25 during MR11–08.



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.


3.8  Total Alkalinity (AT)
     October 4, 2013

(1) Personnel

    Akihiko Murata (RIGC/JAMSTEC)
    Tomonori Watai (MWJ)
    Ayaka Hatsuyama (MWJ)
    Yasumi Yamada (MWJ)

(2) Objectives

Concentrations of CO2 in the atmosphere are now increasing at a rate of 1.9 
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 cruise (MR11-08, revisit of WOCE P10 line) 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 
Scan, 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 quartz cells, PFA tubes are connected 
to the cells.

A seawater of approx. 42 ml is transferred from a sample bottle (brosilicate 
glass bottle; 130 ml) into the water-jacketed (25 ºC) 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. 42 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 wavelenghts (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):

            +    
pH  = -log[H ]  = 4.2699 + 0.002578(35-S) log((R-0.00131)/(2.3148 0.1299R))  
  T           T

      -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 (0.050002M, 0.50002 M) on land.



(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), 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 112, certified value = 
2223.26 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 of the batch 112.

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. However, 
we experienced some malfunctions of the system during the cruise, which are 
listed in the followings:

(5) Quality control

During the cruise, temporal changes of AT, which originate from analytical 
problems, were monitored by measuring AT of CRM. We found no abnormal 
measurements during the cruises.

On land, after making the measured values of AT comparable to CRM, we 
examined vertical profiles of AT. In doing so, we found systematic 
differences in AT between 2005 and 2011. To quantify the systematic 
differences, we conducted following analyses; first, we took AT observed 
below 2000 dbar from both 2005 and 2011 datasets. The AT data for 2005 were 
obtained by our cruise by the R/V Mirai (MR11-08). Then we selected AT data 
collected in same or close stations for the two cruises, and found 40 pairs 
in total. For the selected data of each cruise, after normalizing to a 
salinity of 35 (nAT), we applied a Piecewise Hermite Interpolating scheme to 
fixed depths to bottom with an interval of 250 dbar : 2250, 2500, 2750 … . 
Next, we compared nAT differences of each depth in respective pairs (Fig. 
3.8.1). The average of the differences was 6.0 ± 2.6 μmol kg-1. Therefore we 
applied a value of 6.0 μmol kg-1 to each AT in 2011.

The average and standard deviation of absolute values of differences of AT 
analyzed consecutively were 0.5 and 0.4 μmol kg-1 (n = 96), and 0.5 and 0.4 
μmol kg-1 (n = 88) for legs 2 and 3, respectively. The combined values were 
calculated to be 0.5 and 0.4 μmol kg-1 (n = 184).


Fig. 3.8.1: Differences of nAT between 1994 (red) and 2009 (blue) at selected 
            stations.



Reference 

Yao, W. and R. H. Byrne (1998): Simplified seawater alkalinity analysis: Use 
    of linear array spectrometers. Deep-Sea Research I 45, 1383-1392.



3.9  pH
     October 12, 2013

(1) Personnel

    Akihiko Murata (RIGC, JAMSTEC)
    Tomonori Watai (MWJ)
    Ayaka Hatsuyama (MWJ)
    Yasumi Yamada (MWJ)

(2) Objectives

Concentrations of CO2 in the atmosphere are now increasing at a rate of 1.9 
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 cruise (MR11-08, revisit of WOCE P10 line) 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 respective wavelengths.

The pH is calculated based on the following equation (Clayton and Byrne, 
1993):

                              A1 / A2 - 0.00691
           pH = pK  + log(------------------------)        (1),
                  2       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. 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® 
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 kept mostly between 1.4 
and 1.6 by adding acid or alkali solution appropriately.

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® tube of a 
peristaltic pump periodically, when a tube deteriorated.

Absorbances of seawater only and seawater + indicator solutions were measured 
11 times each, and the last value was 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.

(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 3.9.1 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 reported values, which 
are the total scale, were set to the values at 25°C by the CO2 system 
calculation using data for pH and CT with K1, K2 from Mehrbach et al. (1973) 
refit by Dickson and Millero (1987).

The average and standard deviation of absolute values of differences of pH 
analyzed consecutively were 0.0006 and 0.0006 pH unit (n = 116), and 0.0008 
and 0.0010 pH unit (n = 109) for legs 1 and 2, respectively. The combined 
values were 0.0007 and 0.0008 pH unit (n = 225). We compared observed pH and 
pH calculated from CT and AT. The average and standard deviation was 0.0102 
and 0.0072 pH unit, respectively. Thus the accuracy of pH was estimated to be 
0.01 pH unit at best.



References

Clayton T. D. and 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.

Dickson A. G. and F. J. Millero (1987): A Comparison of the equilibrium 
    constants for the dissociation of carbonic acid in seawater media. Deep-
    Sea Research 34, 1733-1743.

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.

Mehrbach, C., C. H. Culberson, J. E. Hawley, and R. M. Pytkowicz (1973): 
    Measurement of the apparent dissociation constants of carbonic acid in 
    seawater at atmospheric pressure. Limnology and Oceanography, 18, 897-
    907.

Figure 3.9.1. Perturbation of absorbance ratios by adding indicator 
    solutions. The line was determined by the method of least squares.



3.10  Chlorophyll a
      February 6, 2014

(1) Personnel

    Osamu Yoshida1 (Rakuno Gakuen University) (Principal Investigator)
    Hiroshi Uchida (JAMSTEC) (co-Principal Investigator)
    Yuki Okazaki (Rakuno Gakuen University)
    Shinichi Oikawa (Rakuno Gakuen University)
    Hikari Shimizu (Rakuno Gakuen University)
    Chisato Yoshikawa (Tokyo Institute of Technology /
        Japan Society for the Promotion of Science) (Not on board)
    Shoko Tatamisashi (MWJ)
    Masahiro Orui (MWJ)
    Naohiro Yoshida (Tokyo Institute of Technology) (Not on board)

(2) Sampling elements

The Rakuno Gakuen University (RGU) group collected chlorophyll a samples at 
CTD/CWS stations 1, 29, 45, 58, 71, 88, and 114 for bucket and Niskin bottles 
of 36, 35, 34, 33 and 32. The JAMSTEC collected chlorophyll a samples at 
CTD/CWS stations 2, 9, 15, 19, 24, 59, 62, 65, 68, 77, 79, 82, 84, 90, 94, 
100, 106, and 112 for a Niskin bottle closed near chlorophyll a maximum to 
calibrate CTD fluorometer data. The JAMSTEC also collected chlorophyll a 
samples from the sea surface water monitoring system once in a day at night 
to calibrate the fluorometer of the sea surface water monitoring system.

(3) Objective

Chlorophyll a is one of the most convenient indicators of phytoplankton 
stock, and has been used extensively for the estimation of phytoplankton 
abundance in various aquatic environments. The object of this 83 study is to 
investigate the vertical distribution of phytoplankton in various light 
intensity depth and the horizontal distribution of phytoplankton at sea 
surface along the cruise track.

(4) Materials and methods

Seawater samples were collected 250 mL at 6 depths from surface to about 200 
m with Niskin bottles, except for the Surface water, which was taken by the 
bucket. For JAMSTEC stations, water samples were collected 500 mL bottle. The 
samples were gently filtrated by low vacuum pressure (<0.02 MPa) through 
Whatman GF/F filter (diameter 25 mm) in the dark room. Phytoplankton pigments 
were immediately extracted in 7 mL of N,Ndimethylformamide (DMF) after 
filtration and then, the samples were stored at –20°C under the dark 
condition to extract chlorophyll a for 24 hours or more. The extracted 
samples are measured the fluorescence by Turner fluorometer (10-AU-005, 
TURNER DESIGNS) which was previously calibrated against a pure chlorophyll a 
(Sigma-Aldrich Co.). We applied the fluorometric “Non-acidification method” 
(Welschmeyer, 1994).

(5) Results

The results of chlorophyll a at RGU sampling stations and relationship 
between chlorophyll a concentrations and chlorophyll a estimated from CTD 
fluorometer were shown in Figures 3.10.1 and 3.10.2, respectively.



Reference

Welschmeyer, N. A. (1994): Fluorometric analysis of chlrophyll a in the 
    presence of chlorophyll b and pheopigments. Limnol. Oceanogr., 39, 1985-
    1992.


Figure 3.10.1: Vertical distributions of chlorophyll a at RGU stations.

Figure 3.10.2: Relationship between fluorescent values of seawater and 
               chlorophyll a concentrations at RGU (solid circles) and 
               JAMSTEC (open circles) stations.



3.11  LADCP
      August 13, 2013

(1) Personnel

    Shinya Kouketsu (JAMSTEC)
    Hiroshi Uchida (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 
volts expendable Alkali 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 were Teledyne RD Instruments, WHM300(S/N 
183240).

(3) Data collection

In this cruise, data were collected with the following configuration.

    Bin size: 4 m
    Number of bins: 25
    Pings per ensemble: 1
    Ping interval: 1 sec

(4) Data collection problems

Echo intensities are sufficiently high along the section (Fig. 3.11.1), 
except at the stations of 9. Since the weak echo were observed for all the 
beams, the weakness was not due to the instrument problem.

Figure 3.11.1: Cast-averaged echo intensities at the first bin. Red, blue, 
               green and orange denote beam 1, 2, 3, and 4 respectively.

(5) 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 0.1. GPS 
navigation data and the bottom-track data are used in the calculation of the 
reference velocities. Shipboard ADCP data averaged for 1 minute are also 
included in the calculation. The CTD data are used for the sound speed and 
depth calculation. The directions of velocity are corrected using the 
magnetic deviation estimated with International Geomagnetic reference field 
data.

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.


Station Summary (see PDF version or data files)



Water sample parameters:

       --------------------------------------------------------
       Number  Parameter             Mnemonic  Mnemonic for
                                                 expected error
       --------------------------------------------------------
          1    Salinity              SALNTY
          2    Oxygen                OXYGEN
          3    Silicate              SILCAT    SILUNC  
          4    Nitrate               NITRAT    NRAUNC
          5    Nitrite               NITRIT    NRIUNC
          6    Phosphate             PHSPHT    PHPUNC
          7    Freon-11              CFC-11
          8    Freon-12              CFC-12
          9    Tritium               TRITUM
         12    14Carbon              DELC14    C14ERR
         13    13Carbon              DELC13    C13ERR
         22    137Cs                 CS-137
         23    Total carbon          TCARBN
         24    Total alkalinity      ALKALI
         26    pH                    PH
         27    Freon-113             CFC113
         31    Methane               CH4
         33    Nitrous oxide         N2O
         34    Chlorophyll a         CHLORA
         82    15N-Nitrate           15NO3
         89    134Cs                 CS-134
         90    Perfluorinated acids  
         91    129I                  I-129
         92    Density salinity      DNSSAL
         93    Sulfur hexafluoride   SF6
       --------------------------------------------------------



Figure captions

Figure 1: Station locations for WHP P10 revisit in 2011 cruise with bottom 
          topography based on Smith and Sandwell (1997).

Figure 2: Bathymetry measured by Multi Narrow Beam Echo Sounding system.

Figure 3: Surface wind measured at 25 m above sea level. Wind data is 
          averaged over 6-hour.

Figure 4: (a) Sea surface temperature (°C), (b) sea surface salinity (psu), 
          (c) sea surface oxygen (μmol/kg), and (d) sea surface chlorophyll a 
          (mg/m3) measured by the Continuous Sea Surface Water Monitoring 
          System.

Figure 5: Difference in the partial pressure of CO2 between the ocean and the 
          atmosphere, ΔpCO2.

Figure 6: Surface current at 100 m depth measured by ship board acoustic 
          Doppler current profiler (ADCP).

Figure 7: Potential temperature (°C) cross section calculated by using CTD 
          temperature and salinity data calibrated by bottle salinity 
          measurements. Vertical exaggeration of the 0-6500 m section is 
          1000:1. Expanded section of the upper 1000 m is made with a 
          vertical exaggeration of 2500:1.

Figure 8: CTD salinity (psu) cross section calibrated by bottle salinity 
          measurements. Vertical exaggeration is same as Figure 7.

Figure 9: Absolute salinity (g/kg) cross section calculated by using CTD 
          salinity data. Vertical exaggeration is same as Figure 7.

Figure 10: Density (σ0) (kg/m3) cross section calculated by using CTD 
           temperature and salinity data. Vertical exaggeration is same as 
           Figure 7. (a) EOS-80 and (b) TEOS-10 definition.

Figure 11: Same as Figure 10 but for σ4 (kg/m3). (a) EOS-80 and (b) TEOS-10 
           definition.

Figure 12: Neutral density (γn) (kg/m3) cross section calculated by using CTD 
           temperature and salinity data. Vertical exaggeration is same as 
           Figure 7.

Figure 13: Cross section of CTD oxygen (μmol/kg). Vertical exaggeration is 
           same as Figure 7.

Figure 14: Cross section of CTD chlorophyll a (mg/m3). Vertical exaggeration 
           of the upper 1000 m section is same as Figure 7.

Figure 15: Cross section of bottle sampled dissolved oxygen (μmol/kg). Data 
           with quality flags of 2 were plotted. Vertical exaggeration is 
           same as Figure 7.

Figure 16: Silicate (μmol/kg) cross section. Data with quality flags of 2 
           were plotted. Vertical exaggeration is same as Figure 7.

Figure 17: Nitrate (μmol/kg) cross section. Data with quality flags of 2 were 
           plotted. Vertical exaggeration is same as Figure 7.

Figure 18: Nitrite (μmol/kg) cross section. Data with quality flags of 2 were 
           plotted. Vertical exaggeration of the upper 1000 m section is same 
           as Figure 7.

Figure 19: Phosphate (μmol/kg) cross section. Data with quality flags of 2 
           were plotted. Vertical exaggeration is same as Figure 7.

Figure 20: Dissolved inorganic carbon (μmol/kg) cross section. Data with 
           quality flags of 2 were plotted. Vertical exaggeration is same as 
           Figure 7.

Figure 21: Total alkalinity (μmol/kg) cross section. Data with quality flags 
           of 2 were plotted. Vertical exaggeration is same as Figure 7.

Figure 22: pH cross section. Data with quality flags of 2 were plotted. 
           Vertical exaggeration is same as Figure 7.

Figure 23: CFC-11 (pmol/kg) cross section. Data with quality flags of 2 were 
           plotted. Vertical exaggeration is same as Figure 7.

Figure 24: CFC-12 (pmol/kg) cross section. Data with quality flags of 2 were 
           plotted. Vertical exaggeration is same as Figure 7.

Figure 25: CFC-113 (pmol/kg) cross section. Data with quality flags of 2 were 
           plotted. Vertical exaggeration is same as Figure 7.

Figure 26: Cross section of current velocity (cm/s) normal to the cruise 
           track measured by LADCP (eastward is positive). Vertical 
           exaggeration is same as Figure 7.

Figure 27: Difference in potential temperature (°C) between results from the 
           previous cruise and the revisit in 2011 (December 2011 – February 
           2012). The previous cruise is (a) WOCE (October – November 1993) 
           and (b) the first revisit (May – June 2005). Red and blue areas 
           show 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 7.

Figure 28: Same as Fig. 27, but for salinity (psu). On white areas 
           differences in salinity do not exceed the detection limit of 0.002 
           psu.

Figure 29: Same as Fig. 27, but for dissolved oxygen (μmol/kg). CTD oxygen 
           data were used. On white areas differences in dissolved oxygen do 
           not exceed the detection limit of 2 μmol/kg.

Note

1. As for the traceability of SSW to Kawano’s value (Kawano et al., 2006), 
   the offset for the batches P114 (WOCE P10 stations from 1 to 12), P120 
   (WOCE P10 stations from 13 to 74), and P145 (the revisit in 2005) and P153 
   (the revisit in 2011) are 0.0020, –0.0009, –0.0009 and 0.0004, 
   respectively. The offset values for the recent batches are listed in Table 
   A1 (Uchida et al., in preparation). For P120 of WOCE P10 cruise, salinity 
   was corrected with an offset of –0.0015 (cruise report of WOCE P10). 
   Therefore, the salinity data are corrected with an offset of 0.0006 for 
   the stations from 13 to 74 of WOCE P10.



Table A1. SSW batch to batch differences from P145 to P155 (Uchida et al., in 
          preparation). The difference of P145 is reevaluated.

Batch no.  Production    K15     Sp        Batch to batch difference (x10–3)
             date                        Mantyla’s standard  Kawano’s standard
---------  ----------  -------  -------  ------------------  -----------------
  P145     2004/07/15  0.99981  34.9925         –2.2               –0.9
  P146     2005/05/12  0.99979  34.9917         –2.7               –1.4
  P147     2006/06/06  0.99982  34.9929         –1.8               –0.5
  P148     2006/10/01  0.99982  34.9929         –1.2                0.1
  P149     2007/10/05  0.99984  34.9937         –0.6                0.7
  P150     2008/05/22  0.99978  34.9913         –0.5                0.8
  P151     2009/05/20  0.99997  34.9984         –1.3                0.0
  P152     2010/05/05  0.99981  34.9926         –1.3                0.0
  P153     2011/03/08  0.99979  34.9918         –0.9                0.4
  P154     2011/10/20  0.99990  34.9961         –0.7                0.6
  P155     2012/09/19  0.99981  34.9925         –1.1                0.2



References

Kawano, T., M. Aoyama, T. Joyce, H. Uchida, Y. Takatsuki and M. Fukasawa 
    (2006): The latest batch-to-batch difference table of standard seawater 
    and its application to the WOCE onetime sections, J. Oceanogr., 62, 777–
    792.

Smith, W. H. F. and D. T. Sandwell (1997): Global seafloor topography from 
    satellite altimetry and ship depth soundings, Science, 277, 1956–1962.




CCHDO DATA PROCESSING NOTES

Leg 2 (49NZ20111220)

Date        Person           Data Type   Action          Summary
----------  ---------------  ----------  --------------  -----------------------------------
2012-07-25  Uchida, Hiroshi  CTD/SUM     Submitted       to go online
            Documentation and bottle files will be submitted within a year.

2012-11-21  Staff, CCHDO     CTD/SUM    Website Update  Available under 'Files as received' 
            The following files are now available online under 'Files as received', unprocessed 
            by the CCHDO.

              49NZ20120113_ct1.zip
              49NZ20111220_sum.txt
              49NZ20120113_xct.zip
              49NZ20111220_ct1.zip
              49NZ20120113_sum.txt

2014-05-14  E, S             SUM,CTD     Website Update  Exchange, netCDF, and WOCE files online. 
                                                         CTDPRS,CTDTMP,CTDSAL,CTDOXY,FLUOR,XMISS, 
                                                         XMISSCP,PAR 
            =============================================================================
            P10 2011 49NZ20111220 processing - CTD/SUM - 
            CTDPRS,CTDTMP,CTDSAL,CTDOXY,FLUOR,XMISS,XMISSCP,PAR
            =============================================================================
            2014.05.14
            SE
            .. contents:: :depth: 2

            Submission
            ==========
            =============================== =============== ========== ========== ====
            filename                        submitted by    date       data type  id  
            =============================== =============== ========== ========== ====
            49NZ20111220_sum.txt            Hiroshi Uchida  2012-07-25 SUM        851
            49NZ20111220_ct1.zip            Hiroshi Uchida  2012-07-25 CTD        851
            =============================== =============== ========== ========== ====
            Parameters
            ----------
            49NZ20111220_sum.txt
            ~~~~~~~~~~~~~~~~~~~~
            49NZ20111220_ct1.zip
            ~~~~~~~~~~~~~~~~~~~~
             - CTDPRS [1]_ 
             - CTDTMP [1]_
             - CTDSAL [1]_
             - CTDOXY [1]_
             - FLUOR [1]_
             - XMISS [1]_
             - XMISSCP
             - PAR [1]_
            .. [1] parameter has quality flag column
            Process
            =======
            Changes
            -------
            49NZ20111220_sum.txt
            ~~~~~~~~~~~~~~~~~~~~
            - Kept both "Uncorrected Depth" and "Corrected Depth",  although one is probably   
              incorrect
            - Changed order of first header line,  added timestamp
            49NZ20111220_ct1.zip
            ~~~~~~~~~~~~~~~~~~~~
            - removed last "," from every units line.
            - changed FLUOR units from MG/CUM to MG/M^3 in every units line.
            - Updated header.
            Conversion
            ----------
            ======================= ==================== ========================
            file                    converted from       software
            ======================= ==================== ========================
            49NZ20111220_nc_ctd.zip 49NZ20111220_ct1.zip hydro 0.8.0-117-g2f13399
            ======================= ==================== ========================
            - Exchange and NetCDF files opened in JOA with no apparent problems.
            - Exchange file opened in ODV with no apparent problems.
            Conversion
            ----------
            ======================= ==================== ========================
            file                    converted from       software                
            ======================= ==================== ========================
            49NZ20111220_nc_ctd.zip 49NZ20111220_ct1.csv hydro 0.8.0-117-g2f13399
            ======================= ==================== ========================
            All converted files opened in JOA with no apparent problems.
            Directories
            ===========
            :working directory:
              /data/co2clivar/pacific/p10/p10_49NZ20111220/original/2014.05.14_SUM,CTD_SE
            :cruise directory:
              /data/co2clivar/pacific/p10/p10_49NZ20111220
            Updated Files Manifest
            ======================
            ======================= ================
            file                    stamp           
            ======================= ================
            49NZ20111220_ct1.zip    20140514CCHSIOSE
            49NZ20111220_sum.txt                    
            49NZ20111220_nc_ctd.zip 20140514CCHSIOSE
            ======================= ================

2014-08-18  Key, Bob         BTL         Submitted       to go online 
            8/15/14 
            Downloaded file 49NZ20120113_hy1.csv from 
            http://www.jamstec.go.jp/iorgc/ocorp/data/p10rev_2011/index.html  
            
            8/18/14 
            With eXcel 
            Remove leading “X” from bottle numbers 
            Replace “J” in bottle numbers with “0” 
            Surface samples have bottle “-999” replace with 99 
            Delete CTDPRS_FLAG_W 
            Delete CTDTMP_FLAG_W 
            Delete c13,c14,h3,cs134,cs137 and errors 
            Delete DNSSAL and flag, XMISSCP 
            Delete SILUNC, NRAUNC,PHPUNC 
            Save as P10N.2012.csv 
            Fix line endings with vi and delete extra “,” 
            copy to SUN   
            
            —————————— 
            From original file header  
            BOTTLE,20140213JAMSTECRIGC 
            #Software_Version: whp_btl_exchange.rb_v3.0 (occrp) 
            #ORIGINAL_SUM_FILE: 49NZ20120113_sum.txt Tue Jan 14 11:26:58 +0900 2014 
            #ORIGINAL_HYD_FILE: sea201402120503.csv Thu Feb 13 13:01:28 +0900 2014 
            #DEPTH_TYPE: COR 
            #EVENT_CODE: BO
            
2014-08-19  Staff, CCHDO     BTL/CrsRpt  Website Update  Available under 'Files as received' 
            The following files are now available online under 'Files as received', unprocessed by 
            the CCHDO.
              README.Mac.txt
              49NZ20111220.exc.csv
              p10rev_2011_databook.pdf

2014-09-17  Lee, Rox         BTL         Website Update  Exchange and netCDF files online 
            =============================
            49NZ20111220 processing - BTL
            =============================
            2014-09-17
            R Lee
            .. contents:: :depth: 2
            Submission
            ==========
            ==================== ============= ========== ========== ====
            filename             submitted by  date       data type  id  
            ==================== ============= ========== ========== ====
            49NZ20111220.exc.csv Robert M. Key 2014-08-18 BTL/CrsRpt 1202
            ==================== ============= ========== ========== ====
            Parameters
            ----------
            - CTDPRS
            - CTDTMP
            - CTDSAL [1]_
            - SALNTY [1]_
            - CTDOXY [1]_
            - OXYGEN [1]_
            - SILCAT [1]_
            - NITRAT [1]_
            - NITRIT [1]_
            - PHSPHT [1]_
            - CFC-11 [1]_
            - CFC-12 [1]_
            - CFC113 [1]_
            - SF6 [1]_
            - TCARBN [1]_
            - ALKALI [1]_
            - PH_TOT [1]_
            - PH_TMP
            - XMISS [1]_ [3]_
            - CHLORA [1]_
            - FLUOR [1]_ [3]_
            - PAR [1]_ [3]_
            - THETA [3]_
            - SBE35 [1]_ [3]_
            49NZ20111220.exc.csv
            ~~~~~~~~~~~~~~~~~~~~
            .. [1] parameter has quality flag column
            .. [3] not in WOCE bottle file
            Process
            =======
            Changes
            -------
            - Changed SEB35 to SBE35
            49NZ20111220.exc.csv
            ~~~~~~~~~~~~~~~~~~~~
            Conversion
            ----------
            ======================= ==================== =======================
            file                    converted from       software               
            ======================= ==================== =======================
            49NZ20111220_nc_hyd.zip 49NZ20111220_hy1.csv hydro 0.8.2-40-g569f4c2
            ======================= ==================== =======================
            All converted files opened in JOA with no apparent problems.
            Directories
            ===========
            :working directory:
              /data/co2clivar/pacific/p10/p10_49NZ20111220/original/2014.09.17_BTL_RJL
            :cruise directory:
              /data/co2clivar/pacific/p10/p10_49NZ20111220
            Updated Files Manifest
            ======================
            ======================= =================
            file                    stamp            
            ======================= =================
            49NZ20111220_nc_hyd.zip 20140917SIOCCHRJL
            49NZ20111220_hy1.csv    20140917SIOCCHRJL
            ======================= =================

2014-11-04  Kappa, Jerry    CrsRpt       PDF version online  
            I've placed a new PDF version of the cruise report:  49NZ20111220_do.pdf
            into the directory: http://cchdo.ucsd.edu/data/co2clivar/pacific/p10/p10_49NZ20111220/ 
            It includes all the reports provided by the cruise PIs, summary pages and CCHDO data 
            processing notes, as well as a linked Table of Contents and links to figures, tables 
            and appendices.


Leg 3 (49NZ20120113)


Date        Person           Data Type   Action          Summary
----------  ---------------  ----------  --------------  -----------------------------------
2012-07-25  Uchida, Hiroshi  CTD/SUM     Submitted       to go online
            Documentation and bottle files will be submit within a year.
2012-11-21  Staff, CCHDO  CTD/SUM  Website Update  Available under 'Files as received' 
            The following files are now available online under 'Files as received', unprocessed by 
            the CCHDO.
              49NZ20120113_ct1.zip
              49NZ20111220_sum.txt
              49NZ20120113_xct.zip
              49NZ20111220_ct1.zip
              49NZ20120113_sum.txt
2014-02-12  Berys, Carolina  SUM-CTD     Website Update  SUM and CTD files online 
            =================================
            49NZ20120113 processing - SUM/CTD
            =================================
            2014-02-12
            C Berys
            .. contents:: :depth: 2
            Submission
            ==========
            ==================== ============== ========== ========= ===
            filename             submitted by   date       data type id 
            ==================== ============== ========== ========= ===
            49NZ20120113_ct1.zip Hiroshi Uchida 2012-07-25 CTD/SUM   851
            49NZ20120113_sum.txt Hiroshi Uchida 2012-07-25 CTD/SUM   851
            ==================== ============== ========== ========= ===
            Parameters
            ----------
            49NZ20120113_ct1.zip
            ~~~~~~~~~~~~~~~~~~~~
            - CTDPRS [1]_
            - CTDTMP [1]_
            - CTDSAL [1]_
            - CTDOXY [1]_
            - XMISS [1]_ 
            - FLUORM [1]_ 
            - XMISSCP 
            - PAR [1]_ 
            .. [1] parameter has quality flag column
            .. [2] parameter only has fill values/no reported measured data
            .. [3] not in WOCE bottle file
            .. [4] merged
            Process
            =======
            Changes
            -------
            49NZ20120113_ct1.zip
            ~~~~~~~~~~~~~~~~~~~~
            - SECT changed to SECT_ID
            - comma removed form units line
            - FLUOR changed to FLUORM, units changed form MG/CUM to MG/M^3
            - NOTE: files with CTDPRS below 6,000 DBAR did not open in joa
            49NZ20120113_sum.txt
            ~~~~~~~~~~~~~~~~~~~~
            - renamed to 49NZ20120113su.txt
            Conversion
            ----------
            ======================= ==================== =======================
            file                    converted from       software               
            ======================= ==================== =======================
            49NZ20120113_nc_ctd.zip 49NZ20120113_ct1.zip hydro 0.8.0-96-g8497d06
            ======================= ==================== =======================
            All converted files opened in JOA with no apparent problems.
            Directories
            ===========
            :working directory:
              /data/co2clivar/pacific/p10/p10_49NZ20120113/original/2014.02.12_SUM-CTD_CBG
            :cruise directory:
              /data/co2clivar/pacific/p10/p10_49NZ20120113
            Updated Files Manifest
            ======================
            ======================= ===================
            file                    stamp              
            ======================= ===================
            49NZ20120113_nc_ctd.zip                    
            49NZ20120113_ct1.zip    20120525JAMSTECRIGC
            49NZ20120113su.txt                         
            ======================= ===================
2014-08-18  Key, Bob         BTL         Submitted       to go online 
            8/15/14
            Downloaded file 49NZ20120113_hy1.csv from
            http://www.jamstec.go.jp/iorgc/ocorp/data/p10rev_2011/index.html
            8/18/14
            With eXcel
            Remove leading "X" from bottle numbers
            Replace "J" in bottle numbers with "0"
            Surface samples have bottle "-999" replace with 99
            Delete CTDPRS_FLAG_W
            Delete CTDTMP_FLAG_W
            Delete c13,c14,h3,cs134,cs137 and errors
            Delete DNSSAL and flag, XMISSCP
            Delete SILUNC, NRAUNC,PHPUNC
            Save as P10N.2012.csv
            Fix line endings with vi and delete extra ","
            copy to SUN
            __________
            
            From original file header
            
            BOTTLE,20140213JAMSTECRIGC
            #Software_Version: whp_btl_exchange.rb_v3.0 (occrp)
            #ORIGINAL_SUM_FILE: 49NZ20120113_sum.txt Tue Jan 14 11:26:58 +0900 2014
            #ORIGINAL_HYD_FILE: sea201402120503.csv Thu Feb 13 13:01:28 +0900 2014
            #DEPTH_TYPE: COR
            #EVENT_CODE: BO
2014-08-19  Staff, CCHDO    BTL          Website Update  Available under 'Files as received' 
            The following files are now available online under 'Files as received', unprocessed by 
            the CCHDO.
              49NZ20120113.exc.csv
              README.Mac.txt
2014-11-04  Kappa, Jerry    CrsRpt       PDF version online  
            I've placed a new PDF version of the cruise report:  49NZ20120113_do.pdf
             into the directory: http://cchdo.ucsd.edu/data/co2clivar/pacific/p10/p10_49NZ20120113/ 
            It includes all the reports provided by the cruise PIs, summary pages and CCHDO data 
             processing notes, as well as a linked Table of Contents and links to figures, tables 
             and appendices.

2014-09-17  R Lee           BTL          Website Update  Exchange and netCDF files online
            Rox Lee  49NZ20111220 processing - BTL
            2014-09-17
            
            Contents
            * Submission
            o Parameters
            * Process
            o Changes
            o Conversion
            * Directories
            * Updated Files Manifest

            Submission
            filename              submitted by   date        data type   id
            --------------------  -------------  ----------  ----------  ----
            49NZ20111220.exc.csv  Robert M. Key  2014-08-18  BTL/CrsRpt  1202

            Parameters
             * CTDPRS
             * CTDTMP
             * CTDSAL [1]
             * SALNTY [1]
             * CTDOXY [1]
             * OXYGEN [1]
             * SILCAT [1]
             * NITRAT [1]
             * NITRIT [1]
             * PHSPHT [1]
             * CFC-11 [1]
             * CFC-12 [1]
             * CFC113 [1]
             * SF6 [1]
             * TCARBN [1]
             * ALKALI [1]
             * PH_TOT [1]
             * PH_TMP
             * XMISS [1] [3]
             * CHLORA [1]
             * FLUOR [1] [3]
             * PAR [1] [3]
             * THETA [3]
             * SBE35 [1] [3]
            49NZ20111220.exc.csv
            [1]  (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20) parameter has quality flag column
            [3]  (1, 2, 3, 4, 5) not in WOCE bottle file

            Process
            Changes
             * Changed SEB35 to SBE35
            49NZ20111220.exc.csv

            Conversion
            file                     converted from        software
            -----------------------  --------------------  -----------------------
            49NZ20111220_nc_hyd.zip  49NZ20111220_hy1.csv  hydro 0.8.2-40-g569f4c2

            All converted files opened in JOA with no apparent problems.

            Directories
            working directory:
               /data/co2clivar/pacific/p10/p10_49NZ20111220/original/2014.09.17_BTL_RJL
            cruise directory:
               /data/co2clivar/pacific/p10/p10_49NZ20111220

            Updated Files Manifest
            file                     stamp
            -----------------------  -----------------
            49NZ20111220_nc_hyd.zip  20140917SIOCCHRJL
            49NZ20111220_hy1.csv     20140917SIOCCHRJL

2015-03-06  Kappa, Jerry    CrsRpt       TXT version online  
            I've placed a new TEXT version of the cruise report:  49NZ20120113_do.txt
             onto the CCHDO website
            It includes all the reports provided by the cruise PIs, summary pages and CCHDO data 
             processing notes.
