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CRUISE REPORT: P21
(Updated NOV 2011)



HIGHLIGHTS

                               CRUISE SUMMARY INFORMATION

          WOCE Section Designation  P21 leg 1                P21 Leg 2
Expedition designation (ExpoCodes)  49NZ20090410             49NZ20090521
                  Chief Scientists  Akihiko Murata/JAMSTEC   Hiroshi Uchida/JAMSTEC
                             Dates  2009-04-10 - 2009-05-19  2009-05-21 - 2009-06-19
                              Ship  R/V Mirai                R/V Mirai
                     Ports of call  Valparaiso, Chile -      Papeete, Tahiti -
                                    Papeete, Tahiti          Brisbane, Australia

                                                  15° 29.52'S
             Geographic Boundaries  153° 44.52'E               75° 09.86'W
                                                  24° 59.81'S

                          Stations  140                       117
      Floats and drifters deployed  5 Argo floats             0
    Moorings deployed or recovered  0                         0


                               Recent Contact Information:

                    Akihiko Murata                       Hiroshi Uchida
             akihiko.murata@jamstec.go.jp             huchida@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: +81-46-867-9455










                                                       WHP P21 REVISIT DATA BOOK


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

WHP P21 REVISIT DATA BOOK

March 25, 2011 Published
Edited by Hiroshi Uchida (JAMSTEC), 
Akihiko Murata (JAMSTEC) and Toshimasa Doi (JAMSTEC)

Published by © JAMSTEC, Yokosuka, Kanagawa, 2011
Japan Agency for Marine-Earth Science and Technology
2-15 Natsushima, Yokosuka, Kanagawa. 237-0061, Japan
Phone +81-46-867-9474, Fax +81-46-867-9455

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, H. Uchida and K Sasaki (JAMSTEC)
2.  Underway Measurements
    2.1  Navigation and Bathymetry         
         S. Okumura (GODI) et al., T Matsumoto (Univ. Ryukyu) et al.
    2.2  Surface Meteorological Observation         
         K Yoneyama (JAMSTEC) et al.
    2.3  Thermo-Salinograph and Related Measurements         
         Y Kumamoto (JAMSTEC) et al.
    2.4  Underway pCO2        
         A. Murata (JAMSTEC) et al.
    2.5  Acoustic Doppler Current Profiler         
         S. Kouketsu (JAMSTEC) et al.
    2.6  XCTD            
         H. Uchida (JAMSTEC) et al.
3.  Hydrographic Measurement Techniques and Calibrations
    3.1  CTDO2 Measurements         
         H. Uchida (JAMSTEC) et al.
    3.2  Bottle Salinity        
         T Kawano (JAMSTEC) et al.
    3.3  Oxygen        
         Y Kumamoto (JAMSTEC) et al.
    3.4  Nutrients        
         M Aoyama (MRI/JMA) et al.
    3.5  Chlorofluorocarbons (CFCs)         
         K Sasaki (JAMSTEC) et al.
    3.6  Dissolved Inorganic Carbon (CT)         
         A. Murata (JAMSTEC) et al.
    3.7  Total Alkalinity (AT) ..         
         A. Murata (JAMSTEC) et al.
    3.8  pH (pHT)         
         A. Murata (JAMSTEC) et al.
    3.9  LADCP         
         S. Kouketsu (JAMSTEC) et al.

Figures (see PDF doc)
Figure captions 		
Station locations 		
Bathymetry 		
Surface wind 		
Sea surface temperature  		
Sea surface salinity  		
∆pCO2 		
Surface current  		

Cross-sections
Potential temperature  		
CTD salinity 		
Absolute salinity  		
Density (σ0) 		
Density (σ4) 		
Density(γn) 		
CTD oxygen 		
Bottle sampled oxygen  		
Silicate 		
Nitrate 		
Nitrite 		
Phosphate 		
Dissolved inorganic carbon (CT)  		
Total alkalinity (AT)  		
pH (pHT) 		
CFC-11 		
CFC-12 		
CFC -113 		
Velocity 		

Difference between WOCE and the revisit
Potential temperature  		
Salinity  		
CTD oxygen  		

CCHDO Data Processing Notes	





PREFACE

P21 was the WOCE one time survey line located slightly in the south of the 
boundary between two gyre systems of the Equatorial Counter Current and the 
South Equatorial Current. In 1994, WOCE hydrographic observations were 
carried out by United States along the line. After this cruise, P21 was not 
revisited though there is a great possibility that repeat observations along 
this line could detect decadal or long-time scale variability of low 
latitudinal gyre system.

In 2008, the research system of JAMSTEC was re-organized. As the result, 
Institute of Observational Research for Global Change (IORGC) and Frontier 
Research Center for Global Change (FRCGC) were merged to form a new research 
organization of Research Institute for Global Change (RIGC). The General 
Ocean Circulation Research Program of former IORGC, which had been the main 
driver of CLIVAR Carbon Repeat Hydrography (CCRH) in Japan, was also 
developed into the Ocean Climate Change Research Program of new RIGC 
including Argo Group of former IORGC and Ocean assimilation Group of former 
FRCGC together.

P21 revisit cruise reported in this data book was the first CCRH cruise 
carried out under the new program of the Ocean Climate Change Research 
Program of RIGC. Also, it may be better to note here that this revisit-cruise 
was planned and proposed by bio-geochemical oceanographer in the program. One 
of distinct scientific outcomes from bio-geochemical researchers in the 
program was the discovery of the considerable acceleration in the CO2 
up-taking ratio and rapid increase in CO2 accumulation of the South Pacific 
during these decades. P01, P02, P03, P10, P06 and P14 data were analyzed 
comprehensively but the Equator-ward extent of the CO2 related issues 
mentioned above were left to be examined. So, this is the biggest reason why 
P21 was selected to be revisited in spite of the fact that P21 was not 
included in the recommended repeat line in the strategy of the Global Ocean 
Ship-Based Hydrographic Investigation Program (GOSHIP).

After OceanObs09 in Venice, quite a few discussions were held on the 
sustainability of ocean observation and many proposals were published. GOSHIP 
strategy, which had been discussed since 2008 and was adopted in 2010 
finally, is one of answers to those discussions and proposals. The basic and 
important concept of the strategy is to maintain some of WOCE hydrographic 
lines by repeat observations along them as a strong tool of ocean monitoring 
to detect decadal changes in the global oceanic conditions especially in the 
Meridional Overturn Circulation System. We, ocean climate researchers in 
JAMSTEC, have carried out revisit cruises along eight WOCE one-time lines so 
far. However, as long as our activity concerns, P01 is the only line where we 
repeated observations twice. I strongly hope and believe that we will be able 
to have repeat observation along all of eight lines in near future to make 
the strategy of GO-SHIP real and effective.



On the day of Japan Northern Territory*

                                                               Masao Fukasawa 
                                            Research Director of RIGC/JAMSTEC


* On 7th February 1855, The Japan-Russia Treaty of Peace and Amity was 
  ratified in which Etorofu, Kunashiri, Sikotan and Habomai islands are 
  defined as Japan territory.




1   CRUISE NARRATIVE


1.1   HIGHLIGHT

GHPO Section Designation:  P21
Cruise code:               MR09-01
Expedition Designation:    49NZ20090410
                           49NZ20090521

Chief Scientists and Affiliation:

        Leg.1: Akihiko Murata
               akihiko.murata@jamstec.go.jp
        Leg.2: Hiroshi Uchida
               huchida@jamstec.go.jp
        Leg.3: Kenichi Sasaki
               ksasaki@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: +81-46-867-9455

               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: +81-46-867-9455

Ship:          R/V Mirai

Ports of Call: Leg 1:  Valparaiso, Chile - Papeete, Tahiti
               Leg 2a: Papeete, Tahiti - Papeete, Tahiti
               Leg 2b: Papeete, Tahiti - Brisbane, Australia
               Leg 3:  Brisbane, Australia - Moji, Japan

Cruise Dates:  Leg 1:  April 10, 2009 - May 19, 2009
               Leg 2a: May 21, 2009 - May 24, 2009
               Leg 2b: May 25, 2009 - June 19, 2009
               Leg 3:  June 20, 2009 - July 3, 2009

Number of Stations: 257 stations for CTD/Carousel Water Sampler
                    (Leg 1: 140, Leg 2a: 8, Leg 2b: 109)

Geographic Boundaries (for hydrographic stations): 24° 59.81' S - 15° 29.52' S
                                                   153° 44.52' E - 75° 09.86' W
Floats and Drifters Deployed:                      5 Argo floats
Mooring Deployed or Recovered Mooring:             None




1.2   CRUISE SUMMARY


(1) Station occupied

A total of 257 stations was occupied using a Sea-Bird Electronics 36 position 
carousel equipped with 12 litter Niskin-X water sample bottles, a SBE 
9/11plus equipped with SBE35 deep ocean standards thermometer, SBE43 oxygen 
sensor, AANDERAA Optode 3830 and 4330F oxygen sensors, JFE Alec RINKO oxygen 
sensor, Seapoint Sensors fluorometer, WET labs C-Star transmissometer, 
Benthos altimeter, and RDI ADCP. XCTDs were deployed at 23 stations. XMPs 
(eXpendable Microstructure Profiler) were also deployed at 3 stations. Cruise 
track and station location are shown in Figure 1.2.1.


(2) Sampling and measurements

Water samples were analyzed for salinity, oxygen, nutrients, CFC-11, -12, 
-113, total alkalinity, DIC, and pH. The sampling layers are coordinated as 
so-called staggered mesh. Samples for 14C, 13C, methane, nitrous oxide, 
carbonyl sulfide, chlorophyll a, PON, POC, 15N-nitrate, ammonia, and a 
biological study were also collected at the selected stations. The bottle 
depth diagram is shown in Figure 1.2.2. Underway pCO2, temperature, salinity, 
oxygen, surface current, bathymetry, and meteorological measurements were 
conducted along the cruise track.


(3) Floats deployment

Five ARGO floats were launched along the cruise track. The launched positions 
of the ARGO floats are listed in Table 1.2.1.


Table 1.2.1:  Launched positions of the ARGO floats.  
   _______________________________________________________________________

   Float  ARGOS  Date and time    Date and time   Location        CTD 
    S/N    ID    of reset (UTC)  of launch (UTC)  of launch    station no.
   -----  -----  --------------  ---------------  -----------  -----------
   4099   86536    2009/05/01      2009/05/01      16-45.21 S    P21-080
                      18:45           20:03       105-20.41 W     
   4042   86510    2009/05/03      2009/05/03      16-44.51 S    P21-087
                      08:16           09:15       107-19.90 W     
   4101   86537    2009/05/04      2009/05/04      16-45.05 S    P21-095
                      05:54           06:35       109-59.34 W     
   4043   86511    2009/05/05      2009/05/05      16-44.99 S    P21-099
                      04:05           04:52       112-41.19 W     
   4102   86538    2009/05/05      2009/05/05      16-45.33 S    P21-102
                      18:37           19:37       114-40.55 W    
   _______________________________________________________________________


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)             Shinya Okumura (GODI) (leg 1)
               skouketsu@jamstec.go.jp             Satoshi Okumura (GODI) (leg 2)
                                                   Souichiro Sueyoshi (GODI) (leg 3)
Bathymetry   Takeshi Matsumoto (Univ. of Ryukyus)  Shinya Okumura (GODI) (leg 1)
               tak@sci.u-ryukyu.ac.jp              Satoshi Okumura (GODI) (leg 2)
             Masao Nakanishi (Chiba Univ.)         Souichiro Sueyoshi (GODI) (leg 3)
               nakanisi@earth.s.chiba-u.ac.jp  
Meteorology  Kunio Yoneyama (JAMSTEC)              Shinya Okumura (GODI) (leg 1)
               yoneyamak@jamstec.go.jp             Satoshi Okumura (GODI) (leg 2)
                                                   Souichiro Sueyoshi (GODI) (leg 3)
T-S          Yuichiro Kumamoto (JAMSTEC)           Miyo Ikeda (MWJ) (leg 1, 2)
               kumamoto@jamtec.go.jp               Fuyuki Shibata (MWJ) (leg 3)
pCO2         Akihiko Murata (JAMSTEC)              Minoru Kamata (MWJ) (leg 1, 2)
               akihiko.murata@jamstec.go.jp        Yasuhiro Arii (MWJ) (leg 3)
    
HYDROGRAPHY    
    
CTD/O2       Hiroshi Uchida (JAMSTEC)              Kenichi Katayama (MWJ) (leg 1)
               huchida@jamstec.go.jp               Tomoyuki Takamori (MWJ) (leg 2)
XCTD         Hiroshi Uchida (JAMSTEC)              Shinya Okumura (GODI) (leg 1)
               huchida@jamstec.go.jp               Satoshi Okumura (GODI) (leg 2)
LADCP        Shinya Kouketsu (JAMSTEC)             Shinya Kouketsu (JAMSTEC) (leg 1)
               skouketsu@jamstec.go.jp             Katsuro Katsumata (JAMSTEC) (leg 2)
Salinity     Takeshi Kawano (JAMSTEC)              Tatsuya Tanaka (MWJ) (leg 1)
               kawanot@jamstec.go.jp               Fujio Kobayashi (MWJ) (leg 2)
Oxygen       Yuichiro Kumamoto (JAMSTEC)           Fuyuki Shibata (MWJ) (leg 1)
               kumamoto@jamstec.go.jp              Miyo Ikeda (MWJ) (leg 2)
Nutrients    Michio Aoyama (MRI)  Ayumi            Takeuchi (MWJ) (leg 1)
               maoyama@mri-jma.go.jp               Junji Matsushita (MWJ) (leg 2)
DIC          Akihiko Murata (JAMSTEC)              Minoru Kamata (MWJ)
               akihiko.murata@jamstec.go.jp  
Alkalinity   Akihiko Murata (JAMSTEC)              Tomonori Watai (MWJ) (leg 1)
               akihiko.murata@jamstec.go.jp        Yoshiko Ishikawa (MWJ) (leg 2)
pH           Akihiko Murata (JAMSTEC)              Tomonori Watai (MWJ) (leg 1)
               akihiko.murata@jamstec.go.jp        Yoshiko Ishikawa (MWJ) (leg 2)
CFCs         Kenichi Sasaki (JAMSTEC)              Kenichi Sasaki (JAMSTEC)
               ksasaki@jamstec.go.jp  
∆14C/δ13C    Yuichiro Kumamoto (JAMSTEC)           Yuichiro Kumamoto (JAMSTEC)
               kumamoto@jamstec.go.jp  
N2O/CH4      Osamu Yoshida (RGU)                   Osamu Yoshida (RGU) (leg 1)
               yoshida@rakuno.ac.jp                Sakae Toyoda (TITECH) (leg 2)
Biology      Ken Furuya (UT)                       Taketoshi Kodama (UT)
               furuya@fs.a.u-tokyo.ac.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.
      RGU      Rakuno Gakuen University
      TITECH   Tokyo Institute of Technology
      UT       The University of Tokyo



1.4   SCIENTIFIC PROGRAM AND METHODS


(1) Nature and objectives of MR09-01 cruise project

It is well known that climate changes of a timescale more than a decade are 
influenced by changes of oceanic conditions. Among a lot of oceanic changes, 
we focus on transport and accumulation of anthropogenic CO2 and heat in the 
ocean, both of which are important for global warming. Accordingly we are 
aimed at clarifying temporal changes of the transport and accumulation 
quantitatively. In doing so, we pay a special attention to water masses of 
the Southern Ocean's origin, which play an important role in transporting 
anthropogenic CO2 and heat into the ocean's interior. With this purpose, we 
have so far re-occupied historical observation lines, mainly in the Pacific 
Ocean.

This cruise is a reoccupation of the hydrographic section called 'WHP-P21', 
which was observed by an ocean science group of United States of America 
(USA) in 1994 as a part of World Ocean Circulation Experiment (WOCE). The 
dataset is included in the data base of Climate Variability and 
Predictability (CLIVAR) and Carbon Hydrographic Data Office 
(http://whpo.ucsd.edW). We will compare physical and chemical properties 
along section WHP-P21 with those obtained in 1994 to detect and evaluate 
long-term changes of the marine environment in the Pacific.

Reoccupations of the WOCE hydrographic sections are now in progress by 
international cooperation in ocean science community, under the framework of 
CLIVAR, which is as part of World Climate Research Programme (WCRP) and 
International Ocean Carbon Coordination Project (IOCCP). Our research is 
planned as a contribution to this international projects supported by World 
Meteorological Organization (WMO), International Council for Science (ICSU) / 
Scientific Committee on Oceanic Research (SCOR) and United Nations 
Educational, Scientific and Cultural Organization (UNESCO)/Intergovernmental 
Oceanographic Commission (IOC), and the results and data will be published by 
2010 for worldwide use.

The other purposes of this cruise are as follows:

1) to observe surface meteorological and hydrological parameters as a basic 
   data of meteorology and oceanography such as studies on flux exchange, 
   air-sea interaction and so on,
2) to observe sea bottom topography, gravity and magnetic fields along the 
   cruise track to understand the dynamics of ocean plate and accompanying 
   geophysical activities,
3) to observe biogeochemical parameters to study material (carbon, nitrate, 
   etc) cycle in the ocean,
4) to observe greenhouse gases in the atmosphere and the ocean to study their 
   cycle from bio-geochemical aspect, and 
5) to estimate diapycnal diffusitivity in the deep ocean.


(2) Cruise narrative

R/V Mirai departed Valparaiso, Chile on April 10, 2009. The hydrographic cast 
was started at the station P21-29 on April 14, since permission of 
observation in the Peru's EEZ was not yet given. After the CTD station 
P21-33, R/V Mirai sailed towards the station P21-14 off Peru and waited for a 
few days in the Peru's EEZ. XCTDs were deployed at stations from P21-29 to 
P21-33 and the hydrographic cast was restarted at the station P21-41 on April 
21.

At Papeete, Tahiti on 21 May, 2009, 34 crews and scientists who came from 
Japan to embark on R/V Mirai by the same plane were not allowed to embark for 
7 days, because one of the scientists developed a fever of 38°C and was 
suspected as a new type of flu. Therefore, we conducted 8 CTD stations 
without the 34 crews and scientists during leg 2a from 21 to 24 May. Then R/V 
Mirai departed Papeete again on May 25 and we conducted the rest of the 
hydrographic observations in leg 2b. R/V Mirai arrived at Brisbane, Australia 
on June 19, 2009.

During leg 3 from June 20 to July 3, underway observations were conducted 
along the cruise track.



1.5   LIST OF CRUISE PARTICIPANTS


Table 1.5.1(a):  List of cruise participants for leg 1.
__________________________________________________________________________________

NAME                    RESPONSIBILITY                               AFFILIATION
----------------------  -------------------------------------------  -------------
Akihiko Murata          Chief scientist/carbon/water sampling        RIGC/JAMSTEC
Hiroshi Uchida          CTD/water sampling                           RIGC/JAMSTEC
Sinya Kouketsu          LADCP/ADCP/water sampling                    RIGC/JAMSTEC
Yuichiro Kumamoto       DO/thermosalinograph/∆14C                    RIGC/JAMSTEC
Kenichi Sasaki          CFCs                                         MIO/JAMSTEC
Hirokatsu Uno           CTD/water sampling                           MWJ
Kenichi Katayama        CTD/water sampling                           MWJ
Shinsuke Toyoda         CTD/water sampling                           MWJ
Hiroyuki Hayashi        CTD/water sampling                           MWJ
Tatsuya Tanaka          Salinity                                     MWJ
Akira Watanabe          Salinity                                     MWJ
Fuyuki Shibata          DO/water sampling                            MWJ
Miyo Ikeda              DO/water sampling                            MWJ
Misato Kuwahara         DO/water sampling                            MWJ
Shinichiro Yokogawa     Nutrients                                    MWJ
Ayumi Takeuchi          Nutrients                                    MWJ
Kohei Miura             Nutrients                                    MWJ
Kenichiro Sato          Chief technologist/nutrients/water sampling  MWJ
Ai Ueda                 Water sampling                               MWJ
Tetsuo Aoki             Water sampling                               MWJ
Rui Asakawa             Water sampling                               MWJ
Masashi Inose           Water sampling                               MWJ
Shinya Iwasaki          Water sampling                               MWJ
Masahiro Orui           Water sampling                               MWJ
Yuichi Sonoyama         CFCs                                         MWJ
Katsunori Sagishima     CFCs                                         MWJ
Shoko Tatamisashi       CFCs                                         MWJ
Tomonori Watai          pH/total alkalinity                          MWJ
Ayaka Hatsuyama         pH/total alkalinity                          MWJ
Minoru Kamata           DIC                                          MWJ
Yoshiko Ishikawa        DIC                                          MWJ
Shinya Okumura          Meteorology/geophysics/ADCP/XCTD             GODI
Ryo Kimura              Meteorology/geophysics/ADCP/XCTD             GODI
Yosuke Yuki             Meteorology/geophysics/ADCP/XCTD             GODI
Takuhei Shiozaki        Biology/water sampling                       UT
Satoshi Kitajima        Biology/water sampling                       UT
Taketoshi Kodama        Biology/water sampling                       UT
Hiroyuki Kurotori       Biology/water sampling                       UT
Osamu Yoshida           CH4 and N2O/water sampling                   RGU
Sho Imai                CH4 and N2O/water sampling                   RGU
Chiho Kubota            CH4 and N2O/water sampling                   RGU
Wolfgang Schneider      CTD/water sampling                           COPAS
Lorena Graciela         Observer                                     Peruvian Navy
Marquez Ismodes
__________________________________________________________________________________
    COPAS    Center for Oceanographic Research in the eastern South Pacific,
             University of Concepcion, Chile
    GODI     Global Ocean Development Inc.
    JAMSTEC  Japan Agency for Marine-Earth Science and Technology
    MIO      Mutsu Institute of Oceanography
    MWJ      Marine Works Japan, Ltd.
    RGU      Rakuno Gakuen University
    RIGC     Research Institute for Global Change
    UT       The University of Tokyo



Table 1.5.1(b):  List of cruise participants for leg 2a.
__________________________________________________________________________________

NAME                    RESPONSIBILITY                               AFFILIATION
----------------------  -------------------------------------------  -------------
Hiroshi Uchida          Chief Scientist/CTD/water sampling           RIGC/JAMSTEC
Shinya Kouketsu         LADCP/ADCP/water sampling                    RIGC/JAMSTEC
Yuichiro Kumamoto       DO/thermosalinograph /∆14C                   RIGC/JAMSTEC
Toshimasa Doi           LADCP/water sampling                         RIGC/JAMSTEC
Katsuro Katsumata       XMP/LADCP/water sampling                     RIGC/JAMSTEC
Kenichi Sasaki          CFCs                                         MIO/JAMSTEC
Hirokatsu Uno           CTD/water sampling                           MWJ
Kenichi Katayama        CTD/water sampling                           MWJ
Shinsuke Toyoda         CTD/water sampling                           MWJ
Hiroyuki Hayashi        CTD/water sampling                           MWJ
Tatsuya Tanaka          Salinity                                     MWJ
Akira Watanabe          Salinity                                     MWJ
Fuyuki Shibata          DO/water sampling                            MWJ
Miyo Ikeda              DO/water sampling                            MWJ
Misato Kuwahara         DO/water sampling                            MWJ
Shinichiro Yokogawa     Nutrients                                    MWJ
Ayumi Takeuchi          Nutrients                                    MWJ
Kohei Miura             Nutrients                                    MWJ
Kenichiro Sato          Chief technologist/nutrients/water sampling  MWJ
Ai Ueda                 Water sampling                               MWJ
Yuichi Sonoyama         CFCs                                         MWJ
Katsunori Sagishima     CFCs                                         MWJ
Shoko Tatamisashi       CFCs                                         MWJ
Tomonori Watai          pH/total alkalinity                          MWJ
Ayaka Hatsuyama         pH/total alkalinity                          MWJ
Minoru Kamata           DIC                                          MWJ
Yoshiko Ishikawa        DIC                                          MWJ
Shinya Okumura          Meteorology/geophysics/ADCP/XCTD             GODI
Ryo Kimura              Meteorology/geophysics/ADCP/XCTD             GODI
Yosuke Yuki             Meteorology/geophysics/ADCP/XCTD             GODI
Takuhei Shiozaki        Biology/water sampling                       UT
Satoshi Kitajima        Biology/water sampling                       UT
Taketoshi Kodama        Biology/water sampling                       UT
Hiroyuki Kurotori       Biology/water sampling                       UT
Sho Imai                CH4 and N2O/water sampling                   RGU
Chiho Kubota            CH4 and N2O/water sampling                   RGU
Wolfgang Schneider      CTD/water sampling                           COPAS
Camillia Pauline Garae  Observer                                     DGMWR
Harish Pratap           Observer                                     FMS
__________________________________________________________________________________
    DGMWR  Department of Geology Mines and Water Resources, Vanuatu
    FMS    Fiji Meteorological Services, Fiji



Table 1.5.1(c):  List of cruise participants for leg 2b.
__________________________________________________________________________________

NAME                    RESPONSIBILITY                               AFFILIATION
----------------------  -------------------------------------------  -------------
Hiroshi Uchida          Chief scientist/CTD/water sampling           RIGC/JAMSTEC
Yuichiro Kumamoto       DO/thermosalinograph/∆14C                    RIGC/JAMSTEC
Toshimasa Doi           LADCP/water sampling                         RIGC/JAMSTEC
Katsuro Katsumata       XMP/LADCP/water sampling                     RIGC/JAMSTEC
Kenichi Sasaki          CFCs                                         MIO/JAMSTEC
Fujio Kobayashi         Salinity                                     MWJ
Akira Watanabe          Salinity                                     MWJ
Miyo Ikeda              DO/water sampling                            MWJ
Misato Kuwahara         DO/water sampling                            MWJ
Masanori Enoki          DO/water sampling                            MWJ
Ayumi Takeuchi          Nutrients                                    MWJ
Kohei Miura             Nutrients                                    MWJ
Junji Matsushita        Nutrients                                    MWJ
Satoshi Ozawa           Chief technologist/CTD/water Sampling        MWJ
Ai Ueda                 Water sampling                               MWJ
Yuichi Sonoyama         CFCs                                         MWJ
Katsunori Sagishima     CFCs                                         MWJ
Shoko Tatamisashi       CFCs                                         MWJ
Yoshiko Ishikawa        pH/total alkalinity                          MWJ
Ayaka Hatsuyama         pH/total alkalinity                          MWJ
Minoru Kamata           DIC                                          MWJ                
Yasuhiro Arii           DIC                                          MWJ
Tomoyuki Takamori       CTD/water sampling                           MWJ
Hiroshi Matsunaga       CTD/water sampling                           MWJ
Masayuki Fujisaki       CTD/water sampling                           MWJ
Shungo Oshitani         CTD/water sampling                           MWJ
Tatsuya Ando            Water sampling                               MWJ
Tomomi Watanabe         Water sampling                               MWJ
Kanako Yoshida          Water sampling                               MWJ
Mami Kawai              Water sampling                               MWJ
Hideki Yamamoto         Water sampling                               MWJ
Satoshi Okumura         Meteorology/geophysics/ADCP/XCTD             GODI
Kazuho Yoshida          Meteorology/geophysics/ADCP/XCTD             GODI
Harumi Ota              Meteorology/geophysics/ADCP/XCTD             GODI
Takuhei Shiozaki        Biology/water sampling                       UT
Satoshi Kitajima        Biology/water sampling                       UT
Taketoshi Kodama        Biology/water sampling                       UT
Hiroyuki Kurotori       Biology/water sampling                       UT
Sho Imai                CH4 and N2O/water sampling                   RGU
Chiho Kubota            CH4 and N2O/water sampling                   RGU
Wolfgang Schneider      CTD/water sampling                           COPAS
Camillia Pauline Garae  Observer                                     DGMWR
Harish Pratap           Observer                                     FMS
Sakae Toyoda            CH4 and N2O/water sampling                   TITECH
Taku Watanabe           CH4 and N2O/water sampling                   TITECH
__________________________________________________________________________________
    TITECH           Tokyo Institute of Technology



Table 1.5.1(d):  List of cruise participants for leg 3.
__________________________________________________________________________________

NAME                    RESPONSIBILITY                               AFFILIATION
----------------------  -------------------------------------------  -------------
Kenichi Sasaki          Chief scientist                              MIO/JAMSTEC
Fujio Kobayashi         Technician                                   MWJ
Sinsuke Toyoda          Technician                                   MWJ
Fuyuki Shibata          Technician                                   MWJ
Sinichiro Yokogawa      Technician                                   MWJ
Shoko Tatamisashi       Technician                                   MWJ
Hideki Yamamoto         Technician                                   MWJ
Nironori Sato           Technician                                   MWJ
Yasuhiro Arii           Technician                                   MWJ
Ryo Kimura              Meteorology/geophysics/ADCP/XCTD             GODI
Soichiro Sueyoshi       Meteorology/geophysics/ADCP/XCTD             GODI
Takuhei Shiozaki        Biology                                      UT
Satoshi Kitajima        Biology                                      UT
Taketoshi Kodama        Biology                                      UT
Hiroyuki Kurotori       Biology                                      UT
Taku Watanabe           CH4 and N2O                                  TITECH
Sho Imai                CH4 and N2O                                  RGU
Chiho Kubota            CH4 and N2O                                  RGU
Hiroshi Furutani        Air sampling                                 ORI
Jinyoung Jung           Air sampling                                 ORI
__________________________________________________________________________________
    ORI  Ocean Research Institute, The University of Tokyo




2   UNDERWAY OBSERVATION


2.1  NAVIGATION AND BATHYMETRY
     September 9, 2009


2.1.1  Navigation


(1) Personnel

    Shinya Okumura     (GODI) : Leg 1
    Satoshi Okumura    (GODI) : Leg 2
    Souichiro Sueyoshi (GODI) : Leg 3
    Ryo Kimura         (GODI) : Leg 1, Leg 3
    Yousuke Yuuki      (GODI) : Leg 1
    Kazuho Yoshida     (GODI) : Leg 2
    Harumi Ota         (GODI) : Leg2


(2) Overview of the equipment

Ship's position, speed and course were provided by Radio Navigation System on 
R/V MIRAI. The system integrates GPS position, Log speed, Gyro heading and 
other basic data on a workstation. Ship's course and speed over ground are 
calculated from GPS position. The workstation clock is synchronized to 
reference clock using NTP (Network Time Protocol). Navigation data, called 
"SOJ data", is distributed to client computer every second, and recorded 
every 60 seconds.

Navigation devices are listed below.

    1. GPS receiver (2sets): Trimble DS-4000 9-channel receiver, the antennas 
                             are located on Navigation deck, port and 
                             starboard side. GPS position from each receiver 
                             is converted to the position of radar mast.
    2. Doppler log:          Furuno DS-30, which use three acoustic beam for 
                             current measurement
    3. Gyrocompass:          Tokimec TG-6000, sperry mechanical gyrocompass
    4. Reference clock:      Symmetricom TymServ2lOO, GPS time server
    5. Workstation           Hewlett-Packard ZX2000 running HP-UX ver.11.22


(3) Data period  MR09-01 Leg 1: 17:58 UTC 09 Apr. 2009 to 23:59 UTC 19 May 2009 (UTC)
                 MR09-01 Leg 2: 00:00 UTC 21 May 2009 to 02:00 UTC 19 Jun. 2009 (UTC)


Figure 2.1.2: Cruise Track of MR09-01 Leg 2.
Figure 2.1.3: Cruise Track of MR09-01 Leg 3.



2.1.2  Bathymetry


(1) Personnel

    Takeshi Matsumoto  (University of the Ryukyus) : Principal investigator/Not on-board
    Masao Nakanishi    (Chiba University)          : Principal investigator/Not on-board
    Shinya Okumura     (GODI) : Leg1
    Satoshi Okumura    (GODI) : Leg2
    Souichiro Sueyoshi (GODI) : Leg3
    Ryo Kimura         (GODI) : Leg1, Leg3
    Yousuke Yuuki      (GODI) : Leg1
    Kazuho Yoshida     (GODI) : Leg2
    Harumi Ota         (GODI) : Leg2


(2) Overview of the equipments

R/V MIRAI equipped with a Multi Beam Echo Sounding system (MBES), SEABEAM 
2112.004 (SeaBeam Instruments Inc.) The main objective of MBES survey is 
collecting continuous bathymetry data along ship's track to make a 
contribution to geological and geophysical investigations and global 
datasets. Data interval along ship's track was max 17 seconds at 6,000 m. To 
get accurate sound velocity of water column for ray-path correction of 
acoustic multibeam, we used Surface Sound Velocimeter (SSV) data to get the 
sea surface (6.2 m depth) sound velocity, and the deeper depth profiles were 
calculated using temperature and salinity profiles from the nearest CTD data 
by the equation in Mackenzie (1981).

System configuration and performance of SEABEAM 2112.004,

    Frequency:             12 kHz
    Transmit beam width:   2 degree
    Transmit power:        20 kW
    Transmit pulse length: 3 to 20 msec.
    Depth range:           100 to 11,000 m
    Beam spacing:          1 degree athwart ship
    Swath width:           150 degree (max)
                           120 degree to 4,500 m
                           100 degree to 6,000 m
                           90 degree to 11,000 m
    Depth accuracy:        Within <0.5% of depth or ± 1 m, whichever is 
                           greater, over the entire swath. (Nadir beam has 
                           greater accuracy; typically within < 0.2% of depth 
                           or ± 1 m, whichever is greater)


(3) Data Period

    MR09-01 Legl: P21-029 on 14 April 2009 to P21-033 on 16 April 2009,
                  P21-014 on 17 April 2009 to P21-156 on 18 May 2009
    MR09-01 Leg2: P21-157 on 21 May 2009 to P21-288 on 19 June 2009
    MR09-01 Leg3: 20 June 2009 to 1 July 2009
                  (except for the territorial waters of Papua New Guinea)


(4) Data processing

     i. Sound velocity correction
        The continuous bathymetry data are split into small areas around each 
        CTD station. For each small area, the bathymetry data are corrected 
        using a sound velocity profile calculated from the CTD data in the 
        area. The equation of Mackenzie (1981) is used for calculating sound 
        velocity. The data processing is carried out using "mbbath" command 
        of MBsystem.

    ii. Editing and Gridding
        Gridding for the bathymetry data are carried out using the HIPS 
        software version 6.1 Service Pack 2 (CARIS, Canada). Firstly, the 
        bathymetry data during Ship's turning is basically removed before 
        "BASE surface" is made. A spike noise of each swath data is also 
        removed using "swath editor" and "subset editor". Then the bathymetry 
        data are gridded by "Interpolate" function of the software with 
        following parameters.

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

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


(5) Data Archive

Bathymetry data obtained during this cruise was submitted to the Data 
Integration and Analysis Group (DIAG) of JAMSTEC, and archived there.


(6) Tectonic history of the Pacific Plate

The Pacific Plate is the largest oceanic lithospheric plate on the Earth. The 
Pacific Plate was born around 190 Ma, Middle Jurassic (Nakanishi et al., 
1992). The tectonic history of the Pacific Plate has been exposed by many 
studies based on magnetic anomaly lineations. However, the tectonic history 
in some periods is still obscure because of lack of geophysical data. To 
reveal the entire tectonic history of the Pacific Plate from Middle Jurassic 
to the present, increase in geophysical data is indispensable.

Identification of magnetic anomaly lineations has been the most common method 
for tectonic studies of oceanic plates. After improvement of the multi-narrow 
beam echo sounder, we become able to describe lineated abyssal hills for the 
tectonic studies in detail. Abyssal hills are related to the nature of the 
mid-ocean ridges at which they form (e.g. Goff et al., 1997). For example, 
abyssal hills heights and widths tend to correlate inversely with spreading 
rates. Abyssal hills also change morphology depending on crustal thickness 
and magma supply, factors which can vary within a single ridge segment and/or 
can vary from one ridge segment to another. Abyssal hills are therefore an 
off-axis indicator of mid-ocean ridge spreading history.

We collected bathymetric data using SeaBeam 2112 during the cruise. Figures 
2.1.4 and 2.1.5 show examples of abyssal hills. Figure 2.1.4 is the 
bathymetric map near the East Pacific Rise (EPR). The crest of the EPR has 
about 2600 m depth and about 350 m higher than its foot. The depth of the 
seafloor near the edges of Figure 2.1.4a is about 3500 m. Most of the abyssal 
hills have the similar strike as the EPR, but some have different strikes 
from the EPR. The height of abyssal hills is 50 m near the EPR and is more 
than 200 m around 114°W.

Figure 2.1.5 is the bathymetric map of the seafloor south of the Manihiki 
Plateau and crosses the East Manihiki Scarp, which is a remarkably linear 
feature extending more than 700 km from the northeastern corner of the 
Manihiki plateau. Previous works (e.g., Viso et al., 2005; Downey et al., 
2007) show the existence of the abyssal hills with an E-W strike in this 
area. The abyssal hills originate from the Pacific-Phoenix Ridge in the 
mid-Cretaceous. The abyssal hills with an E-W strike exist west of 164°W 
(Figure 2.1.5b). The height of the abyssal hills is -100 m. Several knolls 
with depression exist around 165°15'W. The height of the knolls is about 600 
m. The abyssal hills east of the East Manihiki Scarp (EMS) have an NE-SW 
strike (Figure 2.1.5a, c). The height of abyssal hills is more than 100 m. 
The pattern of the abyssal hills near the EMS is similar to that around 2.5°S 
reported by Viso et al. (2005). They interpret these abyssal hills as 
intratransform spreading centers resulting from transtensional strain across 
the EMS. Thus, the abyssal hills east of the EMS in Figure 2.1.5(c) derive 
from the same mechanism.



REFERENCES

Downey, N.J., J.M. Stock, R.W. Clayton, and S.C. Cande (2007): History of the 
    Cretaceous Osbourn spreading center, J. Geophys. Res., 112, B04102, 
    doi:10.1029/2006JB004550.

Goff, J.A., Y. Ma, A. Shah, J.R. Cochran, and J.-C. Sempere (1997): 
    Stochastic analysis of seafloor morphology on the flank of the Southeast 
    Indian Ridge: The influence of ridge morphology on the formation of 
    abyssal hills, J. Geophys. Res., 102, 15,521-15,534.

Mackenzie, K.V. (1981): Nine-term equation for the sound speed in the oceans, 
    J. Acoust. Soc. Am., 70 (3), pp 807-812.

Nakanishi, M., K. Tamaki, and K. Kobayashi (1992): A new Mesozoic isochron 
    chart of the whole western Pacific Ocean: Paleomagnetic and tectonic 
    implications, Geophys. Res. Lett., 19, 693-696.

Searle, R. (1984): GLORIA survey of the East Pacific Rise Near 3.5°S: 
    Tectonic and volcanic characteristics of a fast spreading mid-ocean rise, 
    Tectonophysics, 101, 319-344.

Viso, R.F., R.L. Larson, and R.A. Pockalny (2005): Tectonic evolution of the 
    Pacific-Phoenix-Farallon triple junction in the South Pacific Ocean, 
    Earth Planet Sci. Lett., 233, 179-194.



Figure 2.1.4: Bathymetric Map around the East Pacific Rise. Contour interval 
              is 50 m. Bathymetry is illuminated from the northwest. Red 
              rectangles in (a) represent the areas of (b) and (c). Blue 
              dotted lines represent abyssal hills. A blue line shows the 
              crest of the East Pacific Rise.
Figure 2.1.5: Bathymetric Map of the seafloor south of the Manihiki Plateau. 
              Contour interval is 50 m. Bathymetry is illuminated from the 
              northwest. Red rectangles in (a) represent the areas of (b) and 
              (c). Yellow and blue dotted lines represent abyssal hills. EMS 
              represents the East Manihiki Scarp.




2.2  SURFACE METEOROLOGICAL OBSERVATION
     January 13, 2010


(1) Personnel

    Kunio Yoneyama     (JAMSTEC)
    Satoshi Okumura    (GODI)
    Souichiro Sueyoshi (GODI)
    Shinya Okumura     (GODI)
    Ryo Kimura         (GODI)
    Kazuho Yoshida     (GODI)
    Harumi Ota         (GODI)
    Yousuke Yuuki      (GODI)
    

(2) Objective

As a basic dataset that describes weather conditions during the cruise, 
surface meteorological observation was continuously conducted.


(3) Methods

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

Instruments of SMET are listed in Table 2.2.1. All SMET data were collected 
and processed by KOAC-7800 weather data processor made by Koshin Denki, 
Japan. Note that although SMET contains rain gauge, anemometer and 
radiometers in their system, we adopted those data from not SMET but SOAR due 
to the following reasons; 1) Since SMET rain gauge is located near the base 
of the mast, there is a possibility that its capture rate might be affected, 
2) SOAR's anemometer has better starting threshold wind speed (1 m s-1) 
comparing to SMET's anemometer (2 m-1), and 3) SMET's radiometers record data 
with 10 W/m2 resolution while SOAR takes high resolution data of 1 W/m2.

SOAR system was designed and constructed by the Brookhaven National 
Laboratory (BNL), USA, for an accurate measurement of solar radiation on the 
ship (cf. http://www.gim.bnl.gov/soarl). SOAR consist of 1) Portable 
Radiation Package (PRP) that measures short and long wave downwelling 
radiation, 2) Zen (meteorological system that measures pressure, air 
temperature, relative humidity, wind speed/direction and rainfall, and 3) 
Scientific Computer System (SCS) developed by the National Oceanic and 
Atmospheric Administration (NOAA), USA, for data collection, management, 
real-time monitoring, and so on. Information or sensors used here is listed 
in Table 2.2.2.


Table 2.2.1:  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    Sea-Bird Electronics, Inc.,  4th deck/-5 m
                                  USA/SBE3S*3  
Barometer      pressure           Setra Systems Inc., USA/370  captain deck/13 m
_____________________________________________________________________________________________
*1 Gill aspirated radiation shield 43408 made by R.M. Young, USA is attached.
*2 There are two thermometers at starboard and port sides.
*3 Sea surface temperature data were taken from EPCS surface water monitoring system.



Table 2.2.2:  Instruments and locations of SOAR.
________________________________________________________________________________________

SENSOR      PARAMETER              MANUFACTURER/TYPE      LOCATION/HEIGHT FROM SEA LEVEL
----------  ---------------------  ---------------------  ------------------------------
Anemometer  wind speed/direction   R.M. Young, USA/05106  foremast/25 m
Rain gauge  rainfall accumulation  R.M. Young, USA/50202  foremast/24 m
Radiometer  short wave radiation   Eppley, USA/PSP        foremast/24 m
            long wave radiation    Eppley, USA/PIR        foremast/24 m
________________________________________________________________________________________


(4) Data processing and data format

All raw data were recorded every 6 seconds. Datasets produced here are 
1-minute mean values (time stamp at the end of the average). These values are 
the simple mean of 8 samples, after removing maximum/minimum values from 10 
samples to exclude singular/erroneous data. Liner interpolation onto missing 
values was applied only when their interval is less than 5 minutes.

Since the thermometers are equipped on both starboard/port sides on the deck, 
we adopted air temperature/relative humidity data taken at upwind side. Dew 
point temperature was produced from relative humidity and air temperature 
data.

Any adjustment to a certain height was not applied except pressure data to 
the sea level.

Data are stored as ASCII format and contains following parameters. Time in 
UTC expressed as YYYYMMDDHHMM, time in Julian day (1.0000 = January 1, 
0000Z), longitude (°E), latitude (°N), pressure (hPa), air temperature (°C), 
dew point temperature (°C), relative humidity (%), sea surface temperature 
(°C), zonal wind component (m/sec), meridional wind component (m/sec), 
precipitation (mm/hr), downwelling shortwave radiation (W/m2), and downwelling 
longwave radiation (W/m2).

Missing values are expressed as "9999".


(5) Data Quality

To ensure the data quality, each sensor was calibrated as follows. Since 
there is a possibility for fine time resolution data sets to have some noises 
caused (generated) by turbulence, it is recommended to filter them out (ex. 
hourly mean) from this 1-minute mean data sets depending on the scientific 
purpose.

T/RH sensor:

Temperature and humidity probes were calibrated before/after the cruise by 
the manufacturer. Certificated accuracy of T/RH sensors are better than ± 
0.2°C and ± 2%, respectively.

We also checked T/RH values using another calibrated portable T/RH sensor 
(Vaisala, HIMP45A) before and after the cruise. The results are,

    Temperature (°C)
        Mean difference between T (SMET) and T (portable) is
            -0.08±0.17 (°C) at port side, -0.26±0.33 (°C) at starboard side.

    Relative Humidity (%)
        Mean difference between RH (SMET) and RH (portable) is
            1.3±0.5 (%) at port side, 1.3± 1.6 (%) at starboard side.

    Sea surface temperature sensor:
        Temperature sensor was calibrated before the cruise at the 
        manufacturer. Certificated accuracy is better than 0.002°C/year.

    Pressure sensor:
        Using calibrated portable barometer (Vaisala, Finland / PTB220, 
        certificated accuracy is better than ± 0.1 hPa), pressure sensor was 
        checked before/after the cruise. Mean difference of SMET pressure 
        sensor and portable sensor is 0.06±0.05 hPa.


Precipitation:

Before the each leg, we checked the linearity of rain gauge value in response 
to water amount in the gauge. The results are as follows, and data have 
already been corrected using this relationship.

          ________________________________________________________

                                            Leg-1   Leg-2   Leg-3
          -------------------------------   ------  ------  ------
          minimum input water volume (cc)     0.0     0.0     0.0
          maximum input water volume (cc)   505.0   505.7   503.7
          minimum measured value (mm)         0.47    0.25    0.47
          maximum measured value (mm)        50.23   48.75   49.79
          ________________________________________________________


    Radiation sensors:

        Short wave and long wave radiometers were calibrated by the 
        manufacturer, Remote Measurement and Research Company, USA, prior to 
        the cruise (February 2009).


(6) Data periods

    Leg-1  1300 UTC, April 10, 2009 - 0000 UTC, May 20, 2009
    Leg-2  0100 UTC, May 21,   2009 - 0100 UTC, June 19, 2009
    Leg-3  2300 UTC, June 19,  2009 - 2350 UTC, July 2, 2009


(7) Point of contact

    Kunio Yoneyama (yoneyamak@jamstec.go.jp)
    Research Institute for Global Change / JAMSTEC
    2-15, Natsushima, Yokosuka 237-0061, Japan


Figure 2.2.1: Time series of surface (a) air/sea temperature, (b) relative 
              humidity, (c) precipitation, (d) pressure, (e) zonal and 
              meridional wind components, and (e) short and long wave 
              radiation for Leg-1. Day 100 corresponds to April 10, 2009.
Figure 2.2.2: Same as Figure 2.2.1, but for Leg 2. Day 141 corresponds to May 
              21, 2009.
Figure 2.2.3: Same as Figure 2.2.1, but for Leg 3. Day 171 corresponds to 
              June 19, 2009.



2.3  THERMO-SALINOGRAPH AND RELATED MEASUREMENTS
     July 31, 2010


(1) Personnel

    Yuichiro Kumamoto (JAMSTEC)
    Miyo Ikeda        (MWJ)
    Fuyuki Shibata    (MWJ)
    Masanori Enoki    (MWJ)
    Misato Kuwahara   (MWJ)


(2) Objective

Our purpose is to obtain salinity, temperature, dissolved oxygen, and 
fluorescence data continuously in near-sea surface water during MR09-01 
cruise.


(3) Methods

The Continuous Sea Surface Water Monitoring System (Nippon Kaiyo Co. Ltd.), 
including the thermosalinograph, has five sensors and automatically measures 
salinity, temperature, dissolved oxygen, and fluorescence in near-sea surface 
water every one minute. This system is located in the sea surface monitoring 
laboratory and connected to shipboard LAN system. Measured data, time, and 
location of the ship were stored in a data management PC (IBM NetVista 
6826-CBJ). The near-surface water was continuously pumped up to the 
laboratory from about 4 m water depth and flowed into the system through a 
vinyl-chloride pipe. The flow rate of the surface seawater was adjusted to be 
12 dm3/min except for a fluorometer (about 0.4 dm3/min). Specifications of the 
each sensor in this system are listed below.

a) Temperature and salinity sensors
     SEACAT THERMOSALINOGRAPH
     Model:             SBE-21, SEA-BIRD ELECTRONICS, INC.
     Serial number:     2126391-3126
     Measurement range: Temperature -5 to +35°C (ITS-90), Salinity 0 to 7.0 5 m-1
     Accuracy:          Temperature 0.01°C 6month-1,      Salinity 0.001 5 m-1 month-1
     Resolution:        Temperatures 0.001°C,             Salinity0.0001 S a-1

b) Bottom of ship thermometer (RMT)
     Model:             SBE 3S, SEA-BIRD ELECTRONICS, INC.
     Serial number:     032175
     Measurement range: -5 to +35°C (ITS-90)
     Resolution:        ±0.001°C
     Stability:         0.002°C year-1

c) Dissolved oxygen sensor
     Model:             2127A, HACH ULTRA ANALYTICS JAPAN, INC.
     Serial number:     61230
     Measurement range: 0 to 14 ppm
     Accuracy:          ± 1% at 5°C of correction range
     Stability:         1% month-1

d) Fluorometer
     Model:             10-AU-005, TURNER DESIGNS
     Serial number:     5562 FRXX
     Detection limit:   5 ppt or less for chlorophyll-a
     Stability:         0.5% month-1 of full scale

e) Flow meter
     Model:             EMARG2W, Aichi Watch Electronics LTD.
     Serial number:     8672
     Measurement range: 0 to 30 1 min-1
     Accuracy:          ± 1%
     Stability:         ± 1% day-1


(4) Measurements

Periods of measurement, maintenance, and events during MR09-01 are listed in 
Table 2.3.1.


Table 2.3.1: Events list of the thermo-salinograph during MR09-01
_________________________________________________________________________

System Date  System Time
   [UTC]        [UTC]                  Events                  Remarks
-----------  -----------  --------------------------------  -------------
09-Apr.-14      12:47     All the measurements started.     Leg-1 start
09-Apr.-15      23:59     All the measurements stopped due 
09-Apr.-21      00:00     to entering in the Peruvian EEZ.  
09-Apr.-22      01:40     Lost of all the data due to re- 
09-Apr.-22      02:04     boot of the data management PC.  
09-May-18       07:06     All the measurements stopped.     Leg-1 finish
09-May-21       20:18     All the measurements started.     Leg-2a start
09-May-23       20:44     All the measurements stopped.     Leg-2a finish
09-May-25       20:19     All the measurements started.     Leg-2b start
09-Jun.-13      17:07     Lost of all the data due to   
                          error on program.
09-Jun.-13      17:18     Lost of all the data due to 
                          error on program.
09-Jun.-17      19:36     All the measurements stopped.     Leg-2b finish
09-Jun.-20      10:01     All the measurements started.     Leg-3 start
09-Jun.-23      22:59     Lost of all the data  
09-Jun.-24      14:03     Lost of all the data  
09-Jul.-01      04:23     All the measurements stopped.     Leg-3 finish
_________________________________________________________________________


(5) Calibrations

We collected the surface seawater samples for salinity sensor calibration 
during Leg-1 and Leg-2 (Table 2.3.2). The seawater was collected 
approximately twice a day using a 250 ml brown grass bottle. The samples were 
stored in the sea surface monitoring laboratory and then measured using the 
Guildline 8400B at the end of the legs after all the measurements of the 
hydrocast bottle samples.


Table 2.3.2:  Comparison of the sensor salinity with the bottle salinity.
_______________________________________________________________________________

                                               Sensor    Bottle
  Date     Time                               salinity  salinity   Difference
  [UTC]    [UTC]    Latitude      Longitude   [PSS-78]  [PSS-78]  [Sen. - Bot.]
---------  -----  ------------  ------------- --------  --------  -------------
2009/4/14  13:48  16-44.97580S  078-42.43970W  35.4984   35.4950     0.0034
2009/4/14  21:56  16-45.17830S  079-19.83920W  35.5812   35.5769     0.0043
2009/4/15  8:56   16-44.40370S  080-39.63650W  35.5748   35.5725     0.0023
2009/4/15  22:04  16-40.73990S  080-59.80990W  35.4099   35.4083     0.0016
2009/4/21  8:19   16-44.92050S  080-25.69800W  35.4962   35.4981    -0.0019
2009/4/21  21:10  16-44.52540S  082-00.27190W  35.5029   35.5088    -0.0059
2009/4/22  10:00  16-44.93300S  082-59.85970W  35.5844   35.5889    -0.0045
2009/4/22  10:02  16-44.91210S  082-59.85080W  35.5842   35.5890    -0.0048
2009/4/22  21:29  16-45.09040S  083-40.05760W  35.5448   35.5507    -0.0059
2009/4/23  8:51   16-44.56640S  084-20.09390W  35.6529   35.6570    -0.0041
2009/4/23  21:08  16-45.11350S  085-19.65940W  35.5000   35.5058    -0.0058
2009/4/24  9:52   16-49.99990S  086-23.16600W  35.7428   35.7466    -0.0038
2009/4/24  21:11  16-44.71580S  087-40.33490W  35.7371   35.7444    -0.0073
2009/4/25  10:36  16-45.00120S  088-39.82020W  35.7708   35.7750    -0.0042
2009/4/25  10:38  16-45.00260S  088-39.84800W  35.7718   35.7744    -0.0026
2009/4/25  20:55  16-44.78260S  089-20.05120W  35.7637   35.7691    -0.0054
2009/4/26  10:09  16-44.73750S  090-08.14720W  35.7523   35.7574    -0.0051
2009/4/26  21:41  16-44.78340S  091-28.27440W  35.7917   35.7951    -0.0034
2009/4/27  9:19   16-44.80660S  092-49.23870W  35.8304   35.8362    -0.0058
2009/4/27  21:37  16-43.85810S  094-21.16550W  35.8251   35.8318    -0.0067
2009/4/28  9:21   16-45.33650S  095-47.60370W  35.8719   35.8724    -0.0005
2009/4/28  9:23   16-45.34400S  095-48.13740W  35.8679   35.8707    -0.0028
2009/4/28  21:52  16-44.73560S  097-20.31890W  35.8107   35.8161    -0.0054
2009/4/29  9:38   16-44.79350S  098-40.12210W  35.9412   35.9454    -0.0042
2009/4/29  22:07  16-44.05720S  100-00.30900W  36.0435   36.0471    -0.0036
2009/4/30  10:07  16-44.61130S  101-28.24690W  35.9749   35.9805    -0.0056
2009/4/30  10:09  16-44.62880S  101-28.76720W  35.9771   35.9820    -0.0049
2009/4/30  21:57  16-59.19030S  102-58.24090W  35.9857   35.9880    -0.0023
2009/5/1   11:09  16-45.46850S  104-00.09040W  36.0785   36.0822    -0.0037
2009/5/1   23:39  16-45.03880S  106-00.04450W  36.0361   36.0432    -0.0071
2009/5/2   11:08  16-44.97480S  106-54.64000W  36.0931   36.0988    -0.0057
2009/5/3   1:48   16-45.49220S  107-15.05250W  36.1222   36.1272    -0.0050
2009/5/3   10:31  16-44.96970S  107-37.76710W  36.1409   36.1453    -0.0044
2009/5/3   23:03  16-45.14510S  109-19.99040W  36.1931   36.1985    -0.0054
2009/5/3   23:04  16-45.14910S  109-19.98920W  36.1924   36.1974    -0.0050
2009/5/4   11:33  16-45.13740S  110-40.38760W  36.2194   36.2242    -0.0048
2009/5/4   23:32  16-45.29100S  112-00.07440W  36.1544   36.1630    -0.0086
2009/5/5   10:47  16-45.25910S  113-37.45760W  36.3165   36.3205    -0.0040
2009/5/5   21:52  16-45.46490S  115-13.33820W  36.2483   36.2538    -0.0055
2009/5/6   11:27  16-44.98470S  116-42.80650W  36.3767   36.3807    -0.0040
2009/5/6   23:06  16-45.17100S  118-25.21730W  36.2563   36.2622    -0.0059
2009/5/7   11:36  16-45.09820S  120-00.16570W  36.2863   36.2924    -0.0061
2009/5/7   11:38  16-45.10700S  120-00.17050W  36.2868   36.2924    -0.0056
2009/5/8   7:21   16-45.09310S  122-39.65920W  36.2948   36.3001    -0.0053
2009/5/8   11:20  16-44.85160S  122-57.81300W  36.3801   36.3857    -0.0056
2009/5/8   23:17  16-45.11080S  124-39.69490W  36.4907   36.4951    -0.0044
2009/5/9   10:59  16-45.02640S  126-00.21060W  36.3923   36.3965    -0.0042
2009/5/9   23:45  16-45.30990S  127-20.52890W  36.3225   36.3272    -0.0047
2009/5/10  12:35  16-45.01200S  129-05.41100W  36.3609   36.3641    -0.0032
2009/5/10  12:37  16-45.01500S  129-05.91430W  36.3552   36.3591    -0.0039
2009/5/11  2:11   16-45.46310S  130-39.68820W  36.3718   36.3788    -0.0070
2009/5/11  12:12  16-45.05740S  131-59.97770W  36.4767   36.4823    -0.0056
2009/5/12  2:21   16-45.29710S  133-20.19320W  36.3381   36.3432    -0.0051
2009/5/12  11:51  16-45.56450S  134-00.34900W  36.2077   36.2137    -0.0060
2009/5/13  11:58  16-45.31040S  136-39.87070W  36.4252   36.4293    -0.0041
2009/5/13  12:00  16-45.30590S  136-39.85740W  36.4246   36.4307    -0.0061
2009/5/13  17:28  16-44.96630S  137-20.15810W  36.3616   36.3693    -0.0077
2009/5/14  0:08   16-45.09200S  138-22.38950W  36.3073   36.3105    -0.0032
2009/5/14  12:56  16-44.92430S  140-02.89960W  36.3949   36.4020    -0.0071
2009/5/15  0:27   16-44.56690S  141-43.14970W  36.2809   36.2862    -0.0053
2009/5/15  14:26  17-18.00390S  143-01.90900W  36.2908   36.2964    -0.0056
2009/5/16  0:40   17-29.56580S  144-09.39550W  36.3152   36.3204    -0.0052
2009/5/16  14:32  17-29.82400S  145-44.07210W  36.3189   36.3234    -0.0045
2009/5/16  14:34  17-29.85300S  145-44.45950W  36.3190   36.3243    -0.0053
2009/5/17  1:06   17-29.80410S  146-55.62150W  36.3267   36.3310    -0.0043
2009/5/17  12:53  17-30.21460S  148-28.58790W  36.2912   36.2957    -0.0045
2009/5/18  2:28   17-30.00190S  149-10.30590W  36.2251   36.2292    -0.0041
2009/5/18  7:03   17-29.95660S  149-19.96200W  36.2223   36.2345    -0.0122
2009/5/22  0:57   17-29.84320S  150-05.34030W  36.1993   36.1916     0.0077
2009/5/22  13:27  17-29.91300S  151-16.85460W  36.1192   36.1159     0.0033
2009/5/23  1:14   17-30.41760S  152-43.27130W  36.038    36.0309     0.0071
2009/5/23  13:20  17-30.39290S  154-03.86520W  35.9694   35.9629     0.0065
2009/5/23  19:06  17-30.73690S  154-19.15890W  35.9772   35.9698     0.0074
2009/5/26  0:33   17-30.27460S  150-56.34070W  36.148    36.1428     0.0052
2009/5/26  7:46   17-28.15840S  152-47.88450W  36.0207   36.0145     0.0062
2009/5/26  7:48   17-28.15860S  152-48.39390W  36.0187   36.0123     0.0064
2009/5/27  2:22   17-29.71150S  155-39.65110W  35.935    35.9279     0.0071
2009/5/27  12:43  17-30.14850S  156-59.98330W  35.9856   35.9789     0.0067
2009/5/28  2:43   17-30.05130S  158-21.80860W  35.6579   35.6521     0.0058
2009/5/28  13:17  17-29.60850S  159-40.16600W  35.7293   35.7217     0.0076
2009/5/29  3:15   17-29.62850S  161-00.53220W  35.7593   35.7527     0.0066
2009/5/29  12:44  17-29.84780S  162-20.19010W  35.5213   35.5153     0.0060
2009/5/29  12:46  17-29.84070S  162-20.19980W  35.5218   35.5148     0.0070
2009/5/30  0:51   17-29.71710S  163-40.22410W  35.5298   35.5240     0.0058
2009/5/30  13:14  17-29.86090S  165-00.09660W  35.658    35.6523     0.0057
2009/5/31  2:37   17-29.50610S  166-20.56290W  35.3233   35.3168     0.0065
2009/5/31  12:34  17-29.75890S  167-19.39840W  35.2629   35.2559     0.0070
2009/6/1   2:10   17-30.02270S  168-57.87450W  35.1326   35.1238     0.0088
2009/6/1   2:12   17-30.01870S  168-58.38400W  35.1286   35.1222     0.0064
2009/6/1   13:19  17-30.12720S  169-57.96900W  35.6192   35.6121     0.0071
2009/6/2   2:06   17-30.09560S  171-19.29490W  35.3532   35.3447     0.0085
2009/6/2   13:53  17-29.47620S  172-09.08020W  35.3759   35.3695     0.0064
2009/6/3   2:19   17-29.86830S  172-39.93180W  35.3979   35.3921     0.0058
2009/6/3   13:42  17-29.76370S  172-59.95610W  35.4848   35.4781     0.0067
2009/6/4   1:57   17-29.15390S  174-53.24790W  35.1388   35.1300     0.0088
2009/6/4   2:00   17-29.24690S  174-54.02150W  35.1391   35.1312     0.0079
2009/6/4   14:06  17-29.84240S  176-29.21680W  35.4266   35.4206     0.0060
2009/6/5   1:48   17-45.08660S  178-15.00220W  35.5201   35.5144     0.0057
2009/6/5   14:08  18-24.86800S  179-39.44760W  35.0543   35.0458     0.0085
2009/6/6   4:37   18-25.14400S  178-19.77450E  34.7175   34.7105     0.0070
2009/6/6   15:05  18-34.43890S  177-15.01060E  34.8111   34.8052     0.0059
2009/6/7   3:07   17-49.80500S  176-20.13720E  34.8422   34.8366     0.0056
2009/6/7   3:09   17-49.80020S  176-20.14540E  34.8446   34.8362     0.0084
2009/6/7   14:51  17-49.96720S  174-30.44490E  34.7476   34.7396     0.0080
2009/6/8   3:29   17-50.20620S  172-57.74250E  34.7886   34.7854     0.0032
2009/6/8   16:16  17-50.03360S  171-00.02810E  34.8332   34.8284     0.0048
2009/6/9   3:14   17-49.98500S  169-39.81200E  34.8549   34.8498     0.0051
2009/6/9   14:51  18-08.76050S  168-35.87720E  34.8734   34.8673     0.0061
2009/6/9   14:54  18-08.72630S  168-35.86890E  34.8733   34.8673     0.0060
2009/6/10  3:33   18-28.98480S  167-48.94890E  34.8825   34.8751     0.0074
2009/6/10  15:10  18-41.83330S  167-18.97920E  34.668    34.6618     0.0062
2009/6/11  4:30   19-09.22850S  166-15.30210E  34.6166   34.6111     0.0055
2009/6/11  15:48  19-35.14790S  165-13.44460E  34.8688   34.8621     0.0067
2009/6/12  4:20   19-55.09680S  164-26.87740E  34.7665   34.7596     0.0069
2009/6/12  4:23   19-55.03730S  164-27.09530E  34.7686   34.7604     0.0082
2009/6/12  14:15  18-41.18910S  163-27.76470E  34.7966   34.7912     0.0054
2009/6/13  5:09   20-52.28470S  164-12.34210E  34.9014   34.8964     0.0050
2009/6/13  15:40  20-58.30450S  164-05.86780E  35.1654   35.1531     0.0123
2009/6/14  4:12   21-28.99900S  162-45.98240E  34.894    34.8870     0.0070
2009/6/14  15:44  22-05.92740S  161-12.07260E  35.2426   35.2314     0.0112
2009/6/15  4:55   22-43.07240S  159-39.05030E  35.2074   35.1999     0.0075
2009/6/15  4:57   22-43.07120S  159-39.05450E  35.2077   35.2009     0.0068
2009/6/15  15:44  23-15.94420S  158-15.27150E  35.2435   35.2369     0.0066
2009/6/16  4:18   23-52.07610S  156-43.12080E  35.3243   35.3164     0.0079
2009/6/16  16:06  24-20.93430S  155-30.04440E  35.2284   35.2212     0.0072
2009/6/17  5:24   24-46.82500S  154-19.41980E  35.437    35.4248     0.0122
2009/6/17  18:53  25-02.01130S  153-38.93560E  35.3601   35.3536     0.0065
_______________________________________________________________________________



2.4  UNDERWAY pCO2
     December 4, 2010


(1) Personnel

Akihiko Murata   (RIGC, JAMSTEC)
Minoru Kamata    (MWJ)
Yoshiko Ishikawa (MWJ)
Yasuhiro Arii    (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 P21 revisit cruise, we were aimed at quantifying how much 
anthropogenic CO2 is absorbed in the surface ocean in the Pacific. For the 
purpose, we measured pCO2 (partial pressures of CO2) in the atmosphere and in 
the surface seawater.


(3) Apparatus and shipboard measurement

Continuous underway measurements of atmospheric and surface seawater pCO2 were 
made with the CO2 measuring system (Nippon ANS, Ltd) installed in the R/V 
Mirai of JAMSTEC. The system comprises of a non-dispersive infrared gas 
analyzer (NDIR; BINOS® model 4.1, Fisher-Rosemount), an air-circulation 
module and a showerhead-type equilibrator. To measure concentrations (mole 
fraction) of CO2 in dry air (xCO2a), air sampled from the bow of the ship 
(approx. 30 m above the sea level) was introduced into the NDIR through a 
dehydrating route with an electric dehumidifier (kept at -2°C), a Perma Pure 
dryer (GL Sciences Inc.), and a chemical desiccant (Mg(ClO4)2). The flow rate 
of the air was 500 ml min-1. To measure surface seawater concentrations of CO2 
in dry air (xCO2s), the air equilibrated with seawater within the equilibrator 
was introduced into the NDIR through the same flow route as the dehydrated 
air used in measuring xCO2a. The flow rate of the equilibrated air was 600 - 
800 ml min-1. The seawater was taken by a pump from the intake placed at the 
approx. 4.5 m below the sea surface. The flow rate of seawater in the 
equilibrator was 500 - 800 ml min-1.

The CO2 measuring system was set to repeat the measurement cycle such as 4 
kinds of CO2 standard gases (Table 2.4.1), xCO2a (twice), xCO2s (7 times). This 
measuring system was run automatically throughout the cruise by a PC control.


(4) Quality control

Concentrations of CO2 of the standard gases are listed in Table 2.4.1, which 
were calibrated by the JAMSTEC primary standard gases. The CO2 concentrations 
of the primary standard gases were calibrated by C.D. Keeling of the Scripps 
Institution of Oceanography, La Jolla, CA, USA.

Since differences of concentrations of the standard gases between before and 
after the cruise were allowable (<0.1 ppmv), the averaged concentrations 
(Table 2.4.1) were adopted for the subsequent calculations.

In actual shipboard observations, the signals of NDIR usually reveal a trend. 
The trends were adjusted linearly using the signals of the standard gases 
analyzed before and after the sample measurements.

Effects of water temperature increased between the inlet of surface seawater 
and the equilibrator on xCO2s were adjusted based on Gordon and Jones (1973), 
although the temperature increases were slight, being -0.3°C.

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



REFERENCE

Gordon, L.I. and L.B. Jones (1973) The effect of temperature on carbon 
    dioxide partial pressure in seawater. Mar. Chem., 1, 317-322.


Table 2.4.1:  Concentrations of CO2 standard gases used during MR09-01 cruise.
                      ___________________________________

                      Cylinder no.  Concentrations (ppmv)
                      ------------  ---------------------
                        CQC00742           270.22
                        CQC00739           330.43
                        CQC00740           360.04
                        CQC00741           420.32
                      ___________________________________



2.5  ACOUSTIC DOPPLER CURRENT PROFILER (ADCP)
     November 1, 2010


(1) Personnel

    Shinya Kouketsu    (JAMSTEC)
    Shinya Okumura     (GODI) -leg1-
    Ryo Kimura         (GODI) -leg1, 3-
    Yousuke Yuki       (GODI) -leg1-
    Satoshi Okumura    (GODI) -leg2-
    Kazuho Yoshida     (GODI) -leg2-
    Harumi Ohta        (GODI) -leg2-
    Souichiro Sueyoshi (GODI) -leg3-


(2) Objective

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


(3) Methods

Upper ocean current measurements were made throughout MR09-01 cruise, using 
the hull mounted Acoustic Doppler Current Profiler (ADCP) system. For most of 
its operation, the instrument was configured for water-tracking mode 
recording. Bottom-tracking mode, interleaved bottom-ping with water-ping, was 
made in shallower water region to get the calibration data for evaluating 
transducer misalignment angle.

The system consists of following components;

1) R/V MIRAI has installed the Ocean Surveyor for vessel-mount (acoustic 
   frequency 75 kHz; Teledyne RD Instruments). It has a phased-array 
   transducer with single ceramic assembly and creates 4 acoustic beams 
   electronically. We mounted the transducer head rotated to a ship-relative 
   angle of 45 degrees azimuth from the keel.

2) For heading source, we use ship's gyro compass (Tokimec, Japan), 
   continuously providing heading to the ADCP system directory. Additionally, 
   we have Inertial Navigation System (INS) which provide high-precision 
   heading, attitude information, pitch and roll, are stored in ".N2R" data 
   files with a time stamp.

3) GPS navigation receiver (Trimble D54000) provides position fixes.

4) We used VmDas version 1.4.2 (TRD Instruments) for data acquisition.

5) To synchronize time stamp of ping 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).

The data was configured for 4 m processing bin, 4 m intervals and starting 20 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. We changed the major 
parameters, and showed the date and time that we changed command file.


(4) Data processing

We processed ADCP data as described below. ADCP-coordinate velocities were 
converted to the earth-coordinate velocities using the ship heading from the 
INU. The earth-coordinate currents were obtained by subtracting ship 
velocities from the earth-coordinate velocities. Corrections of the 
misalignment and scale factors were made using the bottom track data. The 
misalignment angle calculated was 0.15, the scale factor was 1.00.


Figure 2.5.1.  Cruise-averaged echo intensities.


(5) Remarks

The profile with had quality is included between 200 m in depth and 400 m 
while in this cruise corresponding to weak echo intensities (Fig. 2.5.1 
causes of the weak echo intensity may be considered during data processing 
after cruise).



2.6  XCTD
     February 8, 2011


(1) Personnel

    Hiroshi Uchida (JAMSTEC)

      Leg 1
        Shinya Okumura  (GODI) 
        Ryo Kimura      (GODI) 
        Yosuke Yuki     (GODI) 

      Leg 2
        Satoshi Okumura (GODI) 
        Kazuho Yoshida  (GODI) 
        Harumi Ota      (GODI)


(2) Objectives

In this cruise, XCTD (expendable Conductivity, Temperature and Depth 
profiler) measurements were carried out to examine short-term changes in 
temperature and salinity profiles, and to evaluate fall rate equations by 
comparing with CTD (Conductivity, Temperature and Depth profiler) 
measurements and bottom topography measurements.


(3) Instrument and Method

The XCTDs used were XCTD-1 and XCTD-2 (Tsurumi-Seiki Co., Ltd., Yokohama, 
Kanagawa, Japan) with an MK-130 deck unit (Tsurumi-Seiki Co., Ltd.). The 
manufacturer's specifications are listed in Table 2.6.1. In this cruise, 
seven XCTD-1 probes and twenty-three XCTD-2 probes were deployed by using 
8-loading automatic launcher (Tsurumi-Seiki Co., Ltd.) (Table 2.6.2). Ship's 
speed was slowed down to 3 knot during the XCTD-2 measurement. For the 
comparison with CTD, XCTD was deployed at about 5 minutes for XCTD-1 and at 
about 10 minutes for XCTD-2 after the beginning of the down cast of the CTD.


Table 2.6.1:  Manufacturer's specifications of XCTD-1 and 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 - 1000 m (for XCTD-1)  5 m or 2%, whichever is greater *
                 0 - 1850 m (for XCTD-2)  5 m or 2%, whichever is greater *
  _________________________________________________________________________
  * Depth error is shown in Kizu et al (2008).


(4) Data Processing and Quality Control

The XCTD data were processed and quality controlled based on a method by 
Uchida et al. (2011). Thermal bias (+0.016°C) of the XCTD data reported by 
Uchida et al. (2011) was not corrected. Depth error of the XCTD data was 
corrected by using the estimated terminal velocity error (-0.0428 m s-1) 
(Uchida et al., 2011). 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 2.6.2). For the XCTD data of the 
station P21291, salinity bias could not be estimated because the maximum 
depth was too shallow to estimate the salinity bias.

Vertical section of potential temperature is shown in Fig. 2.6.1 for stations 
between 29 and 33. Comparison with the CTD data shows short-term fluctuation 
in temperature between the observation periods 6 days apart.



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 2.6.2: Serial number and probe type 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.

__________________________________________________________________________________

         Serial                                  Max     Salinity     Reference
         number         Depth   SST     SSS    pressure   offset      salinity
Station  (type)          [m]    [°C]   [PSU]    [dbar]    [PSU]        [PSU]
-------  -------------  -----  ------  ------  --------  --------  ---------------
Leg 1
29_1*    08112315 (2)   3798   23.759  35.444    187‡        -            NA
29_2*    08112312 (2)   3816   23.725  35.430    1967      0.009   34.6215 @ 2.5°C
30_1*    08112308 (2)   4462   24.249  35.432    1967      0.021   34.6215 @ 2.5°C
31_1*    08112304 (2)   4441   24.815  35.497    1913      0.022   34.6215 @ 2.5°C
32_1*    08112309 (2)   4713   23.453  35.480    1917      0.007   34.6215 @ 2.5°C
33_1*    08112306 (2)   4442   23.787  35.538    1967      0.014   34.6215 @ 2.5°C
41_1     03022164 (1)   4659   23.975  35.456    1036      0.023   34.5219 @ 4.5°C
41_2     08112305 (2)   4659   23.977  35.455    1967      0.007   34.6215 @ 2.5°C
34_1     08112307 (2)   4536   24.030  35.505    1967      0.012   34.6215 @ 2.5°C
34_2     07022711 (1)#  4537   24.029  35.505    1037      0.000   34.5219 @ 4.5°C
42_1     03022159 (1)   4558   23.544  35.584    1037     -0.017   34.5219 @ 4.5°C
42_2     08112310 (2)   4572   23.547  35.585    1967      0.015   34.6215 @ 2.5°C
96_1     03022156 (l)   3732   25.612  36.217    1036     ?0.005   34.5219 @ 4.5°C
96_2     08112311 (2)   3751   25.610  36.218    1967      0.007   34.6215 @ 2.5°C
97_1     03022162 (l)   3462   25.592  36.166    1037      0.012   34.5219 @ 4.5°C
97_2     08112313 (2)   3453   25.591  36.166    1967      0.010   34.6215 @ 2.5°C
98_1     03022157 (l)   3287   25.649  36.149    1037      0.002   34.5219 @ 4.5°C
98_2     08112314 (2)   3297   25.659  36.162    1967      0.010   34.6215 @ 2.5°C
145_1    08112319 (2)   1505   28.117  36.244    1464      0.007   34.5665 @ 3.0°C
146_1    08112316 (2)   1530   27.918  36.291    1520      0.020   34.5665 @ 3.0°C
151_1    08112322 (2)   1531   28.009  36.315    1518      0.005   34.5665 @ 3.0°C
156_1    03022155 (l)   943    28.339  36.223    943       0.008   34.4726 @ 4.5°C
Leg 2 
205_1    08112325 (2)   1365   28.097  35.430    1356      0.014   34.4781 @ 3.5°C
206_1    08112317 (2)   1484   27.978  35.548    1470      0.037   34.5512 @ 3.0°C
209_1    08112318 (2)   1924   27.032  35.260    1286‡     0.008   34.4911 @ 3.5°C
213_1    08112327 (2)   991    26.979  35.232    985       0.016   34.4238 @ 4.5°C
221_1    08112320 (2)   1883   26.466  34.783    1911     -0.004   34.6094 @ 2.5°C
250_1    08112321 (2)   1716   25.045  34.938    1700      0.013   34.5710 @ 3.0°C
266_1    08112324 (2)   1638   24.094  34.950    1631     -0.001   34.5860 @ 3.0°C
268_1    08112323 (2)   1562   23.496  35.227    1551      0.014   34.5860 @ 3.0°C
__________________________________________________________________________________
* Not for simultaneous measurements with CTD
‡ Failure of measurements due to noise or lost contact
# Relatively large (about 30 minutes) time difference between CTD and XCTD measurements



Figure 2.6.1: Vertical sections of potential temperature measured by CTD 
              (left) and XCTD (right).





3   Hydrographic Measurement Techniques and Calibrations

3.1  CTDO2 MEASUREMENTS
     February 16, 2010


(1) Personnel

    Hiroshi Uchida      (JAMSTEC)
    Wolfgang Schneider  (University of Concepcion, Chile)

    Leg 1 and leg 2a
      Kenichi Katayama  (MWJ)
      Shinsuke Toyoda   (MWJ)
      Hirokatsu Uno     (MWJ)
      Hiroyuki Hayashi  (MWJ)

    Leg 2b
      Tomoyuki Takamori (MWJ)
      Hiroshi Matsunaga (MWJ)
      Masayuki Fujisaki (MWJ)
      Shungo Oshitani   (MWJ)
      Satoshi Ozawa     (MWJ)


(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), three oxygen optodes (Oxygen Optode 3830 and 
4330F; Aanderaa Data Instruments AS, Bergen, Norway, and a prototype of 
RINKO-III; JFE Alec Co., Ltd, Kobe Hyogo, Japan), a fluorometer (Seapoint 
sensors, Inc., Kingston, New Hampshire, USA), and a transmissometer (C-Star 
Transmissometer; WET Labs, Inc., Philomath, Oregon, USA) 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).


SUMMARY OF THE SYSTEM USED IN THIS CRUISE 

Deck unit:
    SBE 11plus, S/N 0272 

Under water unit:
    SBE 9plus, S/N 79511 (Pressure sensor: S/N 0677)

Temperature sensor:
    SBE 3plus, S/N 4815 (primary)
    SBE 3, S/N 1525 (secondary)

Conductivity sensor:
    SBE 4, S/N 2854 (primary)
    SBE 4, S/N 1203 (secondary: stations from P21_14_1 to P21_86_1)
    SBE 4, S/N 3261 (secondary: stations from P21_87_1 to P21_288_1)

Oxygen sensor:
    SBE 43, S/N 0394 (stations from P21_14_1 to P21_76_1)
    SBE 43, S/N 0330 (stations from P21_X18_1 to P21_288_1)
    AANDERAA Oxygen Optode 3830, S/N 612 (foil batch no. 1707)
    AANDERAA Oxygen Optode 4330E S/N 143 (foil batch no. 2808F)
    JFE Alec RINKO-III, S/N 006 (foil batch no. 131002A)

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

Altimeter:
    PSA-916T, S/N 1100

Deep Ocean Standards Thermometer:
    SBE 35, S/N 0045

Fluorometer:
    Seapoint Sensors, Inc., S/N 3054

Transmissometer:
    C-Star, S/N CST-207RD

Carousel Water Sampler:
    SBE 32, S/N 0391

Water sample bottle:
    12-litre Niskin-X model 1010X (no TEFLON coating)

* without Oxygen Optode 4330E fluorometer, and transmissometer at 
  station P21_200_1



(4) Pre-cruise calibration

i.  Pressure

The Paroscientific series 4000 Digiquartz high pressure transducer (Model 
415K-187: Paroscientific, Inc., Redmond, Washington, USA) uses a quartz 
crystal resonator whose frequency of oscillation varies with pressure induced 
stress with 0.01 per million of resolution over the absolute pressure range 
of 0 to 15000 psia (0 to 10332 dbar). Also, a quartz crystal temperature 
signal is used to compensate for a wide range of temperature changes at the 
time of an observation. The pressure sensor has a nominal accuracy of 0.015% 
FS (1.5 dbar), typical stability of 0.0015% FS/month (0.15 dbar/month), and 
resolution of 0.001% FS (0.1 dbar). Since the pressure sensor measures the 
absolute value, it inherently includes atmospheric pressure (about 14.7 psi). 
SEASOFT subtracts 14.7 psi from computed pressure automatically.

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

    S/N 0677, 4 May 2007

The time drift of the pressure sensor is adjusted by periodic recertification 
corrections against a dead-weight piston gauge (Model 480DA, S/N 23906; 
Bundenberg Gauge Co. Ltd., Irlam, Manchester, UK). The corrections are 
performed at JAMSTEC, Yokosuka, Kanagawa, Japan by Marine Works Japan Ltd. 
(MWJ), Yokohama, Kanagawa, Japan, usually once in a year in order to monitor 
sensor time drift and linearity.

    S/N 0677, 9 December 2008 
        slope = 0.99977580 
        offset = -0.02383

Result of the pre-cruise pressure sensor calibration against the dead-weight 
piston gauge is shown in Fig. 3.1.1.


Figure 3.1.1:	Difference between the dead-weight piston gauge and the CTD 
              pressure. The calibration line (black line) is also shown.


ii.   Temperature (SBE 3)

The temperature sensing element is a glass-coated thermistor bead in a 
stainless steel tube, providing a pressure-free measurement at depths up to 
10500 (6800) m by titanium (aluminum) housing. The SBE 3 thermometer has a 
nominal accuracy of 1 mK, typical stability of 0.2 mK/month, and resolution 
of 0.2 mK at 24 samples per second. The premium temperature sensor, SBE 
3plus, is a more rigorously tested and calibrated version of standard 
temperature sensor (SBE 3).

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

    S/N 4815, 26 November 2008 
    S/N 1525, 25 November 2008

Pressure sensitivity of SBE 3 was corrected according to a method by Uchida 
et al. (2007), for the following sensor. 

    S/N 4815, -3.45974716e-7 [°C/dbar] 
    S/N 1525,  5.92243e-9 [°C/dbar]

Time drift of the SBE 3 temperature sensors based on the laboratory 
calibrations is shown in Fig. 3.1.2.



Figure 3.1.2: Time drift of SBE 3 temperature sensors based on laboratory 
              calibrations.


iii.   Conductivity (SBE 4)

The flow-through conductivity sensing element is a glass tube (cell) with 
three platinum electrodes to provide in-situ measurements at depths up to 
10500 (6800) m by titanium (aluminum) housing. The SBE 4 has a nominal 
accuracy of 0.0003 S/m, typical stability of 0.0003 S/m/month, and resolution 
of 0.00004 S/m at 24 samples per second.

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

    S/N 2954, 25 November 2008 (new cell preventing a stress concentration) 
    S/N 1203, 12 December 2008 (new cell preventing a stress concentration)
    S/N 3261, 17 December 2008 (new cell preventing a stress concentration)

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 in. The range for dissolved oxygen 
is 120% of surface saturation in all natural waters, nominal accuracy is 2% 
of saturation, and typical stability is 2% per 1000 hours.

Pre-cruise sensor calibrations were performed at SBE, Inc. S/N 0394, 20 
December 2008 S/N 0330, 20 December 2008


v.   Deep Ocean Standards Thermometer

Deep Ocean Standards Thermometer (SBE 35) is an accurate, ocean-range 
temperature sensor that can be standardized against Triple Point of Water and 
Gallium Melt Point cells and is also capable of measuring temperature in the 
ocean to depths of 6800 m. The SBE 35 was used to calibrate the SBE 3 
temperature sensors in situ (Uchida et al., 2007).

Pre-cruise sensor linearization was performed at SBE, Inc. 

    S/N 0045, 27 October 2002

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

    S/N 0045, 23 December 2008 (slope and offset correction)

The time required per sample = 1.1 x NCYCLES + 2.7 seconds. The 1.1 seconds 
is total time per an acquisition cycle. NCYCLES is the number of acquisition 
cycles per sample and was set to 4. The 2.7 seconds is required for 
converting the measured values to temperature and storing average in EEPROM.

When using the SBE 911 system with SBE 35, the deck unit receives incorrect 
signal from the under water unit for confirmation of firing bottle #16. In 
order to correct the signal, a module (Yoshi Ver. 1; EMS Co. Ltd., Kobe, 
Hyogo, Japan) was used between the under water unit and the deck unit.

Time drift of the SBE 35 based on the fixed point calibrations is shown in 
Fig. 3.1.3.


Figure 3.1.3: SBE35 time drift based on laboratory fixed point calibrations 
              (triple point of water, TPW and gallium melt point, GaMP) 
              performed by SBE, Inc.


vi. Altimeter

Benthos PSA-916T Sonar Altimeter (Teledyne Benthos, Inc.) determines the 
distance of the target from the unit by generating a narrow beam acoustic 
pulse and measuring the travel time for the pulse to bounce back from the 
target surface. It is rated for operation in water depths up to 10000 m. The 
PSA-916T uses the nominal speed of sound of 1500 m/s.

vii. Oxygen Optode

(a) Oxygen Optode 3830

Oxygen Optode 3830 (Aanderaa Data Instruments AS) is based on the ability of 
selected substances to act as dynamic fluorescence quenchers. In order to use 
with the SBE 911plus CTD system, an analog adaptor (3966) is connected to the 
oxygen optode (3830). The analog adaptor is packed into titanium housing made 
by Alec Electronics Co., Ltd. The sensor is designed to operate down to 6000 
m. The range for dissolved oxygen is 120% of surface saturation in all 
natural waters, nominal accuracy is less than 8 µM or 5% of saturation which 
ever is greater and setting time (63%) is shorter than 25 seconds.

(b) Oxygen Optode 4330F

Oxygen Optode 4330F (Aanderaa Data Instruments AS) is based on the ability of 
selected substances to act as dynamic fluorescence quenchers. In order to use 
with the SBE 911plus CTD system, an analog adaptor (3966) with titanium 
housing for Oxygen Optode 3975 is connected to the oxygen optode (4330F). The 
sensor is designed to operate down to 6000 m. The range for dissolved oxygen 
is 150% of surface saturation in all natural waters, nominal accuracy is less 
than 8 µM or 5% of saturation which ever is greater and setting time (63%) is 
shorter than 8 seconds.

(c) 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 Optode 3830 and RINKO are the raw phase shift data. Raw phase 
shift data for Optode 4330F can be back calculated from the outputs (oxygen 
concentration and temperature). The optode oxygen can be calibrated by the 
Stern-Volmer equation, according to a method by Uchida et al. (2008) with 
slight modification:

    O2 (µmol/l) = [(V0 / V)2 - 1] / KSV 

where V is voltage, V0 is voltage in the absence of oxygen and KSV is 
Stern-Volmer constant. The VO 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 temperature data from the first responding 
CTD temperature sensor instead of temperature data from slow responding 
optode temperature sensor. 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 salinity-compensated oxygen 
can be calculated by multiplying the factor of the effect of salt on the 
oxygen solubility (Garcia and Gordon, 1992). Garcia and Gordon (1992) have 
recommended the use of the solubility coefficients derived from the data of 
Benson and Krause.

The calibration coefficients were preliminary determined by using the bottle 
oxygen data obtained in this cruise, and used during the cruise.

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.


(5) Data collection and processing

i. Data collection

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

The package was lowered into the water from the starboard side and held 10 m 
beneath the surface 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 (20 seconds from station P21_23_1) and the package was stayed 
at least 5 seconds for measurement of the SBE 35. At 200 m (or 300 m) from 
the surface, the package was stopped to stop the heave compensator of the 
crane.

Water samples were collected using a 36-bottle SBE 32 Carousel Water Sampler 
with 12-litre Niskin-X bottles. Before a cast taken water for CFCs, the 
36-bottle frame and Niskin-X bottles were wiped with acetone.


Data acquisition software
    SEASAVE-Win32, version 7.18c


ii. Data collection problems

(a) Temperature and conductivity sensors

Since differences of temperature-salinity relationship calculated from the 
secondary sensors between downcast and upcast were larger than that 
calculated from the primary sensors, the secondary conductivity sensor S/N 
1203 was replaced with the conductivity sensor S/N 3261 after the station 
P21_86_1. However, the differences were still larger than that calculated 
from the primary sensors. The results suggest that the secondary temperature 
sensor S/N 1525 may have a pressure hysteresis relatively larger than the 
primary temperature sensor.

At the station P21161, the primary temperature and conductivity data were 
noisy probably due to jellyfish in the primary TC duct. Therefore, the second 
cast P21_16_2 was carried out.

At the station P21261, the primary temperature and conductivity data were 
noisy probably due to jellyfish in the primary TC duct. Since the second cast 
was not carried out, the secondary temperature and conductivity data must be 
used for this station.

(b) SBE43 oxygen sensor

Since differences between downcast and upcast profiles near the surface 
gradually became large, the SBE43 oxygen sensor S/N 0394 was replaced with 
the oxygen sensor S/N 0330 after the station P21_76_1.

(c) Miss trip and miss fire

Niskin bottles did not trip correctly at the following stations.

                         Miss trip    Miss fire
                        -----------  ------------
                        P21331, #13  P21611,  #14
                        P21181, #13  P21691,  #15
                        P21361, #15  P211771, #21
                                     P211851, #21
                                     P211881, #21
                                     P212551, #33


(d) Problem of the Niskin bottle #13

Discrepancies between CTD salinity and bottle sampled salinity data for the 
bottle #13 (about 3000 dbar) were slightly larger (about 0.001) than that 
obtained from neighboring bottles during leg 1. Bottle salinity data were 
obtained from a different bottle at the same depth of following stations, and 
were compared with the bottle salinity data obtained from the bottle #13.

    Bottle #2 of P21471
    Bottle #3 of P211311, P211321, P211331, P211351, P211371 
    Bottle #9 of P211361

Mean difference with standard error between CTD salinity and bottle salinity 
data are -0.0021 ± 0.0002 and -0.0013 ± 0.0001 for the bottle #13 and for the 
duplicate bottles, respectively. Salinity data from bottle #13 were 
significantly smaller than the other bottles probably due to slight leakage, 
although leak was not found for the bottle #13 at the water sampling. 
Therefore, the Niskin bottle #13 (S/N X12013) was replaced with the Niskin 
bottle S/N X12014 after the station P21_141_1, and the bottle flags of #13 
for stations from P21_29_1 to P21_141_1 were set to 7 (unknown problem). For 
the other water sampling parameters, significant difference was not detected 
for the duplicate bottle comparison (#2 and #13) at the station P21471.

(e) Errors of bottle sampled oxygen data from nitrites

During the determination of dissolved oxygen by using the Winkler method, 
errors from nitrites were introduced at the time the solution was made acidic 
with sulfuric acid (Wetzel and Gene, 2000). Therefore, the bottle sampled 
oxygen data were corrected when the nitrite concentration was high (> 0.5 
µmol/kg) as follows and used for the CTD oxygen calibration.

    O2c, = O2- 0.25 NO2

If the nitrite concentration was higher than 5 µmol/kg, the bottle sampled 
oxygen data was not used, because the error was significantly greater than 
0.25 NO2.

(f) Other incidents of note

At the station P21_200_1, Oxygen Optode 4330F, fluorometer, and 
transmissometer were removed from the CTD system, because the maximum 
pressure (6500 dbar) for the cast was beyond the proof pressure of these 
sensors (6000 m).

To gain more observation time, the bottle was fired after waiting from the 
stop for 20 seconds at each bottle firing stops from station P21_23_1. 
Immediately after the bottle firing stop, water around the instruments can be 
contaminated by the wake effect (Uchida et al., 2007). Although the wake 
effect is usually large within the first 20 seconds of the stop, the data may 
somewhat contaminated by the wake effect.

At the station P21_97_1, the cast was aborted at 285 dbar of the down cast 
due to a bad condition of the winch system, and the second cast P21_97_2 was 
carried out. At the station P21_118_1, the cast was aborted at 54 dbar of the 
down cast due to a mistake of the parameter setting for the LADCP, and the 
second cast P21_118_2 was carried out.

iii. Data processing

SEASOFT consists of modular menu driven routines for acquisition, display, 
processing, and archiving of oceanographic data acquired with SBE equipment. 
Raw data are acquired from instruments and are stored as unmodified data. The 
conversion module DATCNV uses instrument configuration and calibration 
coefficients to create a converted engineering unit data file that is 
operated on by all SEASOFT post processing modules. The following are the 
SEASOFT and original software data processing module sequence and 
specifications used in the reduction of CTD data in this cruise.


Data acquisition software
    SEASOFT-Win32, version 7.18c

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. 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.

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 5 seconds advancing 
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.

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, Optode 
3830, 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.

OPTBACKCAL (original module, version 1.0) calculated raw phase shift data of 
the Optode 4330F from the Optode 4330F outputs (oxygen concentration and 
temperature data). For bottle information data, this module was applied 
before applying the module BOTTLESUM.

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. 
The atmospheric pressure was measured at the captain deck (20 m high from the 
base line) and sub-sampled one-minute interval as a meteorological data. Time 
series of the CTD deck pressure is shown in Fig. 3.1.4.

The CTD pressure sensor offset was estimated from the deck pressure obtained 
above. Mean of the pre- and the post-casts data over the whole period gave an 
estimation of the pressure sensor offset from the pre-cruise calibration. 
Mean residual pressure between the dead-weight piston gauge and the 
calibrated CTD data at 0 dbar of the pre-cruise calibration was subtracted 
from the mean deck pressure. Estimated mean offset of the pressure data is 
listed in Table 3.1.1. The post-cruise correction of the pressure data is not 
deemed necessary for the pressure sensor.


Figure 3.1.4: Time series of the CTD deck pressure. Black dot indicates 
              atmospheric pressure anomaly. Blue and green dots indicate pre- 
              and post-cast deck pressures, respectively. Red dot indicates 
              an average of the pre- and the post-cast deck pressures.


Table 3.1.1: Offset of the pressure data. Mean and standard deviation are 
             calculated from time series of the average of the pre- and the 
             post-cast deck pressures.
         _________________________________________________________

                         Mean deck  Standard   Residual  Estimated 
                 Number   pressure  deviation  pressure   offset
                of cast    [dbar]    [dbar]     [dbar]    [dbar]
         -----  -------  ---------  ---------  --------  ---------
         Leg 1          
                  140       0.02      0.03       0.13      -0.11
         Leg 2                            
                  117       0.02      0.02       0.13      -0.11
         _________________________________________________________


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.
  SIN 0045, 19 August 2009 (2nd step: fixed point calibration)
     Slope =   1.000013
     Offset = -0.001173

Offset of the SBE 35 data from the pre-calibration was estimated to be 
smaller than 0.1 mK for temperature smaller than 4.5C. So the post-cruise 
correction of the SBE 35 temperature data was not deemed necessary for the 
SBE 35.

The CTD temperature was preliminary 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 1950 dbar.

The primary temperature data were basically used for the post-cruise 
calibration. The secondary temperature sensor was also calibrated and used 
instead of the primary temperature data for the station P21_26_1. The number 
of data used for the calibration and the mean absolute deviation from the SBE 
35 are listed in Table 3.1.2 and the calibration coefficients are listed in 
Table 3.1.3. The results of the post-cruise calibration for the CTD 
temperature are summarized in Table 3.1.4 and shown in Figs. 3.1.6 and 3.1.7.


Table 3.1.2: Number of data used for the calibration (pressure ≥ 1950 dbar) 
             and mean absolute deviation between the CTD temperature and the 
             SBE 35.
   _________________________________________________________________________

   Leg  Serial number  Number  Mean absolute deviation  Note
   ---  -------------  ------  -----------------------  --------------------
    1       4815        1315           0.l mK           
    1       1525        1315           0.1 mK           for station P21_26_1
    2       4815         834           0.1 mK           
    2       1525         834           0.1 mK           Not used
   _________________________________________________________________________


Table 3.1.3: Calibration coefficients for the CTD temperature sensors.
             ______________________________________________________

             Leg  Serial number  c0 (°C/dbar)  c1 (°C/day)  c2 (°C)
             ---  -------------  ------------  -----------  -------
              1       4815        1.03996e-8   2.23793e-6   -0.0000
              1       1525       -7.61078e-9   1.76847e-6    0.0005
              2       4815       -4.16502e-8   3.67354e-7   -0.0003
              2       1525        1.76844e-8  -1.01065e-5    0.0024
             ______________________________________________________


Table 3.1.4: Difference between the CTD temperature and the SBE 35 after the 
             post-cruise calibration. Mean and standard deviation (Sdev) are 
             calculated for the data below and above 1950 dbar Number of data 
             used is also shown.
             _____________________________________________________

                     Pressure ≥ 1950 dbar    Pressure < 1950 dbar
                     --------------------    ---------------------
             Serial          Mean   Sdev                Mean  Sdev
             number  Number  (mK)   (mK)     Number     (mK)  (mK) 
             ------  ------  -----  ----     ------     ----  ----
             Leg 1          
               4815   1315   -0.01   0.2      2647      -0.03  8.7
               1525   1315   -0.01   0.2      2647       0.46  9.8
             Leg 2                       
               4815    834   -0.00   0.3      2171      -0.42  4.8
               1525    834   -0.02   0.5      2171      -0.00  5.2
             _____________________________________________________


Figure 3.1.5: Difference between the CTD temperature 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. Results from 
              the primary temperature sensor (S/N 4815) are shown.
Figure 3.1.6: Same as Fig. 3.1.5, but for the secondary temperature sensor 
              (S/N 1525).


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 14 April 2009 and c0, c1, c2, c3 and c are calibration coefficients. The 
best fit sets of coefficients were determined by a weighted least square 
technique to minimize the deviation from the conductivity calculated from the 
bottle salinity data. The revised quasi-Newton method (FORTRAN subroutine 
DMINF1 from the Scientific Subroutine Library II, Fujitsu Ltd., Kanagawa, 
Japan) was used to determine the sets. The weight was given as a function of 
pressure as

    Weight = min100, exp{log(100) x P / PR}]

where PR is threshold of the pressure (950 dbar). When pressure is large 
(small), the weight is large (small) at maximum (minimum) value of 100 (1).

The primary conductivity data created by the software module ROSSUM were 
basically used after the post-cruise calibration for the temperature data. 
For the station P21_26_1, the secondary conductivity data was used, because 
the primary conductivity data was not able to be used for the station. Data 
from the station P21_14_1 to P21_27_1 were used for the calibration of the 
secondary conductivity. The coefficients were determined for each leg. The 
calibration coefficients are listed in Table 3.1.5. The results of the 
post-cruise calibration for the CTD salinity are summarized in Table 3.1.6 
and shown in Fig. 3.1.7.


Table 3.1.5: Calibration coefficients for the CTD conductivity sensors.
_____________________________________________________________________________________

Number    c0      c1 [S/(m dbar)]  c2 (1/dbar)  c3 [S/(m day)]    c4 (S/m)     Note
------  --------  ---------------  -----------  --------------  -----------  --------
Leg 1            
  3743  1.00015      3.00883e-8    -9.60863e-8    4.24710e-6    -4.86614e-4  S/N 2854
   330  0.999985     1.87529e-7    -6.74291e-8    5.33449e-5    -9.41355e-5  S/N 1203
Leg 2                    
  2849  1.00021     -3.50016e-8     5.62948e-9   -1.22961e-6    -4.63040e-4  S/N 2854
_____________________________________________________________________________________


Table 3.1.6: Difference between the CTD salinity and the bottle salinity 
             after the post-cruise calibration. Mean and standard deviation 
             (Sdev) (in 10) are calculated for the data below and above 950 
             dbar. Number of data used is also shown.
          ____________________________________________________________

                            Pressure ≥ 950 dbar    Pressure < 950 dbar
                            -------------------    -------------------
         Leg (Serial no.)   Number   Mean  Sdev    Number  Mean  Sdev
         ----------------   ------  -----  ----    ------  ----  ----
           Leg 1 (2854)      1933   -0.02  0.42     1810   0.15  5.57
           Leg 1 (1203)       163   -0.00  0.40      167   0.13  3.20
           Leg 2 (2854)      1347    0.00  0.39     1502   0.05  4.58
          ____________________________________________________________


Figure 3.1.7: Difference between the CTD salinity 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. Results from the primary 
              conductivity sensor (S/N 2854) are shown.
  

iv. Oxygen

The RINKO oxygen optode was calibrated and used as the CTD oxygen data, since 
the RINKO has a fast time response. However, the time-dependent, 
pressure-induced effect on the sensing foil was large for the RINKO, as was 
observed for the SBE 43. Data from the RINKO was corrected for the 
time-dependent, pressure-induced effect by means of the same method as that 
developed for the SBE 43 (Sea-Bird Electronics, 2009). The calibration 
coefficients, H1 (amplitude of hysteresis correction), H2 (curvature function 
for hysteresis), and H3 (time constant for hysteresis) were determined 
empirically as:

H1 = 0.0065
H2 = 5000 dbar
H3 = 2000 seconds.

Difference between the up and down cast oxygen was quite small for the 
pressure-hysteresis corrected RINKO data (Fig. 3.1.8).

The pressure-hysteresis corrected RINKO data was calibrated by the 
Stern-Volmer equation, basically according to a method by Uchida et al. 
(2008) with modification:

    [O2] (µmol/l) = [(V0 / V)2 - 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 exciting time (days) integrated from 
the first CTD cast. Time drift of the RINKO output was corrected. The 
pressure-compensation coefficient (Cp) was estimated to be 0.058. The 
coefficient for the V0 (C3 = -0.00076) was estimated from laboratory 
experiments on August 6, 2009. The remaining seven coefficients (C0, C1, C2, 
C4, C5, C6, and C7) were determined by minimizing the sum of absolute deviation 
with a weight from the bottle oxygen data. The revised quasi-Newton method 
(DMINF1) was used to determine the sets. The weight was given as a function 
of pressure as

    Weight = min[20, exp{log(20) x P / PR}], when [O2] ≥ 5 µmol/kg 
    Weight = 20, when [O2] < 5 µmol/kg, 

where PR is threshold of the pressure (950 dbar).

The post-cruise calibrated temperature and salinity data were used for the 
calibration. The coefficients were determined for some groups of the CTD 
stations. The calibration coefficients are listed in Table 3.1.7. The results 
of the post-cruise calibration for the RINKO oxygen are summarized in Table 
3.1.8 and shown in Fig. 3.1.9.


Figure 3.1.8: Difference between the up and down cast oxygen profiles from 
              RINKO, SBE 43, Optode 4330E and Optode 3830. (a) mean and (b) 
              standard deviation calculated from all CTD data.


Table 3.1.7: Calibration coefficients for the RINKO oxygen sensor.
________________________________________________________________________________________________

Group      C0           C1           C2           C4           C5          C6            C7
-----  -----------  ----------  ------------  -----------  ---------  ------------  ------------
Leg 1
  A    6.689376e-3  1.762279e-4  4.882030e-6  8.338279e-2  0.2267409  -4.196177e-3   3.326666e-3
  B    6.782221e-3  1.365800e-4  6.972649e-6  7.467877e-2  0.2304436  -2.522455e-3   2.283958e-3
  C    6.422881e-3  2.150534e-4  2.960990e-6  8.887120e-2  0.2285794  -7.967244e-5   8.759761e-4
  D    6.707974e-3  2.692866e-4  1.586005e-6  7.623816e-2  0.2298613  -1.307925e-4   8.577014e-4
  E    7.702781e-3  3.032778e-4  3.319508e-6  3.659057e-2  0.2395650  -3.795239e-4   5.390385e-4
  F    8.815933e-3  3.357220e-4  4.934811e-6  2.385302e-2  0.2267504  -1.456302e-3   1.483800e-3
Leg 2
  G    8.751177e-3  3.336450e-4  4.553403e-6 -4.679584e-2  0.2673914   2.997944e-3  -9.971862e-4
  H    8.835125e-3  3.345906e-4  5.044742e-6  1.583165e-2  0.2399865  -9.708137e-4   6.960351e-4
________________________________________________________________________________________________
        Group of CTD stations  A: 291-331,   B: 141-281,    C: 411-681,    D: 691-861,
                               E: 871-1481,  F: 1491-1561,  G: 1641-1721,  H: 1731-2881


Figure 3.1.9: Difference between the RINKO oxygen and the bottle oxygen after 
              the post-cruise calibration. Lower two panels show histogram of 
              the difference.


Table 3.1.8: Difference between the RINKO oxygen and the bottle oxygen after 
             the post-cruise calibration. Mean and standard deviation (Sdev) 
             are calculated for the data below and above 950 dbar Number of 
             data used is also shown.
      _________________________________________________________________

                Pressure ≥ 950 dbar           Pressure < 950 dbar
             ----------------------------  ----------------------------
      Leg    Number    Mean       Sdev     Number    Mean       Sdev
                     (µmol/kg)  (µmol/kg)          (µmol/kg)  (µmol/kg)
      -----  ------  ---------  ---------  ------  ---------  ---------
      Leg 1   2023     0.00       0.24      1781     0.07       1.67
      Leg 2   1357     0.01       0.28      1507     0.03       0.52
      _________________________________________________________________


(8) Estimation of tripped depth for the bottle #13 of stations P21_33_1 and P21_18_1

True tripped depths for the following miss tripped bottles were estimated by 
using post-cruise calibrated CTD salinity and oxygen data compared to the 
bottle sampled salinity and oxygen data (Table 3.1.9).


Table 3.1.9: Estimated pressure of tripped depth for miss tripped bottles. 
             The CTD temperature, salinity and oxygen data at the estimated 
             pressure are also shown.
  _________________________________________________________________________

                 Estimated pressure (dbar)    
    Bottle     -----------------------------   CTDTMP    CTDSAL    CTDOXY
               by CTDSAL  by CTDOXY  Average  (ITS-90)  (PSS-78)  (µmol/kg)
  -----------  ---------  ---------  -------  --------  --------  ---------
  P21_33_1#13   2403.0     2388.6    2395.8    1.9394   34.6628    134.45
  P21_18_1#13    762.2      763.2     762.7    5.6999   34.5179    28.86
  _________________________________________________________________________



REFERENCES

Fukasawa, M., T. Kawano and H. Uchida (2004): Blue Earth Global Expedition 
    collects CTD data aboard Mirai, BEAGLE 2003 conducted using a Dynacon CTD 
    traction winch and motion-compensated crane, Sea Technology, 45, 14-18.

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

Sea-Bird Electronics (2009): SBE 43 dissolved oxygen (DO) sensor - hysteresis 
    corrections, Application note no. 64-3, 7 pp.

Uchida, H., K. Ohyama, S. Ozawa, and M. Fukasawa (2007): In situ calibration 
    of the Sea-Bird 9plus CTD thermometer, J. Atmos. Oceanic Technol., 24, 
    1961-1967.

Uchida, H., T. Kawano, I. Kaneko, and M. Fukasawa (2008): In situ calibration 
    of optode-based oxygen sensors, J. Atmos. Oceanic Technol., 25,2271-2281.

Wetzel, R.G. and G.E. Likens (2000): Limnological Analysis, 429 pp., 
    Springer, New York, USA.




3.2  BOTTLE SALINITY
     September 9, 2009


(1) Personnel

    Takeshi Kawano   (JAMSTEC)
    Fujio Kobayashi  (MWJ)
    Tatsuya Tanaka   (MWJ)
    Akira Watanabe   (MWJ)
    Kenichi Katayama (MWJ)


(2) Objectives

Bottle salinities were measured to compare with CTD salinities for 
calibrating CTD salinities and for identifying leaking bottles.


(3) Instrument and Method

i. Salinity Sample Collection

The bottles in which the salinity samples are collected and stored are 250 ml 
Phoenix brown glass bottles with screw caps. Each bottle was rinsed three 
times with sample water and was filled to the shoulder of the bottle. The 
caps were also thoroughly rinsed. Salinity samples were stored more than 12 
hours in the same laboratory as the salinity measurement was made.

ii. Instruments and Method

The salinity analysis was carried out on Guildline Autosal salinometer model 
8400B (S/N 62556), which was modified by adding an Ocean Scientific 
International Ltd. peristaltic-type sample intake pump and two Guildline 
platinum thermometers model 9450. One thermometer monitored an ambient 
temperature and the other monitored a 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.

An ambient temperature varied from approximately 20°C to 24°C, while a bath 
temperature is very stable and varied within ± 0.002°C on rare occasion. A 
measure of a double conductivity ratio of a sample is 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 is smaller than 
0.00002, the average value of the two double conductivity ratios is used to 
calculate the bottle salinity with the algorithm for practical salinity 
scale, 1978 (UNESCO 1981). If the difference is grater than or equal to the 
0.00003, we measure another additional filling of the cell. In case where the 
double conductivity ratio of the additional filling does not satisfy the 
criteria above, we measure other additional fillings of the cell within 10 

fillings in total. In case where the number of fillings is 10 and those 
fillings do not satisfy the criteria above, the median of the double 
conductivity ratios of five fillings are used to calculate the bottle 
salinity.

The measurement was conducted about from 12 to 20 hours per day and the cell 
was cleaned with soap after the measurement of the day. We measured more than 
8,500 samples in total.



(4) Preliminary Result

i. Standard Seawater

Leg1 and Leg2a

Standardization control was set to 649 during Leg1 and Leg2a. The value of 
STANDBY was 5491 ± 0002 and that of ZERO was 0.00000 ± 0.00001. We used IAPSO 
Standard Seawater batch P150 which conductivity ratio was 0.99978 (double 
conductivity ratio is 1.99956) as the standard for salinity. We measured 219 
bottles of P150 during routine measurement. Fig.3.2.1 shows the history of 
double conductivity ratio of the Standard Seawater batch P150 during Legl and 
Leg2a.

Drifts were calculated by fitting data from P150 to the equation obtained by 
the least square method (solid lines). Correction for the double conductivity 
ration of the sample was made to compensate for the drift. After correction, 
the average of double conductivity ratio became 1.99956 and the standard 
deviation was 0.00001, which is equivalent to 0.0002 in salinity.


Figure 3.2.1: History of Double conductivity ratio of P150 during Leg1 and 
              Leg2a. X and Y axes represents date and double conductivity 
              ratio, respectively. Blue diamond is raw data and red 
              rectangular is corrected data.
Figure 3.2.2: History of Double conductivity ratio of P150 during Leg2b. X 
              and Y axes represents date and double conductivity ratio, 
              respectively. Blue diamond is raw data and red rectangular is 
              corrected data.


Leg2b

As the drift of this salinometer had been significant, the re-standardization 
was done on 27 May, and standardization control was set to 652 during Leg2b. 
The value of STANDBY was 5492 ± 0001 and that of ZERO was .00000 ± 0.00001. 
We used IAPSO Standard Seawater batch P150 which conductivity ratio was 
0.99978 (double conductivity ratio is 1.99956) as the standard for salinity. 
We measured 137 bottles of P150 during routine measurement. Fig.3.2.2 shows 
the history of double conductivity ratio of the Standard Seawater batch P150 
during Leg2b.

Drifts were calculated by fitting data from P150 to the equation obtained by 
the least square method (solid lines). Correction for the double conductivity 
ration of the sample was made to compensate for the drift. After correction, 
the average of double conductivity ratio became 1.99956 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 micrometer and stored in a 20 liter cubitainer made of 
polyethylene and stirred for at least 24 hours before measuring. It was 
measured every six samples in order to check the possible sudden drift of the 
salinometer. During the whole measurements, there was no detectable sudden 
drift of the salinometer.

iii. Replicate Samples

Leg1

We took 819 pairs of replicate during Legl. Fig.3.2.3 shows the histogram of 
the absolute difference between replicate samples. There was 1 bad 
measurement of replicate samples. Excluding these bad measurements, the 
standard deviation of the absolute deference of 818 pairs of replicate 
samples was 0.00023 in salinity.

                                   
Figure 3.2.3: The histogram of the absolute difference between replicate 
              samples in Leg1. X axis is absolute difference in salinity and 
              Y axis is frequency.
Figure 3.2.4: The histogram of the absolute difference between replicate 
              samples in Leg2. X axis is absolute difference in salinity and 
              Y axis is frequency.


Leg2

We took 613 pairs of replicate during Leg2. Fig.3.2.4 shows the histogram of 
the absolute difference between replicate samples. There was 1 bad 
measurement of replicate samples. Excluding these bad measurements, the 
standard deviation of the absolute deference of 612 pairs of replicate 
samples was 0.00019 in salinity.


(5) Further data quality check All the data will be checked once again in 
    detail with other parameters such as dissolved oxygen and nutrients.



REFERENCES

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

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




3.3  OXYGEN
     July 31, 2010


(1) Personnel

    Yuichiro Kumamoto (JAMSTEC)
    Miyo Ikeda        (MWJ)
    Fuyuki Shibata    (MWJ)
    Masanori Enoki    (MWJ)
    Misato Kuwahara   (MWJ)


(2) Objectives

Dissolved oxygen is one of good tracers for the ocean circulation. Recent 
studies indicated that the 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 MR09-01, we 
measured dissolved oxygen concentration from surface to bottom layers at all 
the hydrocast stations along approximately 18°S in the tropical South 
Pacific. These stations reoccupied the WOCE Hydrographic Program (WHP) P21 
stations in 1994. Our purpose is to evaluate temporal change in dissolved 
oxygen concentration in the tropical South Pacific between the 1994 and 2009.


(3) Reagents

Pickling Reagent I: Manganous chloride solution (3M)
Pickling Reagent II: Sodium hydroxide (8M) / sodium iodide solution (4M)
Sulfuric acid solution (5M)
Sodium thiosulfate (0.025M)
Potassium iodate (0.001667M)
CSK standard of potassium iodate: Lot T5K3592, Wako Pure Chemical Industries 
    Ltd., 0.0100N


(4) Instruments

Burette for sodium thiosulfate and potassium iodate: APB-510 manufactured by 
    Kyoto Electronic Co. Ltd. / 10 cm3 of titration vessel
Detector: Automatic photometric titrator, DOT-01 manufactured by Kimoto 
    Electronic Co. Ltd.


(5) Seawater sampling

Following procedure is based on an analytical method, entitled by 
"Determination of dissolved oxygen in sea water by Winkler titration", in the 
WHP Operations Manual (Dickson, 1996). Seawater samples were collected from 
12-liters Niskin sampler bottles attached to the CTD-system. Seawater for 
bottle oxygen measurement was transferred from the Niskin sampler bottle to a 
volume calibrated glass flask (ca. 100 cm3) . Three times volume of the flask 
of seawater was overflowed. Sample temperature was measured by a thermometer 
during the overflowing. Then two reagent solutions (Reagent I, II) of 0.5 cm3 
each were added immediately into the sample flask and the stopper was 
inserted carefully into the flask. The sample flask was then shaken 
vigorously to mix the contents and to disperse the precipitate finely 
throughout. After the precipitate has settled at least halfway down the 
flask, the flask was shaken again to disperse the precipitate. The sample 
flasks containing pickled samples were stored in a laboratory until they were 
titrated.


(6) Sample measurement

At least two hours after the re-shaking, the pickled samples were measured on 
board. A magnetic stirrer bar and 1 cm3 sulfuric acid solution were added into 
the sample flask and stirring began. Samples were titrated automatically by 
sodium thiosulfate solution whose molarity was determined by standard 
solution of potassium iodate (see section 7). Temperature of sodium 
thiosulfate during titration was recorded by a thermometer. We measured 
dissolved oxygen concentration using two sets of the titration apparatus, 
named DOT-1 and DOT-2.

Dissolved oxygen concentration (µmol/kg-1) was calculated by the sample 
temperature during the sampling, CTD salinity, flask volume, and the titrant 
concentration and volume corrected with burette-volume calibration. When we 
measured suboxic samples (oxygen concentration less than about 40 µmol/kg-1), 
titration procedure was adjusted manually. In case of anoxic sample 
measurements (oxygen concentration less than about 6 µmol/kg-1), titration 
volume of sodium thiosulfate titrant was not corrected with the 
burette-volume calibration.


(7) Standardization

Concentration of sodium thiosulfate titrant (ca. 0.025M) was determined by 
potassium iodate solution. Pure potassium iodate (Lot TSK3592, Wako Pure 
Chemical Industries Ltd., 99.96±0.01%) was dried in an oven at 130°C. 1.7835 
g potassium iodate weighed out accurately was dissolved in deionized water 
and diluted to final volume of 5 dm3 in a calibrated volumetric flask 
(0.001667M). 10 cm3 of the standard potassium iodate solution was added to a 
flask using a volume-calibrated dispenser. Then 90 cm3 of deionized water, 1 
cm3 of sulfuric acid solution, and 0.5 cm3 of pickling reagent solution II and 
I were added into the flask in order. Amount of titrated volume of sodium 
thiosulfate (usually 5 times measurements average) gave the molarity of the 
sodium thiosulfate titrant (Table 3.3.1). Error (C.V.) of the standardization 
was 0.02±0.01%, or c.a. 0.05 µmol/kg-1.


(8) Determination of the blank

The oxygen in the pickling reagents 1(0.5 cm3) and 11(0.5 cm3) was assumed to 
be 3.8 x 108 mol (Murray et al., 1968). The blank due to other than oxygen 
was determined as follows. 1 and 2 cm3 of the standard potassium iodate 
solution were added to two flasks respectively. Then 100 cm3 of deionized 
water, 1 cm3 of sulfuric acid solution, and 0.5 cm3 of pickling reagent 
solution II and I each were added into the two flasks in order. The blank was 
determined by difference between the two times of the first (1 cm3 of KIO3) 
titrated volume of the sodium thiosulfate and the second (2 cm3 of KIO3) one. 
The results of 3 times blank determinations were averaged (Table 3.3.1). The 
averaged blank values for DOT-1 and DOT-2 were -0.002±0.001 (S.D., n=27) and 
-0.000±0.001 (S.D., n=27) cm3, respectively. The blank determined here can 
cancel a sum of errors due to oxidants or reductants in the reagents, 
differences between the measured end-point and the equivalence point, and 
oxidation of iodide to iodate with the atmospheric O2 during the titration. 
However, blank due to redox species other than oxygen in seawater sample, 
called "seawater blank", still remains in the Winkler oxygen concentration.


Table 3.3.1: Results of the standardization and the blank determinations 
             during MR09-01.
___________________________________________________________________________________________________

               KIO3 standard     Na2S2O3          DOT-1         DOT-2  
  Date     #   --------------  ------------  -------------  -------------         Stations
  (UTC)            ID No.                     E.P.   blank   E.P.   blank  
---------  --  --------------  ------------  -----  ------  -----  ------  ------------------------
2009/4/13      20081203-11-02  20080704-2-1  3.957  -0.001  3.957  -0.001  029,030,031,032,040,033
2009/4/18      20081203-11-03  20080704-2-1  3.958   0.001  3.959   0.003  -
2009/4/18  11  20081203-11-04  20080704-2-2  3.958  -0.002  3.957  -0.002  -
2009/4/21      20081203-11-05  20080704-2-2  3.956  -0.001  3.956   0.001  041,034,042,035
2009/4/22      20081203-11-07  20080704-3-1  3.960  -0.002  3.960  -0.001  043,036,044,037,045,038, 
                                                                           046,039
---------------------------------------------------------------------------------------------------
2009/4/24      20081203-12-02  20080704-3-1  3.962  -0.002  3.962  -0.001  047,X19,049,050
2009/4/25      20081203-12-03  20080704-3-2  3.961  -0.002  3.964   0.001  054,051,055,056,053,057, 
                                                                           058,059,060,061,062,063, 
                                                                           064,065
2009/4/26      20081203-12-04  20080704-3-2  3.962  -0.002  3.961   0.000  052
2009/4/28  12  20081203-12-06  20080704-4-1  3.963  -0.002  3.962   0.000  066,067,068,069,070,071, 
                                                                           072,073,074,075,076,X18, 
                                                                           077,078
2009/5/1       20081203-12-08  20080704-4-2  3.963  -0.002  3.964  -0.001  079,080,085,086,087,088, 
                                                                           089,090,095,096,097-2, 
                                                                           098,099,100
2009/5/5       20081203-12-10  20080704-5-1  3.964  -0.002  3.964   0.000  101,102,103,104,105,106
---------------------------------------------------------------------------------------------------
2009/5/6       20081203-13-01  20080704-5-1  3.962  -0.001  3.962   0.000  107,108,109,110,111,112, 
                                                                           113,114
2009/5/8       20081203-13-02  20080704-5-2  3.965  -0.002  3.964  -0.001  115,116,117,118,119,120, 
                                                                           121,122,123,124,125,126, 
                                                                           127
2009/5/11  13  20081203-13-04  20080704-6-1  3.964  -0.001  3.964   0.000  128,129,130,X17,131,132, 
                                                                           133,134,135,136,137
2009/5/14      20081203-13-06  20080704-6-2  3.964  -0.002  3.964  -0.001  138,139,140,141,142,143, 
                                                                           144,145,146,147,148,149, 
                                                                           150,151,152
2009/5/16      20081203-13-08  20080704-7-1  3.963  -0.001  3.965   0.000  153,154,155,160,159,158, 
                                                                           157,156
---------------------------------------------------------------------------------------------------
2009/5/21      20081203-14-01  20080704-7-2  3.963  -0.003  3.965  -0.003  164,165,X16,167,168,169, 
                                                                           170,171,172
2009/5/26      20081203-14-03  20080704-8-1  3.968  -0.001  3.971   0.001  173,174,175,176,177,178, 
                                                                           179,180,181,182,183
2009/5/29  14  20081203-14-05  20080704-8-2  3.968  -0.001  3.969  -0.001  184,185,186,187,188,189, 
                                                                           190,191,192
2009/6/1       20081203-14-07  20080704-9-1  3.965  -0.001  3.965  -0.001  193,194,195,196,197,198, 
                                                                           199,200,201,203,204,205
2009/6/3       20081203-14-09  20080704-9-2  3.965  -0.002  3.966   0.000  206,207,208,209,210,211, 
                                                                           212,213
---------------------------------------------------------------------------------------------------
2009/6/5      20081203-15-01  20080704-9-2   3.963  -0.002  3.964   0.000  214,215,216,217,218,220, 
                                                                           221,222
2009/6/6      20081203-15-03  20080704-10-1  3.975  -0.001  3.976   0.001  223,224,225,226,227,228, 
           15                                                              229,230,231,232,233
2009/6/9      20081203-15-05  20080704-10-2  3.977  -0.001  3.978   0.002  234,235,236,237,238,239, 
                                                                           240,241,243,244,245,246
2009/6/10     20081203-15-07  20080704-11-1  3.965  -0.001  3.965   0.000  247,248,249,250,251,252, 
                                                                           253,255,254
---------------------------------------------------------------------------------------------------
2009/6/13     20081204-16-01  20080704-11-2  3.967  -0.002  3.968   0.000  260,261,262,263,264,265, 
                                                                           266,267,268,269,270,271, 
           16                                                              272,273,274,275,276
2009/6/16     20081204-16-03  20080704-12-1  3.966  -0.002  3.967   0.000  277,278,279,280,281,282, 
                                                                           283,285,287,286,288
___________________________________________________________________________________________________
# Batch number of the KIO3 standard solution


(9) Replicate sample measurement

Replicate samples were taken from every CTD cast. Total amount of the 
replicate sample pairs of good measurement (flagged 2) was 656. The standard 
deviation of the replicate measurement was 0.09 µmol kg-1 that was calculated 
by a procedure (SOP23) in DOE (1994). The replicate measurements depended on 
neither measurement date nor sampling depth (Fig.3.3.1). Each set of "good" 
data from replicate sample pairs were averaged and then flagged 2 (see 
section 12).


Figure 3.3.1: Differences ((µmol kg-1)2) of replicate sample pairs against the 
              Julian days (a) and sampling depth (b).


(10) Duplicate sample measurement

Duplicate samples were taken from 27 CTD casts during this cruise. The 
standard deviation of the duplicate measurements was calculated to be 0.07 
µmol kg-1 which was equivalent with that of the replicate measurements (0.09 
µmol kg-1). We concluded that the precision of our oxygen measurement through 
this cruise, including errors from the seawater sampling, pickling, and the 
Winkle titration, were about 0.1 µmol kg-1.


(11) CSK standard measurements

The CSK standard is a commercial potassium iodate solution (0.0100 N) for 
analysis of dissolved oxygen. Before the cruise, we titrated the CSK standard 
solutions (Lot TSK3592) against all the six batch series (#11-#16) of our KIO3 
standard solution (see section 7) which had been prepared for this cruise. In 
addition, the CSK solution was also measured at the beginning, mid, and end 
of the cruise. The results of the CSK are shown in Table 3.3.2. A good 
agreement among them confirms that there was no systematic shift in our 
oxygen analyses on board. We also confirmed that there was not difference in 
the results between the current (TSK3592) and former (EWL3818) batches of the 
CSK standard solutions which were applied to this cruise and previous ones in 
2007 (MR07-04 and MR07-06), respectively. This agreement indicates 
comparability in the oxygen data between 2007 and 2009.


Table 3.3.2: Results of the CSK standard (Lot TSK3592) measurements.
_____________________________________________________________________________________

                                 DOT-3                     -
Date (UTC)   KIO3 ID No.    --------------------  --------------------     Remarks
                            Conc. (N)  error (N)      -          - 
----------  --------------  ---------  ---------  ---------  ---------  -------------
2008/12/08  20081203-11-12  0.010000   0.000002       -          -      before cruise
2008/12/08  20081203-12-12  0.010001   0.000002       -          -      before cruise
2008/12/08  20081203-13-12  0.010001   0.000002       -          -      before cruise
2008/12/08  20081203-14-12  0.009999   0.000002       -          -      before cruise
2008/12/08  20081203-15-12  0.009999   0.000002       -          -      before cruise
2008/12/09  20081203-16-12  0.010001   0.000003       -          -      before cruise

                                    DOT-1                 DOT-2
Date (UTC)   KIO3 ID No.    --------------------  --------------------     Remarks
                            Conc. (N)  error (N)  Conc. (N)  error (N) 
----------  --------------  ---------  ---------  ---------  ---------  -------------
2009/04/10  20081203-11-01  0.010003   0.000002   0.010008   0.000001   MR09-01 Leg-1
2009/05/18  20081203-13-09  0.010008   0.000001   0.010003   0.000003   MR09-01 Leg-1
2009/06/18  20081204-16-04  0.010005   0.000007   0.010002   0.000002   MR09-01 Leg-2
_____________________________________________________________________________________


(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 3.3.3). 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 (see section 9). For the choice between 2, 3, or 4, we 
basically followed a flagging procedure as listed below:

  a. Bottle oxygen concentration was plotted against sampling pressure. Any 
     points not lying on a generally smooth trend were noted.
  b. Difference between the bottle oxygen and CTD oxygen was then plotted 
     against sampling pressure. If a datum deviated from a group of plots, it 
     was flagged 3.
  c. Vertical transections 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 7 (unknown problem), a 
     datum was flagged based on steps a, b, c, and d.


Table 3.3.3: Summary of assigned quality control flags.
                      ___________________________________

                      Flag  Definition  
                      ----  ----------------------  ----
                       2    Good                    6319
                       3    Questionable              30
                       4    Bad                       29
                       5    Not reported (missing)     0
                      Total                         6378
                      ___________________________________



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 seawater; 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, and V. Mohrholz (2008): Expanding 
    Oxygen-Minimum Zones in the Tropical Oceans, Science, 320, 655-668.




3.4  NUTRIENTS
     September 1, 2010


(1) Personnel

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

    LEG 1
    Ayumi Takeuchi      (Department of Marine Science, Marine Works Japan Ltd.)
    Shinichiro Yokogawa (Department of Marine Science, Marine Works Japan Ltd.)
    Kohei Miura         (Marine Works Japan Ltd.)

    LEG 2
    Junji Matsushita    (Department of Marine Science, Marine Works Japan Ltd.)
    Ayumi Takeuchi      (Department of Marine Science, Marine Works Japan Ltd.)
    Kohei Miura         (Marine Works Japan Ltd.)


(2) Objectives

The objectives of nutrients analyses during the R/V Mirai MR0901 cruise, WOCE 
P21 revisited cruise in 2009, in the North Pacific are as follows;

  • Describe the present status of nutrients concentration with excellent 
    comparability.
  • The determinants are nitrate, nitrite, phosphate and silicate.
  • Study the temporal and spatial variation of nutrients concentration based 
    on the previous high quality experiments data of WOCE previous P21 
    cruises in 1994, GEOSECS, IGY and so on.
  • Study of temporal and spatial variation of nitrate: phosphate ratio, so 
    called Redfield ratio.
  • Obtain more accurate estimation of total amount of nitrate, phosphate and 
    silicate in the interested area.
  • Provide more accurate nutrients data for physical oceanographers to use 
    as tracers of water mass movement.


(3) Summary of nutrients analysis

We made 233 TRAACS800 runs for the samples at 243 stations in MR0901. The 
total amount of layers of the seawater sample reached up to 6369 for MR0901. 
We made duplicate measurement at all layers.


(4) Instrument and Method


(4.1) Analytical detail using TRAACS 800 systems (BRAN+LUEBBE)

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

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

The silicate method is analogous to that described for phosphate. The method 
used is essentially that of Grasshoff et al. (1983), wherein silicomolybdic 
acid is first formed from the silicate in the sample and added molybdic acid; 
then the silicomolybdic acid is reduced to silicomolybdous acid, or 
"molybdenum blue," using ascorbic acid as the reductant. The analytical 
methods of the nutrients during this cruise are same as the methods used in 
(Kawano et al. 2009). We, though, changed the rate of NED in channel 2 from 
WHT/WHT to RED/RED to increase stability of the analysis. We also made slight 
change in NED regent that we add Triton(R) X-100 as shown in (4.3) Nitrite 
Regents. The flow diagrams and reagents for each parameter are shown in 
Figures 3.4.1 to 3.4.4.


(4.2) Nitrate Reagents 

      Imidazole (buffer), 0.06 M (0.4% w/v) 
        Dissolve 4 g imidazole, C3H4N2, in ca. 1000 ml DIW; add 2 ml 
        concentrated HCl. After mixing, 1 ml Triton(R) X-100 (50% solution in 
        ethanol) is added.

      Sulfanilamide, 0.06 M (1% w/v) in 1.2M HCl 
        Dissolve 10 g sulfanilamide, 4-NH2C6H4SO3H, in 900 ml of DIW, add 100 
        ml concentrated HCl. After mixing, 2 ml Triton(R)X-100 (50%f solution 
        in ethanol) is added.

      N-1-Napthylethylene-diamine dihydrochloride, 0.004 M (0.1%f w/v) 
        Dissolve 1 g NEDA, C10H7NHCH2CH2NH2 2HC1, 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 3.4.1: 1ch. (NO3+NO2) Flow diagram


(4.3) Nitrite Reagents 

      Sulfanilamide, 0.06 M (1% w/v) in 1.2 M HC1 
        Dissolve l0g sulfanilamide, 4-NH2C6H4SO3H, in 900 ml of DIW, add 100 ml 
        concentrated HC1. 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 2HC1, in 1000 ml of DIW and add 10 
        ml concentrated HC1. After mixing, 1 ml Triton(R)X-100 (50%f solution 
        in ethanol) is added. Stored in a dark bottle.


Figure 3.4.2:  2ch. (NO2) Flow diagram


(4.4) Silicate Reagents Molybdic acid, 0.06 M (2% w/v) 
        Dissolve 15 g Disodium Molybdate(VI) Dihydrate, Na2MoO4 2H20, 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) 
        Dissolve 50 g Oxalic Acid Anhydrous, HOOC: COOH, in 950 ml of DIW.

      Ascorbic acid, 0.01 M (3% w/v)
        Dissolve 2.5 g L (+)-Ascorbic Acid, C6H806, in 100 ml of DIW. Stored in 
        a dark bottle and freshly repaired before every measurement.


Figure 3.4.3: 3ch. (5i02) Flow diagram.


(4.5) Phosphate Reagents 

      Stock molybdate solution, 0.03 M (0.8% w/v) 
        Dissolve 8 g Disodium Molybdate(VI) Dihydrate, Na2MoO4 2H2O, and 0.17 g 
        Antimony Potassium Tartrate, C8H4K2O12Sb2 3H20, in 950 ml of DIW and add 
        50 ml concentrated H2S04.

      Mixed Reagent
        Dissolve 0.8 g L (+)-Ascorbic Acid, C6H8O6, in 100 ml of stock 
        molybdate solution. After mixing, 2 ml sodium dodecyl sulphate (15% 
        solution in water) is added. Stored in a dark bottle and freshly 
        prepared before every measurement.

      Reagent for sample dilution 
        Dissolve Sodium Hydrate, NaC1, 10 g in ca. 950 ml of DIW, add 50 ml 
        Acetone and 4 ml concentrated H25O4. After mixing, 5 ml sodium dodecyl 
        sulphate (15% solution in water) is added.


Figure 3.4.4: 4ch. (PO4) Flow diagram.


(4.6) Sampling procedures

Sampling of nutrients followed that oxygen, trace gases and salinity. Samples 
were drawn into two of virgin 10 ml polyacrylates vials without sample 
drawing tubes. These were rinsed three times before filling and vials were 
capped immediately after the drawing. The vials are put into water bath 
adjusted to ambient temperature, 25 ± 1°C, in 10 to 20 minutes before use to 
stabilize the temperature of samples in MR0901.

No transfer was made and the vials were set an auto sampler tray directly. 
Samples were analyzed after collection basically within 17 hours in MR0901.


(4.7) Data processing

      Raw data from TRAACS800 were treated as follows;

      • Check baseline shift.
      • Check the shape of each peak and positions of peak values taken, and 
        then change the positions of peak values taken if necessary.
      • Carry-over correction and baseline drift correction were applied to 
        peak heights of each samples followed by sensitivity correction.
      • Baseline correction and sensitivity correction were done basically 
        using liner regression.
      • Load pressure and salinity from CTD data to calculate density of 
        seawater.
      • Calibration curves to get nutrients concentration were assumed second 
        order equations.


(5) Nutrients standards


(5.1) Volumetric Laboratory Ware of in-house standards

All volumetric glass 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 phosphate standard, "potassium dihydrogen phosphate anhydrous 99.995 
suprapur" provided by Merck, CAS No. 7778-77-0, was used.

For nitrite standard, "sodium nitrate" provided by Wako, CAS No. 7632-00-0, 
was used. And assay of nitrite was determined according JIS K8019 and assays 
of nitrite salts were 98.04%. 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 
HC75 1838 is used. The silicate concentration is certified by NIST-SRM3 150 
with the uncertainty of 0.5%.

Ultra pure water

Ultra pure water (MilliQ water) freshly drawn was used for preparation of 
reagents, higher concentration standards and for measurement of reagent and 
system blanks.

Low-Nutrient Seawater (LNSW)

Surface water having low nutrient concentration was taken and filtered using 
0.45 gm 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 Jul2008.


(5.3) Concentrations of nutrients for A, B and C standards

Concentrations of nutrients for A, B and C standards are set as shown in 
Table 3.4.1. The C standard is prepared according recipes as shown in Table 
3.4.2. All volumetric laboratory tools were calibrated prior the cruise as 
stated in chapter (i). Then the actual concentration of nutrients in each 
fresh standard was calculated based on the ambient, solution temperature and 
determined factors of volumetric lab. wares.

The calibration curves for each run were obtained using 6 levels, C-1, C-2, 
C-3, C-4, C-S and C-6. For the 10 stations from station 233 to station 245, 
we used only five levels, from C-1 to C-5 because silicate concentration of 
C-6 for these stations might be higher rather than target concentration. For 
the 19 runs, we used only five levels because nutrients concentration of one 
of the RMs was outliter.


Table 3.4.1:  Nominal concentrations of nutrients for A, B and C standards.
             ___________________________________________________

                         A      B   C-1  C-2  C-3  C-4  C-S  C-6
                       -----  ----  ---  ---  ---  ---  ---  ---
             NO3(µM)   45000   900  AS   BJ   AX   BE   AZ    55
             NO2(µM)    4000    20  AS   BJ   AX   BE   AZ   1.2
             SiO2(µM)  36000  2880  AS   BJ   AX   BE   AZ   170
             PO4(µM)    3000    60  AS   BJ   AX   BE   AZ   3.6
             ___________________________________________________


Table 3.4.2: Working calibration standard recipes.
                       ________________________________

                       C Std.    B-1 Std.     B-2 Std.
                       ------    --------    ----------
                        C-6        30m1         30m1

                       B-1 Std.: Mixture of nitrate, 
                                 silicate and phosphate
                       B-2 Std.: Nitrite
                       ________________________________


(5.4) Renewal of in-house standard solutions.

In-house standard solutions as stated in (iii) were renewed as shown in Table 
3.4.3(a) to (c).


Table 3.4.3(a): Timing of renewal of in-house standards.
          _________________________________________________________

              NO3, NO2, Si02, P04                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 3.4.3(b):  Timing of renewal of in-house standards.
              _________________________________________________

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


Table 3.4.3(c):  Timing of renewal of in-house standards.
                 ___________________________________________

                 Reduction estimation         Renewal
                 --------------------  ---------------------
                 D-1 Std.(7200µM NO3)  when A-1 Std. renewed
                       43/µM NO3        when C Std. renewed
                       47/µM 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). In the previous world wide expeditions, such as WOCE 
cruises, the higher reproducibility and precision of nutrients measurements 
were required (Joyce and Corry, 1994). Since no standards were available for 
the measurement of nutrients in seawater at that time, the requirements were 
described in term of reproducibility. The required reproducibility was 1%, 1 
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°C in potential temperature (Aoyama and Joyce, 1996).


(6.1) RMNSs for this cruise

RMNS lots AS, BJ, AX, BE and AZ, which cover full range of nutrients 
concentrations in the western North Pacific Ocean are prepared. 160 sets of 
AS, BJ, AX, BE and AZ are prepared.

Three hundred ten bottles of RMNS lot BI and 200 bottles of RMNS lot AV are 
prepared for MR09Oi. Lot BI was used at 99 stations from 14 to 120 and lot AV 
was used at 158 stations from 121 to 288, respectively. These RMNS assignment 
were completely done based on random number. The RMNS bottles were stored at 
a room in the ship, REAGENT STORE, where the temperature was maintained 
around 24°C.


(6.2) Assigned concentration for RMNSs

We assigned nutrients concentrations for RMNS lots AS, BJ, AX, BE, AZ, BI and 
AV as shown in Table 3.4.4.


Table 3.4.4:  Assigned concentration of RMNSs. 

                                                  unit: µmol kg-1
                 ___________________________________________

                       Nitrate  Phosphate  Silicate  Nitrite
                       -------  ---------  --------  -------
                 AS*     0.11     0.077       1.58    0.02
                 BJ*     7.74     0.628      31.04    0.02
                 AX**   21.42     1.619      58.06    0.35
                 BE*    36.70     2.662      99.20    0.03
                        42.36     3.017     133.93    0.03
                 BI*    41.36     2.576     147.51    0.02
                 AV**   33.36     2.516     154.14    0.10
                 ___________________________________________
                  * The value in the Table is result of mea-
                    surement on 6 January, 2009.
                 ** The value in the Table is result of mea-
                    surement on 7 October, 2007.


(6.3) The homogeneity of RMNSs

The homogeneity of lot AV and AZ used in MR0901 cruise and analytical 
precisions are shown in Table 3.4.5. These are for the assessment of the 
magnitude of homogeneity of the RMNS bottles those are used during the 
cruise. As shown in Table 3.4.5 homogeneity of RMNS lot AV and AZ for 
nitrate, phosphate and silicate are the same magnitude of analytical 
precision derived from fresh raw seawater in January 2009.


Table 3.4.5:  Homogeneity of lot AV and AZ derived from simultaneous 297 
              samples measurements and analytical precision onboard R/V Mirai 
              in MR0901.
              _________________________________________________

                                   Nitrate  Phosphate  Silicate
                                     CV%       CV%       CV%
                                   -------  ---------  --------
              AV                    0.09      0.12       0.08
              AZ                    0.13      0.15       0.08
              Precision             0.08      0.10       0.07
              AV: N=297 AZ: N=244      
              _________________________________________________


We can see history of homogeneity of several lots of RMNS as shown in Table 
3.4.6. The homogeneity of phosphate in old lots such as lot AH and K were 
relatively larger than those of recent lots, BI and BC. The homogeneities of 
nitrate and silicate, we also see progress from lot K to recent lots.


Table 3.4.6:  History of homogeneity of lot BI and previous lots derived from 
              simultaneous 30 samples measurements and analytical precision 
              onboard R/V Mirai in January 2009.
                   _______________________________________

                              Nitrate  Phosphate  Silicate
                                CV%       CV%       CV%
                              -------  ---------  --------
                   BI          0.19      0.21      0.08
                   BC*         0.22      0.32      0.19
                   AH*         0.39      0.83      0.13
                   K*          0.3       1.0       0.2
                   Precision   0.18      0.14      0.07
                   _______________________________________
                   * Table 3.4.5 in WHP P01, P14 REVISIT 
                     DATA BOOK (Kawano et al. 2009)  


(6.4) Comparability of RMNSs during the periods from 2003 to 2009

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 3.4.7, the nutrients 
concentrations of RMNSs were in good agreement among the measurements during 
the period from 2003 to 2009. For the silicate measurements, we show lot 
numbers and chemical company names of each cruise / measurement in the 
footnote. As shown in Table 3.4.7, there shows less comparability among the 
measurements due to less comparability among the standard solutions provided 
by chemical companies in the silicate measurements.


Table 3.4.7 (a):  Comparability for nitrate. 
                                                                          NITRATE                                       µmol kg-1
                                                                          RM Lots
_______________________________________________________________________________________________________________________________

Cruise / Lab.           |  AH   | unc. |  AZ   | unc. |  BA  | unc. |  AX   | unc. |  AV   | unc. |  BC   | unc. |  BE   | unc.
----------------------- | ----- | ---- | ----- | ---- | ---- | ---- | ----- | ---- | ----- | ---- | ----- | ---- | ----- | ----
         2003           |       |      |       |      |      |      |       |      |       |      |       |      |       |     
2003intercomp_repeorted | 35.23 | 0.06 |       |      |      |      | 21.39 |      |       |      |       |      |       |     
MR03-K04 Legl           | 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 |       |      |       |     
________________________________________________________________________________________________________________________________



Table 3.4.7 (b):  Comparability for phosphate. 
                                                                         PHOSPATE                                       µmol kg-1
                                                                         RM  Lots
_____________________________________________________________________________________________________________________________________

Cruise / Lab.         |  AH   |  unc. |  AZ   |  unc. |   BA  |  unc. |  AX   |  unc. |  AV   |  unc. |  BC   |  unc. |  BE   | unc.
--------------------- | ----- | ----- | ----- | ----- | ----- | ----- | ----- | ----- | ----- | ----- | ----- | ----- | ----- | ----
         2003         |       |       |       |       |       |       |       |       |       |       |       |       |       | 
2003intercomp         | 2.141 | 0.001 |       |       |       |       |       |       |       |       |       |       |       |
MRO3-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_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 |       |       |       |
_____________________________________________________________________________________________________________________________________



Table 3.4.7 (C):  Comparability for silicate. 
                                                                          SILICATE                                       µmol kg-1
                                                                          RM Lots
____________________________________________________________________________________________________________________________________

Cruise / Lab.           |   AH   | unc. |   AZ   | unc. |  BA  | unc. |  AX   | unc. |   AV   | unc. |   BC   | unc. |  BE   | unc.
----------------------- | ------ | ---- | ------ | ---- | ---- | ---- | ----- | ---- | ------ | ---- | ------ | ---- | ----- | ----
         2003           |        |      |        |      |      |      |       |      |        |      |        |      |       |     
2003mtercomp *          | 130.51 | 0.20 |        |      |      |      |       |      |        |      |        |      |       |     
MRO3-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 |       |     
MRO7-04$$               |        |      |        |      | 1.62 | 0.07 | 58.11 | 0.11 | 154.45 | 0.21 | 156.62 | 0.48 |       |     
MRO7-06_1 precruise$$   | 133.02 | 0.09 |        |      | 1.64 | 0.00 | 58.50 | 0.04 | 155.06 | 0.11 | 156.33 | 0.11 |       |     
MRO7-06_2 precruise$$   | 132.70 | 0.07 |        |      | 1.56 | 0.00 | 58.25 | 0.03 | 154.39 | 0.08 | 156.57 | 0.08 |       |     
MRO7-06_1$$             |        |      |        |      | 1.61 | 0.04 | 58.13 | 0.08 | 154.48 | 0.13 | 156.64 | 0.08 |       |     
MRO7-06_2$$             |        |      |        |      | 1.58 | 0.07 | 58.04 | 0.10 | 154.38 | 0.16 | 156.61 | 0.13 |       |     
         2008           |        |      |        |      |      |      |       |      |        |      |        |      |       |     
2008intercomp‡          |        |      |        |      | 1.64 | 0.00 | 58.17 | 0.05 |        |      |        |      |       |     
2006intercomp_re‡       |        |      | 134.11 | 0.11 | 1.65 | 0.00 | 58.26 | 0.05 | 154.36 | 0.12 |        |      |       |     
2003intercomp_re‡       | 132.11 | 0.11 |        |      |      |      |       |      |        |      |        |      |       |     
         2009           |        |      |        |      |      |      |       |      |        |      |        |      |       |     
MR09-01_0 precruise‡    |        |      | 133.93 | 0.04 | 1.57 | 0.00 | 58.06 | 0.02 | 154.23 | 0.05 | 156.16 | 0.05 | 99.20 | 0.03
MR09-01_1‡              |        |      | 133.97 | 0.11 | 1.34 | 0.11 | 58.15 | 0.08 | 154.48 | 0.09 | 155.89 | 0.13 | 99.24 | 0.08
MR09-01_2‡              |        |      | 133.96 | 0.11 |      |      | 58.19 | 0.08 | 154.42 | 0.12 |        |      | 99.23 | 0.08
INSS stability test_1‡‡ | 132.40 | 0.35 |        |      | 1.69 | 0.02 | 58.18 | 0.02 | 154.43 | 0.09 |        |      |       |     
____________________________________________________________________________________________________________________________________
List of lot numbers: *: Kanto 306F9235;   **: Kanto 402F9041;   #: Kanto 507F9205;   ##: Kanto 609F9157; 
                     $: Merck 0C551722;   $$: Merck HC623465;   ‡: Merck HC751838;   ‡‡: HC814662


(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. There is exception for the number of the 
measurements that are used to evaluate analytical precision of silicate at 10 
runs from stations 233 to 245 where we evaluate analytical precision based on 
6 to 8 measurements. Summary of precisions are shown as shown in Table 3.4.8 
and Figures 3.4.5 to 3.4.7, 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 3.4.6. 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 0.08% for nitrate, 0.10% for phosphate and 0.07% for silicate 
in terms of median of precision, respectively. Then we can conclude that the 
analytical precisions for nitrate, phosphate and silicate were maintained 
throughout this cruise. The time series of precision are shown in Figures 
3.4.5 to 3.4.7.


Table 3.4.8: Summary of precision based on the replicate analyses.
                     _____________________________________

                              Nitrate  Phosphate  Silicate
                                CV%       CV%        CV%
                              -------  ---------  --------
                     Median    0.08      0.10       0.07
                     Mean      0.08      0.10       0.08
                     Maximum   0.18      0.17       0.14
                     Minimum   0.02      0.04       0.02
                     N          265       265       263
                     _____________________________________


Figure 3.4.5: Time series of precision of nitrate for MR0901.
Figure 3.4.6: Time series of precision of phosphate for MR0901
Figure 3.4.7: Time series of precision of silicate for MR0901.


(7.2) Carry over

We can also summarize the magnitudes of carry over throughout the cruise. 
These are small enough within acceptable levels as shown in Table 3.4.10.


Table 3.4.10: Summary of carry over through out MR0901 cruise.
                     _____________________________________

                              Nitrate  Phosphate  Silicate
                                CV%       CV%       CV%
                              -------  ---------  --------
                     Median    0.21      0.24      0.20
                     Mean      0.21      0.23      0.20
                     Maximum   0.38      0.53      0.33
                     Minimum   0.03      0.01      0.03
                     N          237       237       237
                     _____________________________________


(7.3) Dilution for shallower samples by lot AZ.

We decided to dilute 41 samples from shallower layers as shown Table 3.4.11 
due to higher nitrite concentration which exceed 2 µmol kg-1. We add 5.060 ml 
of lot AZ to 0.504 ml of sample. Therefore, uncertainties of the nutrients 
concentration of diluted samples were larger compared with non-diluted 
samples.

Table 3.4.11: Summary of diluted samples.
                  ________________________________________

                  Station  Pressure (dbar)
                  -------  -------------------------------
                     29    10, 50, 100, 150, 200, 250, 280
                     30    10, 50, 100, 150, 200, 250, 300
                     31    10, 50, 100, 150, 200, 250, 330
                     32    150, 200, 250, 280
                     35    280
                     40    150, 200, 250, 300
                     41    250,280
                     43    250,300
                     46    200,250
                     51    100
                     67    100
                     68    100
                    143    150
                    144    150
                  ________________________________________


(7.4) Possible concentration change of lot AV 

We found that nutrients concentrations of RM-AV were about 0.5% higher rather 
than those we assigned before cruise as shown in Table 3.4.4. The reasons of 
this increase are not clear yet, it might occur depend on the storage history 
of this RM-AV


(8) Problems/improvements occurred and solutions.

No problem occurred during this cruise.



REFERENCES

Aminot, A. and R. Kerouel (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 D.S. Kirkwood (1995): Report on the results of the fifth ICES 
    intercomparison exercise for nutrients in sea water, ICES coop. Res. Rep. 
    Set, 213.

Aminot, A. and R. Kerouel (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 T.M. Joyce (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, 9lpp, Tsukuba, Japan.

Aoyama, M., B. Susan, D. Minhan, D. Hideshi, I.G. Louis, H. Kasai, K. Roger, 
    K. Nurit, M. Doug, A. Murata, N. Nagai, H. Ogawa, H. Ota, H. Saito, K. 
    Saito, T. Shimizu, H. Takano, A. Tsuda, K. Yokouchi, and Y. Agnes (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, E.S. Braga, S.C. Coverly, 
    E. Czobik, I. Dahllof, M.H. Dai, G.O. Donnell, C. Engelke, G.C. Gong, 
    G.-H. Hong, D.J. Hydes, M.M. Jin, H. Kasai, R. Kerouel, Y. Kiyomono, M. 
    Knockaert, N. Kress, K.A. Krogslund, M. Kumagai, S. Leterme, Y. 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.

Gouretski, V.V. and K. Jancke (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., M. Ehrhardt, K. Kremling et al. (1983): Methods of seawater 
    analysis. 2nd rev. Weinheim: Verlag Chemie, Germany, West.

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

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

Kirkwood, D.S. (1992): Stability of solutions of nutrient salts during 
    storage. Mar. Chem., 38: 151-164.

Kirkwood, D.S., A. Aminot and M. Perttila (1991): Report on the results of 
    the ICES fourth intercomparison exercise for nutrients in sea water. ICES 
    coop. Res. Rep. Set, 174.

Mordy, C.W, M. Aoyama, L.I. Gordon, G.C. Johnson, R.M. Key, A.A. Ross, J.C. 
    Jennings and J. Wilson (2000): Deep water comparison studies of the 
    Pacific WOCE nutrient data set. Eos Trans-American Geophysical Union. 80 
    (supplement), 0S43.

Murphy, J. and J.P. Riley (1962): Analytica chim. Acta 27, 31-36. Uchida, H. 
    and M. Fukasawa (2005): WHP P6, A10, 13/14 REVISIT DATA BOOK Blue Earth 
    Global Expedition 2003 1, 2, (Aiwa Printing Co., Ltd., Tokyo).



3.5  CHLOROFLUOROCARBONS (CFCs)
     July 31, 2010


(1) Personnel

    Ken'ichi Sasaki     (MIO, JAMSTEC)
    Katsunori Sagishima (MWJ)
    Yuichi Sonoyama     (MWJ)
    Shoko Tatamisashi   (MWJ)
    Hideki Yamamoto     (MWJ)


(2) Introduction

Chlorofluorocarbons (CFCs) are completely man-made compounds that are 
chemically and biologically stable gasses in the environment. The CFCs have 
accumulated in the atmosphere since 1930's (Walker et al., 2000) and the 
atmospheric CFCs can slightly dissolve in sea surface water by air-sea gas 
exchange. The dissolved CFCs concentrations in sea surface water should have 
changed year by year and then penetrate into the ocean interior by water 
circulation. Three chemical species of CFCs, namely CFC-11 (CC13F), CFC-12 
(CC12F2) and CFC-113 (CPA), dissolved in seawater are useful as the transient 
tracers for the ocean circulation with times scale on the order of several 
decades. In these cruises, we determined concentrations of CFCs dissolved in 
seawater on board.


(3) Apparatus

Dissolved CFCs were measured by a typical method modified from the original 
design of Bullister and Weiss (1988). A developed purging and trapping system 
was attached to gas chromatograph (GC-14B: Shimadzu Ltd) having an electron 
capture detector (ECD-14: Shimadzu Ltd). Cold trap columns were "1/16 
stainless steel tubing packed with 5 cm of 100/120 mesh Porapak T. A 
pre-column and a main columns were Silica Plot capillary column [i.d.: 0.53 
mm, length: 8 m, film thickness: 6 gm] and a complex capillary column (Pola 
Bond-Q lid.: 0.53 mm, length: 7 m, film thickness: 10 gm] followed by Silica 
Plot Ii. d.: 0.53 mm, length: 22 m, film thickness: 6 gm]), respectively.



(4) Shipboard measurement


(4.1) Sampling

Before every CTD cast, the water sampler was cleaned by diluted acetone to 
remove any oils which could cause contaminations of CFCs. Seawater 
sub-samples were collected from 12 litter Niskin bottles into 250 ml glass 
bottles. The bottles had been filled with pure nitrogen gas before the 
sampling. The two times bottle volumes of seawater sample were overflowed. 
The bottles filled with seawater were kept in water bathes roughly controlled 
on the sample temperature. The CFC concentrations were determined within 12 
hrs.

In order to confirm CFC concentrations of standard gases and their 
stabilities and also to check CFC saturation levels in sea surface water with 
respect to overlying air, CFC mixing ratios in the background air were 
periodically analyzed. Air samples were continuously led into the 
Environmental Research Laboratory using 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 samples were collected from the 
flowing air into a 200 ml glass cylinder attached on the cock during running 
ship form a station to next station. Average mixing ratios of the atmospheric 
CFC-11, CFC-12 and CFC113 are 242.6 ± 6.3 ppt, 530.4 ± 7.6 ppt, and 76.2 ± 
5.4 ppt, respectively.


(4.2) Analysis

Constant volume of sample water (50 ml) was taken into the purging & trapping 
system. Dissolved CFCs were extracted by nitrogen gas purge. The sample gases 
were dried by magnesium perchlorate desiccant and concentrated on a trap 
column cooled to c -45°C. Following 8 minutes extraction, the trap column was 
isolated by valve switching and heated electrically to 140°C within 1.5 
minutes to desorb CFCs. The trap column was connected to GC and CFCs led into 
the pre-column. The gasses were roughly separated on the pre-column. When 
required compounds were eluted, the pre-column was switched onto cleaning 
line and flushed back by counter flow of pure nitrogen gas. The compounds 
which were sent onto main column were separated further and detected by an 
electron capture detector (ECD). Retention times of compounds were around 
1.5, 4.5 and 11.5 minutes for CFC-12, -11 and -113, respectively. Temperature 
of an analytical column and a detector was 95 and 240°C. Pure nitrogen gas 
(99.99995) was further purified by a molecular sieve 13X gas filter and was 
used for analyses. Mass flow rates of nitrogen gas were 10, 27, 20 and 120 
ml/min for carrier, detector make up, back flush and sample purging gasses, 
respectively. Gas loops whose volumes were 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 analysis using large loop (10 
ml) were performed more frequently to monitor change in the detector 
sensitivity. The standard gasses had been made by Japan Fine Products co. 
ltd. Standard gas cylinder numbers used in cruises were listed in Table 
3.5.1. Cylinder of CPB30524 was used as reference gas. Precise mixing ratios 
of the standard gasses were calculated by gravimetric data. The standard 
gases used in this cruise have not been calibrated to SIO scale standard 
gases yet because SIO scale standard gasses is hard to obtain due to legal 
difficulties for CFCs import into Japan. The data will be corrected as soon 
as possible when we obtain the standard gasses.



(5) Quality control


(5.1) Main problems on the shipboard analysis

A large and broad peak was interfered determining CFC-113 peak area for 
samples collected from surface layer (several hundred meters depth). 
Retention time of the interfering peak was around 3% shorter than that of 
CFC-113. The peak of compound interfering CFC-113 determination could not be 
completely separated from the peak of CFC-113 by our analytical condition. We 
tried to split these peaks on chromatogram analysis and give flag "4". In the 
case of the interfering peak completely covering the CFC-113 peak, we could 
not determine CFC-113 peak area and give flag "5".


(5.2) Blanks

CFCs concentrations in deep water which was one of oldest water masses in the 
ocean were low but not zero for CFC-11 and -12. Average concentrations of 
CFC-11, 12 in the deep water were 0.003 ± 0.001, 0.008 ± 0.001 pmol kg-1 (n= 
-1500), respectively. These values were assumed as sampling blanks which was 
contaminations from Niskin bottle and/or during sub-sampling and were 
subtracted from all data. Significant blank was not found in CFC-113 
measurements.


(5.3) Precisions

The analytical precisions were estimated from replicate sample analyses (610 
pairs for CFC-12, 609 pairs for CFC-11 and 401 pairs for CFC-113). The 
replicate samples were basically collected from two or three sampling depths 
which is around 100, 400 and 600 m depths in every stations. Precisions of 
CFCs are less than ± 0.010 pmol kg-1 or 0.6% for CFC-11 (whichever is 
greater), ± 0.006 pmol kg-1 or 0.8% for CFC-12 (whichever is greater), and ± 
0.010 pmol kg-1 for CFC-113, respectively.



REFERENCES

Bullister, J.L and R. E Weiss (1998): Determination of CC13F and CC12F2 in 
    seawater and air. Deep Sea Research, 35, 839-853.



Table 3.5.1: Standard gas cylinder list.
                 _________________________________________

                                CFC Concentrations (pptv).
                 Cylinder No.  ---------------------------
                                 CFC-11  CFC-12  CFC-113
                 ------------    ------  ------  -------
                 CPBO3O13         300     159     30.1
                 CPB19294         299     159     30.1
                 CPB28545         293     163     29.9
                 CPB30524         300     159     30.2
                 _________________________________________



3.6  DISSOLVED INORGANIC CARBON (CT)
     December 4, 2010


(1) Personnel

    Akihiko Murata   (RIGC/JAMSTEC)
    Minoru Kamata    (MWJ)
    Yoshiko Ishikawa (MWJ)
    Yasuhiro Arii    (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 (MR09-01, revisit of WOCE P21 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-A 
and -B; Nippon ANS, Inc.), which are slightly different from each other. The 
systems comprise of a seawater dispensing system, a CO2 extraction system and 
a coulometer (Model 5012, UIC Inc.).

The seawater dispensing system has an auto-sampler (6 ports), which takes 
seawater from a 300 ml borosilicate glass bottle and dispenses the seawater 
to a pipette of nominal 21 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 fit at the bottom of the stripping chamber. The 
CO2 stripped in the stripping chamber is carried by the nitrogen gas (140 ml 
min-1 for the systems A and B) to the coulometer through a dehydrating module. 
For the system A, the module consists of two electric dehumidifiers (kept at 
1 -2°C) and a chemical desiccant (Mg(ClO4)2). For the system B, it consists of 
three electric dehumidifiers with a chemical desiccant.



(4) Shipboard measurement


(4.1) Sampling

All seawater samples were collected from depth with 12 liter Niskin bottles 
basically at every other stations. The seawater samples for CT were taken with 
a plastic drawing tube (PFA tubing connected to silicone rubber tubing) into 
a 300 ml borosilicate glass bottle. The glass bottle was filled with seawater 
smoothly from the bottom following a rinse with a seawater of 2 full, bottle 
volumes. The glass bottle was closed by a stopper, which was fitted to the 
bottle mouth gravimetrically without additional force.

At a chemical laboratory on the ship, a headspace of approx. 1% of the bottle 
volume was made by removing seawater with a plastic pipette. A saturated 
mercuric chloride of 100 µl was added to poison seawater samples. The glass 
bottles were sealed with a greased (Apiezon M, M&I Materials Ltd) ground 
glass stopper and the clips were secured. The seawater samples were kept at 
4°C in a refrigerator until analysis. A few hours just before analysis, the 
seawater samples were kept at 20°C in a water bath.



(4.2) Analysis

At the start of each leg, we calibrated the measuring systems by blank and 5 
kinds of Na2CO3 solutions (nominally 500, 1000 1500, 2000, 2500 µmol kg-1). As 
it was empirically known that coulometers do not show a stable signal (low 
repeatability) with fresh (low absorption of carbon) coulometer solutions. 
Therefore we measured 2% CO2 gas repeatedly until the measurements became 
stable. Then we started the calibration.

The measurement sequence such as system blank (phosphoric acid blank), 2% CO2 
gas in a nitrogen base, seawater samples (6) was programmed to repeat. The 
measurement of 2% CO2 gas was made to monitor response of coulometer solutions 
(from UIC, Inc.). For every renewal of coulometer solutions, certified 
reference materials (CRMs, batch 92 and a small number of batch 79) provided 
by Prof. A.G. Dickson of Scripps Institution of Oceanography were analyzed. 
In addition, in-house reference materials (RM) (batch QRM Q20 and Q19 for 
systems A and B, 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 
(batches 92 and 79), 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 batches 92. We did use the measured results of batch 79 because of a 
small number of measurements.

Temporal variations of RM measurements for one coulometer solution are shown 
in Fig. 3.6.1. From this figure, it is evident that RM measurements had a 
linear trend of ~3 to ~7 µmol kg-1, implying that measurements of seawater 
samples also have the trend. The trend was also found in temporal changes of 
2% CO2 gas measurements. The trend seems to be due to "cell age" change 
(Johnson et al., 1998) of a coulometer solution.

Considering the trends, we adjusted measurements of seawater samples so as to 
be traceable to the certified value of batch 92.

Finally we surveyed vertical profiles of C1. In particular, we examined 
whether systematic differences between measurements of the systems A and B 
existed or not. Then taking other information of analyses into account, we 
determined a flag of each value of C1.

The average and standard deviation of absolute values of differences of CT 
analyzed consecutively were 0.8 and 0.7 µmol kg-1 (n=211), and 0.6 and 0.6 
µmol kg-1 (n= 165), for legs 1 and 2, respectively. The combined values were 
0.7 and 0.7 µmol kg-1 (n=376).



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.


Figure 3.6.1: Distributions of RM measurements as a function of sequential  
              day for Stns. 279 and 282 during MR09-01.



3.7  TOTAL ALKALINITY (AT)
     December 4, 2010


(1) Personnel

    Akihiko Murata   (RIGC/JAMSTEC)
    Tomonori Watai   (MWJ)
    Yoshiko Ishikawa (MWJ)
    Ayaka Hatsuyama  (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 (MR09-01, revisit of WOCE P21 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 
Bio, Varian), which are automatically controlled by a PC. The water 
dispensing unit has a water-jacketed pipette and a water-jacketed titration 
cell. The spectrophotometer has a water-jacketed quartz cell, length and 
volume of which are 8 cm and 13 ml, respectively. To circulate sample 
seawater between the titration and the quartz cells, PFA tubes are connected 
to the cells.

A seawater of approx. 42 ml is transferred from a sample bottle (borosilicate 
glass bottle; 130 ml) into the water-jacketed (25°C) pipette by pressurizing 
the sample bottle (nitrogen gas), and is introduced into the water-jacketed 
(25°C) 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 wavelengths (750, 616 and 444 nm). After 
the measurement, an acid titrant, which is a mixture of approx. 0.05 M HC1 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(T) = (-[H+](T)V(SA) + M(A)V(A))/V(S),

where M(A) 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 
V(S), V(A) and V(SA) 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(T)= -log[H+](T)= 4.2699+ 0.002578(35-S)+ 
              log((R-0.00131)/(2.3148-0.1299R))-log(1-0.001005S),

where S is the sample salinity, and R is the absorbance ratio calculated as:

                      R =(A(616)-A(750))/(A(444)-A(750)),

where Ai is the absorbance at wavelength i nm.  The HCl in the acid titrant 
was standardized (0.049983 M, 0.049982 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 92, certified value = 
2201.91 µmol kg-1, respectively) were also analyzed periodically to monitor 
systematic differences of measured A1 The reported values of AT were set to be 
traceable to the certified value of the batch 92.

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:

At the early stage of the 1st leg, we found malfunction of the instrument 
such as showing different AT values by different quantities of acid titrant 
added. The malfunction was attributed to the light source of 
spectrophotometer. After the light source was changed to a new one, the 
malfunction was resolved.



(5) Quality control

Temporal changes of AT, which originate from analytical problems, were 
monitored by measuring AT of CRM.

We found no abnormal measurements during the cruises.

After making the measured values of AT comparable to CRM, we examined vertical 
profiles of AT. Then taking other information of analyses into account, we 
determined a flag of each value of AT.

The average and standard deviation of absolute values of differences of AT 
analyzed consecutively were 0.5 and 0.5 µmol kg-1 (n = 200), and 0.6 and 0.5 
µmol kg-1 (n = 165) for legs 1 and 2, respectively. The combined values were 
calculated to be 0.5 and 0.5 µmol kg-1 (n = 365).



REFERENCE

Yao, W. and R. H. Byrne (1998): Simplified seawater alkalinity analysis: Use 
    of linear array spectrometers. Deep- Sea Research 145, 1383-1392.



3.8  pH (pH(T))
     December 10, 2010


(1) Personnel

    Akihiko Murata   (RIGC/JAMSTEC)
    Tomonori Watai   (MWJ)
    Yoshiko Ishikawa (MWJ)
    Ayaka Hatsuyama  (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 cruises (MR09-01, revisit of WOCE P21 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 same wavelengths.

The pH is calculated based on the following equation (Clayton and Byrne, 
1993):
                        ⎛     A(1)/A(2)-0.00691      ⎞
          pH= pK(2)+log ⎜ -------------------------- ⎟         (1),
                        ⎝ 2.2220 - 0.1331(A(1)/A(2)) ⎠   

where A1 and A2 indicate absorbances at 578 and 434 nm, respectively, and 
pK(2) is calculated as a function of water temperature and salinity.


(4) Shipboard measurement


(4.1) Sampling

All seawater samples were collected from depth with 12 liter Niskin bottles 
basically at every other stations. The seawater samples for pH were taken 
with a plastic drawing tube (PFA tubing connected to silicone rubber tubing) 
into a 300 ml borosilicate glass bottle, which was the same as used for CT 
sampling. The glass bottle was filled with seawater smoothly from the bottom 
following a rinse with a sea water of 2 full, bottle volumes. The glass 
bottle was closed by a stopper, which was fitted to the bottle mouth 
gravimetrically without additional force.

A few hours just before analysis, the seawater samples were kept at 25°C in a 
water bath.


(4.2) Analysis

For an indicator solution, m-cresol purple (2 mM) was used. The indicator 
solution was produced on board a ship, and retained in a 1000 ml DURAN® 
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 3.8.1 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 0.0005 and 0.0004 pH unit (n = 266), and 0.0004 
and 0.0004 pH unit (n = 205) for legs 1 and 2, respectively. The combined 
values were 0.0004 and 0.0004 pH unit (n = 471).



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 E.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. (unpublished manuscript).

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



3.9  LADCP
     November 1, 2010


(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 WHIM300 (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 rechargeable Ni-Cd battery pack. The LADCP unit was set for recording 
internally prior to each cast. After each cast the internally stored observed 
data was uploaded to the computer on-board. By combining the measured 
velocity of the sea water and bottom with respect to the instrument, and 
shipboard navigation data during the CTD cast, the absolute velocity profile 
can be obtained (e.g., Visbeck, 2002).

The instrument used in this cruise was as follows.
    Teledyne RD Instruments, WHIM300
        S/N 11853 (CPU firmware vet 50.32, vet 50.35, with pressure sensor) 
            S/N 8484 (CPU firmware vet 50.32, vet 50.35) 
            S/N 1512 (CPU firmware vet 50.35)


(3) Data collection

In this cruise, data were collected with the following configuration. 
    Bin size: 8 m 
    Number of bins: 14 
    Pings per ensemble: 1 
    Ping interval: 1 sec 
At the following stations, the CTD cast was carried out without the LADCP, 
because maximum pressure was beyond the pressure-proof of the LADCP (6000 m). 
Station P21-200


(4) Data collection problems

We changed the instruments many times due to various troubles. The log of 
changing instruments is as follows.

    Station P21-120: from S/N 11853 (firmware vet 50.32) to S/N 8484 
        (firmware vet 50.32) 
    Station P21-132: from S/N 8484 (firmware vet 50.32) to S/N 8484 
        (firmware vet 50.35)
    Station P21-141: from S/N 8484 (firmware vet 50.35) to S/N 11853 
        (firmware vet 50.35) 
    Station P21-174: from S/N 11853 (firmware vet 50.35) to S/N 1512 
        (firmware vet 50.35) 
    Station P21-181: from S/N 1512 (firmware vet 50.35) to S/N 11853 
        (firmware vet 50.35) 
    Station P21-182: from S/N 11853 (firmware vet 50.35) to S/N 1512 
        (firmware vet 50.35)

Until the Station 120, data recording was intermittently stopped during a 
cast due to the firmware (ver. 50.32) bug. Because the beam 2 of S/N 8484 
became weak at the Station 139, we changed instruments from 5/ N 8484 to S/N 
11853. The beam 2 of the instrument (S/N 11853) also didn't work well at the 
Station 173 and the instrument was changed to S/N 1512. Since the beam 3 of 
the instrument (S/N 1512) became weak at the Station 180, we tried the S/N 
11853 again at the Station 181 to compare the echo intensities. Since the 
instrument of S/N 1512 worked better than S/N 11853, the S/N 1512 was used 
after the Station 182 (see Fig. 3.9.1).


Figure 3.9.1: Cast-averaged echo intensities at 31 bin.



(4) Data process

Vertical profiles of velocity are obtained by the inversion method (Visbeck, 
2002). Since the first bin from LADCP is influenced by the turbulence 
generated by CTD frame, the weight for the inversion is set to 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 minutes 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.

However, the inversion method doesn't work well due to no-good velocity data 
due to the instrument problems as well as weak echo intensity at deep layers. 
So we added a cast flag for each profile. The flag of 5 means that data files 
for one cast were divided into small files due to firmware bugs provided form 
RDI. The flag of 6 means that 3 beam solutions were included in the cast.



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.


Water sample parameters:
       ______________________________________________________________

                                                        Mnemonic for
       Number  Parameter                     Mnemonic  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-l1       
          8    Freon-12                       CFC-12       
         12    14Carbon                       OELC14       C14ERR
         13    13Carbon                       OELC13       C13ERR
         23    Total carbon                   TCARBN       
         24    Total alkalinity               ALKALI       
         26    pH                             PH  
         27    Freon-113                      CFC113       
         28    Carbon Tetrachloride           CCL4  
         30    Ammonia                        NN4  
         31    Methane                        CH4  
         33    Nitrous oxide                  N2O  
         34    Chlorophyll a                  CHLORA       
         41    Particulate Organic Nitrogen   PON  
         42    Abundance of bacteria          BACT  
         47    Plutonium                      PLUTO        PLOTOER
         48    Primary Productivity    
         64    Incubation    
         82    15N-Nitrate                    15MO3  
         86    Flowcytometry    
         88    Nitrogen Fixation              DIAZO  
       ______________________________________________________________



REFERENCES

Aminot, A. and D.S. Kirkwood (1995): Report on the results of the fifth ICES 
    intercomparison exercise for nutrients in sea water, ICES coop. Res. Rep. 
    Set, 213.

Aminot, A. and R. Kerouel (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 R. Kerouel (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 T.M. Joyce (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, 9l pp, Tsukuba, Japan.

Aoyama, M., B. Susan, D. Minhan, D. Hideshi, I.G. Louis, H. Kasai, K. Roger, 
    K. Nurit, M. Doug, A. Murata, N. Nagai, H. Ogawa, H. Ota, H. Saito, K. 
    Saito, T. Shimizu, H. Takano, A. Tsuda, K. Yokouchi, and Y. Agnes (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, E.S. Braga, S.C. Coverly, 
    E. Czobik, I. Dahllof, M.H. Dai, G.O. Donnell, C. Engelke, G.C. Gong, 
    G.-H. Hong, D.J. Hydes, M.M. Jin, H. Kasai, R. Kerouel, Y. Kiyomono, M. 
    Knockaert, N. Kress, K.A. Krogslund, M. Kumagai, S. Leterme, Y. 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., T. Joyce, T. Kawano and Y. Takatsuki (2002): Standard seawater 
    comparison up to P129. Deep-Sea Research, I, Vol. 49, 1103-1114.

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

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 seawater; version 2. A.G. Dickson and C. 
    Goyet (eds), ORNL/CDIAC-74.

DOE (1994): Handbook of methods for the analysis of the various parameters of 
    the carbon dioxide system in sea water, version 2, A. G. Dickson & C. 
    Goyet, eds. (unpublished manuscript).

Downey, N.J., J.M. Stock, R.W. Clayton, and S.C. Cande (2007): History of the 
    Cretaceous Osbourn spreading center, J. Geophys. Res., 112, B04102, 
    doi:10.1029/2006JB004550.

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.

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

Goff, J.A., Y. Ma, A. Shah, J.R. Cochran, and J.-C. Sempere (1997): 
    Stochastic analysis of seafloor morphology on the flank of the Southeast 
    Indian Ridge: The influence of ridge morphology on the formation of 
    abyssal hills, J. Geophys. Res., 102, 15,521-15,534.

Gordon, L.I. and L.B. Jones (1973) The effect of temperature on carbon 
    dioxide partial pressure in seawater. Mar. Chem., 1, 317-322.

Gouretski, V.V. and K. Jancke (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., M. Ehrhardt, K. Kremling et al. (1983): Methods of seawater 
    analysis. 2nd rev. Weinheim: Verlag Chemie, Germany, West.

Johnson, K.M., A.G. Dickson, G. Eischeid, C. Goyet, P Guenther, R.M. Key, FJ. 
    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.

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

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.

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

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.

Kirkwood, D.S. (1992): Stability of solutions of nutrient salts during 
    storage. Mar. Chem., 38: 151-164.

Kirkwood, D.S., A. Aminot and M. Perttila (1991): Report on the results of 
    the ICES fourth intercomparison exercise for nutrients in sea water. ICES 
    coop. Res. Rep. Set, 174.

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.

Mackenzie, K.V. (1981): Nine-term equation for the sound speed in the oceans, 
    J. Acoust. Soc. Am., 70 (3), pp 807-812.

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.

Mordy, C.W, M. Aoyama, L.I. Gordon, G.C. Johnson, R.M. Key, A.A. Ross, J.C. 
    Jennings and J. Wilson (2000): Deep water comparison studies of the 
    Pacific WOCE nutrient data set. Eos Trans-American Geophysical Union. 80 
    (supplement), OS43.

Murphy, J. and J.P. Riley (1962): Analytica chim. Acta 27, 31-36.

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.

Nakanishi, M., K. Tamaki, and K. Kobayashi (1992): A new Mesozoic isochron 
    chart of the whole western Pacific Ocean: Paleomagnetic and tectonic 
    implications, Geophys. Res. Lett., 19, 693-696.

Sea-Bird Electronics (2009): SBE 43 dissolved oxygen (DO) sensor - hysteresis 
    corrections, Application note no. 64-3, 7 pp.

Searle, R. (1984): GLORIA survey of the East Pacific Rise Near 3.5°S: 
    Tectonic and volcanic characteristics of a fast spreading mid-ocean rise, 
    Tectonophysics, 101, 319-344.

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

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

Uchida, H. and M. Fukasawa (2005): WHP P6, Al0, 13/14 REVISIT DATA BOOK Blue 
    Earth Global Expedition 2003 1, 2, (Aiwa Printing Co., Ltd., Tokyo).

Uchida, H., K. Ohyama, S. Ozawa, and M. Fukasawa (2007): In situ calibration 
    of the Sea-Bird 9plus CTD thermometer, J. Atmos. Oceanic Technol., 24, 
    1961-1967.

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

Uchida, H., T. Kawano, I. Kaneko, and M. Fukasawa (2008): In situ calibration 
    of optode-based oxygen sensors, J. Atmos. Oceanic Technol., 25, 
    2271-2281.

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

Visbeck, M. (2002): Deep velocity profiling using Lowered Acoustic Doppler 
    Current Profilers: Bottom track and inverse solutions. J. Atmos. Oceanic 
    Technol., 19, 794-807.

Viso, R.F., R.L. Larson, and R.A. Pockalny (2005): Tectonic evolution of the 
    Pacific-Phoenix-Farallon triple junction in the South Pacific Ocean, 
    Earth Planet Sci. Lett., 233, 179-194.

Wetzel, R.G. and G.E. Likens (2000): Limnological Analysis, 429 pp., 
    Springer, New York, USA.



FIGURE CAPTIONS

Figure 1:  Station locations for WHP P21 revisit 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 1-hour and plotted every 1 degree in latitude or 
           longitude.

Figure 4:  Sea surface temperature (SST). Temperature data is averaged over 
           1-hour.

Figure 5   Sea surface salinity (SSS). Salinity data is averaged over 1-hour.

Figure 6   Difference in the partial pressure of CO2 between the ocean and the 
           atmosphere, ∆pCO2

Figure 7   Surface current at 100 m depth measured by ship board acoustic 
           Doppler current profiler (ADCP).

Figure 8:  Potential temperature (°C) cross section calculated by using CTD 
           temperature and salinity data calibrated by bottle salinity 
           measurements. Vertical exaggeration of the 0-6500 m section is 
           1000:1. Expanded section of the upper 1000 m is made with a 
           vertical exaggeration of 2500:1. 

Figure 9:  CTD salinity (psu) cross section calibrated by bottle salinity 
           measurements. Vertical exaggeration is same as Figure 8. 

Figure 10: Absolute salinity (g/kg) cross section calculated by using CTD 
           salinity data. Vertical exaggeration is same as Figure 8.

Figure 11: Density (σ0 ) (kg/m3) cross section calculated by using CTD 
           temperature and salinity data. Vertical exaggeration is same as 
           Figure 8.  

Figure 12: Same as Figure 11 but for σ4 (kg/m3).

Figure 13: Neutral density γn  (kg/m3) cross section calculated by using CTD 
           temperature and salinity data. Vertical exaggeration is same as 
           Figure 8.

Figure 14: Cross section of CTD oxygen (µmol/kg). Vertical exaggeration is 
           same as Figure 8.

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 8. 

Figure 16: Silicate (µmol/kg) cross section. Data with quality flags of 2 
           were plotted. Vertical exaggeration is same as Figure 8.

Figure 17: Nitrate (µmol/kg) cross section. Data with quality flags of 2 were 
           plotted. Vertical exaggeration is same as Figure 8. 

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 8.

Figure 19: Phosphate (µmol/kg) cross section.  Data with quality flags of 2 
           were plotted.  Vertical exaggeration is same as Figure 3. 

Figure 20: Dissolved inorganic carbon (µmol/kg) cross section. Data with 
           quality flags of 2 were plotted.  Vertical exaggeration is same as 
           Figure 8.

Figure 21: Total alkalinity (µmol/kg) cross section. Data with quality flags 
           of 2 were plotted. Vertical exaggeration is same as Figure 8.

Figure 22: pH cross section. Data with quality flags of 2 were plotted. 
           Vertical exaggeration is same as Figure 8.

Figure 23: CFC-11 (pmol/kg) cross section. Data with quality flags of 2 were 
           plotted. Vertical exaggeration is same as Figure 8.

Figure 24: CFC-12 (pmol/kg) cross section. Data with quality flags of 2 were 
           plotted. Vertical exaggeration is same as Figure 8.

Figure 25: CFC-113 (pmol/kg) cross section. Data with quality flags of 2 were 
           plotted. Vertical exaggeration is same as Figure 8.

Figure 26: Cross section of current velocity (cm/s) normal to the cruise 
           track measured by LADCP (northward is positive). 

Figure 27: Difference in potential temperature (°C) between results from WOCE 
           (from March to June 1994) and the revisit cruise (from April to 
           June 2009). 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 8.

Figure 28: Difference in salinity (psu) between results from WOCE and the 
           revisit cruise. Red and blue areas show areas where salinity 
           increased and decreased in the revisit cruise, respectively. CTD 
           salinity data with SSW batch correction1 were used. On white areas 
           differences in salinity do not exceed the detection limit of 0.002 
           psu. Vertical exaggeration is same as Figure 8.

Figure 29: Difference in dissolved oxygen (µmol/kg) between results from WOCE 
           and the revisit cruise. Red and blue areas show areas where 
           salinity increased and decreased in the revisit cruise, 
           respectively. CTD oxygen data were used. On white areas 
           differences in dissolved oxygen do not exceed the detection limit 
           of 2 µmol/kg. Vertical exaggeration is same as Figure 8.


Note

1. As for the traceability of SSW to Mantyla's value, the offset for the batches 
   P123 (WOCE P21) and P150 (the revisit cruise) are -0.0006 and -0.0005, 
   respectively (Kawano et al, 2006; T. Kawano, personal communication, 2009).



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

EVENT DATE  CONTACT          DATA TYPE          EVENT           SUMMARY 
----------  ---------------  -----------------  --------------  -------------------------
2010-05-27  Uchida, Hiroshi  CTD/SUM            Submitted       Data are public
            Exchange & WOCE files submitted/Public 

2010-08-12  Berys, Carolina  CTD/BTL/SUM        Website Update  added to "as received" 
            ArchiveHLY031bottledata.xls bottle file submitted by Jerry Kappa on 2010-03-
            24 and HLY031CTDO.zip CTD files submitted by Kelly Falkner on 2010-04-08 
            available under 'Preliminary/Unprocessed', unprocessed by CCHDO.

            49NZ20090410_wct_without_peru.zip CTD files in WOCE format, 
            49NZ20090410_ct1_without_peru.zip CTD files in Exchange format, and 
            49NZ20090410_sum_without_peru.txt station summary file submitted by Uchida 
            Hiroshi on 2010-05-27, and MR09-01_leg1-3_all.pdf cruise report submitted by 
            Jerry Kappa on 2010-08-12 available under 'Preliminary/Unprocessed', 
            unprocessed by CCHDO. 

2010-08-12  Fields, Justin   Cruise Report      Website Update  added to "as received" 

2011-09-19  Uchida, Hiroshi  BTL/Cruise Report  Submitted       Ready to go online 
55

