A.  Cruise narrative

1.  Highlights

Cruise designation:   RF15-07 (WHP-P04W revisit)
a.  EXPOCODE:         49UP20150724
b.  Chief scientist:  Keizo SHUTTA (shutta.kei@met.kishou.go.jp)
                      Marine Division
                      Global Environment and Marine Department
                      Japan Meteorological Agency (JMA)
                      1-3-4, Otemachi, Chiyoda-ku, Tokyo 100-8122, JAPAN
                      Phone:  +81-3-3212-8341 Ext. 4763
c.  Ship name:        R/V Ryofu Maru
d.  Ports of call:    Leg 1: Tokyo – Pohnpei, Leg 2: Pohnpei–Tokyo
e.  Cruise dates:     Leg 1: 24 July 2015–18 August 2015
                      Leg 2: 22 August 2015–15 September 2015
f.  Floats and drifters deployed:  2 Floats


1.  Cruise Summary Information

RF15-07 cruise was carried out during the period from July 24 to September 15, 2015. 
The cruise started from Japan, and sailed towards south east to the first station. 
Hydrographic observation started near Marshal Islands followed by sailing towards 
west along latitude approximately 10°N. This line was observed by Woods Hole 
Oceanographic Institution in 1989 as ‘WHP-P04’, which is a part of WOCE (World Ocean 
Circulation Experiment) Hydrographic Programme.

A total of 66 stations was occupied using a Sea-Bird Electronics (SBE) 36 position 
carousel equipped with 10-liter Niskin water sample bottles, a CTD system 
(SBE911plus) equipped with SBE35 deep ocean standards thermometer, JFE Advan
tech oxygen sensor (RINKO III), Teledyne Benthos altimeter (PSA-916D), and Teledyne 
RD Instruments L-ADCP (300kHz). To examine consistency of data, we carried out the 
observation twice at 9°30’N, 162°30’E (Stn.35 and 36). Cruise track and station 
location are shown in Figure 1.

At each station, full-depth CTDO2 (temperature, conductivity (salinity) and dissolved 
oxygen) profile and up to 36 water samples were taken and analyzed. Water samples 
were obtained from 10 dbar to approximately 10 m above the bottom. In addition, surface 
water was sampled using a stainless steel bucket at each station. Sampling layer 
is designed as so-called staggered mesh as shown in Table 1 (Swift, 2010). The bottle 
depth diagram is shown in Figure 2.

Water samples were analyzed for salinity, dissolved oxygen, nutrients, dissolved 
inorganic carbon (DIC), total alkalinity (TA), pH, CFC-11, CFC-12 and phytopigment 
(chlorophyll-a and phaeopigments). Underway measurements of partial pressure of 
carbon dioxide (pCO2), temperature, salinity, chlorophyll-a, subsurface current, 
bathymetry and meteorological parameters were conducted along the cruise track.

R/V Ryofu Maru departed Tokyo (Japan) on July 24, 2015. Before the observation at 
the first station, all watch standers were drilled in the method of sample drawing 
and CTD operations near Izu-Oshima (34°42’N, 139°51’E). The hydrographic cast of 
CTDO2 was started at the first station (Stn.66 (9°30’N, 178°48’E; RF5486)) on August 
2, 2015. Leg 1 consisted of 31 stations from Stn.66 to Stn.36 (9°30’N, 162°31’E; 
RF5516). She called for Pohnpei (Federated States of Micronesia) on August, 18 (Leg 
1). She left Pohnpei on August 22, 2015 for Tokyo (Japan) and arrived on September 
15, 2015 (Leg 2). Leg 2 consisted of 35 stations from Stn.35 (9°29’N, 162°29’E; 
RF5517) to Stn.1 (9°N, 137°E; RF5551). Location data of stations is shown in Table 2.

Two Argo floats were deployed along the cruise track. The information of deployed 
the floats are listed in Table 3.

Figure 1: Cruise track of RF15-07. 

Figure 2: The bottle depth diagram for WHP-P04 revisit. 


Table 1: The scheme of sampling layer in meters.

       9゜N (Stn.1 - Stn.66)                9゜N (Stn.1 - Stn.66)
—————————————————————————————————    —————————————————————————————————
Bottle  Scheme1  Scheme2  Scheme3    Bottle  Scheme1  Scheme2  Scheme3
count                                count  
——————  ———————  ———————  ———————    ——————  ———————  ———————  ———————
 1         10       10        10       21      1600     1670     1530
 2         25       25        25       22      1800     1870     1730
 3         50       50        50       23      2000     2070     1930
 4         75       75        75       24      2200     2270     2130
 5        100      100       100       25      2400     2470     2330
 6        125      125       125       26      2600     2670     2530
 7        150      150       150       27      2800     2870     2730
 8        175      175       175       28      3000     3080     2930
 9        200      200       200       29      3250     3330     3170
10        250      250       250       30      3500     3580     3420
11        300      330       280       31      3750     3830     3670
12        400      430       370       32      4000     4080     3920
13        500      530       470       33      4250     4330     4170
14        600      630       570       34      4500     4580     4420
15        700      730       670       35      4750     4830     4670
16        800      830       770       36      5000     5080     4920
17        900      930       870       37      5250     5330     5170
18       1000     1070       970       38      5500     5580     5420
19       1200     1270      1130       39      5750     5830     5670
20       1400     1470      1330       40      6000     6000     6000



Table 2: Station data of RF15-07 cruise. The ‘RF’ column indicates the JMA 
         station identification number.

Leg  Station    Position                 Leg  Station    Position
     Stn.  RF   Latitude   Longitude          Stn.  RF   Latitude    Longitude
———  —————————  —————————  ———————————   ———  —————————  ——————————  ———————————
 2     1  5551  8-59.51 N  136-59.79 E    1    36  5516   9-30.02 N  162-30.74 E
 2     2  5550  9-00.35 N  137-49.10 E    1    37  5515   9-29.80 N  163-20.14 E
 2     3  5549  8-59.33 N  138-11.38 E    1    38  5514  10-01.06 N  164-01.07 E
 2     4  5548  8-59.23 N  138-41.11 E    1    39  5513   9-30.66 N  163-59.35 E
 2     5  5547  8-59.36 N  139-35.34 E    1    40  5512   9-01.16 N  163-59.54 E
 2     6  5546  9-04.38 N  140-23.73 E    1    41  5511   7-59.93 N  163-58.52 E
 2     7  5545  9-07.51 N  141-13.56 E    1    42  5510   7-00.40 N  164-29.95 E
 2     8  5544  9-14.43 N  142-12.20 E    1    43  5509   6-01.10 N  165-00.94 E
 2     9  5543  9-17.02 N  142-51.00 E    1    44  5508   5-01.27 N  165-05.64 E
 2    10  5542  9-22.65 N  143-42.11 E    1    45  5507   5-00.67 N  165-40.86 E
 2    11  5541  9-27.78 N  144-30.22 E    1    46  5506   5-00.86 N  166-20.43 E
 2    12  5540  9-35.18 N  145-19.27 E    1    47  5505   5-00.73 N  167-01.30 E
 2    13  5539  9-31.20 N  145-50.19 E    1    48  5504   5-00.53 N  167-41.10 E
 2    14  5538  9-31.00 N  146-19.11 E    1    49  5503   5-00.01 N  168-20.87 E
 2    15  5537  9-30.88 N  147-00.57 E    1    50  5502   5-01.17 N  169-00.67 E
 2    16  5536  9-30.48 N  147-37.58 E    1    51  5501   5-00.69 N  169-30.60 E
 2    17  5535  9-35.25 N  148-05.82 E    1    52  5500   4-59.45 N  170-00.27 E
 2    18  5534  9-30.33 N  148-45.85 E    1    53  5499   5-00.96 N  170-40.84 E
 2    19  5533  9-33.77 N  149-20.78 E    1    54  5498   5-00.84 N  171-20.15 E
 2    20  5532  9-31.01 N  150-01.31 E    1    55  5497   4-59.86 N  172-00.93 E
 2    21  5531  9-30.61 N  150-51.12 E    1    56  5496   5-17.28 N  172-31.21 E
 2    22  5530  9-30.80 N  151-41.26 E    1    57  5495   5-34.83 N  173-00.08 E
 2    23  5529  9-30.04 N  152-29.82 E    1    58  5494   5-37.67 N  173-30.23 E
 2    24  5528  9-29.59 N  153-20.15 E    1    59  5493   6-12.87 N  174-10.65 E
 2    25  5527  9-29.59 N  154-10.33 E    1    60  5492   6-42.43 N  175-00.03 E
 2    26  5526  9-29.81 N  155-00.36 E    1    61  5491   7-10.53 N  175-49.42 E
 2    27  5525  9-29.74 N  155-51.13 E    1    62  5490   7-38.81 N  176-39.10 E
 2    28  5524  9-30.69 N  156-41.11 E    1    63  5489   8-04.76 N  177-29.13 E
 2    29  5523  9-30.28 N  157-30.43 E    1    64  5488   8-33.21 N  178-19.33 E
 2    30  5522  9-29.44 N  158-20.83 E    1    65  5487   8-59.18 N  178-58.44 E
 2    31  5521  9-30.38 N  159-10.14 E    1    66  5486   9-29.57 N  178-47.96 E
 2    32  5520  9-31.15 N  160-00.25 E               
 2    33  5519  9-25.17 N  160-50.30 E               
 2    34  5518  9-29.53 N  161-40.02 E              
 2    35  5517  9-29.05 N  162-29.27 E              



Table 3. Information of deployed float.

Float    Date and Time  Position of deployment
WMO      of deployment  ——————————————————————
number	      (UTC)      Latitude    Longitude    PI
———————  —————————————  ——————————  ———————————  ——————————————
5904990  2015 July 28   20-23.55 N  156-44.18 E  JAMSTEC  ARVOR
            10:59
2902959  2015 Sep. 9    24-58.68 N  138-42.79 E  JMA      APEX
            02:00
———————————————————————————————————————————————————————————————
ARVOR: nke Instrumentation (France)
APEX:  Teledyne Webb Research (USA)







List of Principal Investigators for all Measurements

The principal investigator (PI) and the person in charge responsible for major 
parameters measured on the cruise are listed in Table 4.


Table 4: List of principal investigators and the person in charge on the ship 
         for RF15-07.

Item                  Principal          Person in charge on the ship
                      Investigator (PI)
————————————————————  —————————————————  ————————————————————————————
Hydrography    
CTDO2 / LADCP         Toshiya NAKANO     Nobumi KATO
Salinity              Toshiya NAKANO     Koichi WADA
Dissolve oxygen       Toshiya NAKANO     Chihiro KAWAMURA
Nutrients             Toshiya NAKANO     Takahiro KITAGAWA
Phytopigment          Toshiya NAKANO     Takahiro KITAGAWA 
DIC                   Toshiya NAKANO     Shu SAITO
Total Alkalinity      Toshiya NAKANO     Shu SAITO
pH                    Toshiya NAKANO     Shu SAITO
CFCs                  Toshiya NAKANO     Kazutaka ENYO

Underway
Meteorology           Toshiya NAKANO     Keizo SHUTTA
Thermo-Salinograph    Toshiya NAKANO     Shu SAITO
pCO2                  Toshiya NAKANO     Shu SAITO
Chlorophyll-a         Toshiya NAKANO     Takahiro KITAGAWA
ADCP                  Toshiya NAKANO     Nobumi KATO
Bathymetry            Toshiya NAKANO     Nobumi KATO
     
Floats
Argo float (JMA)      Kazuhiro NEMOTO    Keizo SHUTTA
Argo float (JAMSTEC)  Shigeki HOSODA     Keizo SHUTTA



     Toshiya NAKANO (nakano_t@met.kishou.go.jp)
Marine Division, Global Environment and Marine Department, JMA
1-3-4, Otemachi, Chiyoda-ku, Tokyo 100-8122, JAPAN
Phone: +81-3-3212-8341 Ext. 5131
     
     Kazuhiro NEMOTO (k-nemoto@met.kishou.go.jp)
Marine Division, Global Environment and Marine Department, JMA
1-3-4, Otemachi, Chiyoda-ku, Tokyo 100-8122, JAPAN
Phone: +81-3-3212-8341 Ext. 5128

     Shigeki HOSODA (hosodas@jamstec.go.jp)
Ocean Circulation Research Group, 
Research and Development Center for Global Change (RCGC), 
Strategic Research and Development area, 
Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
2-15 Natsushima, Yokosuka-shi, Kanagawa 237-0061, JAPAN


Reference

Swift, J. H. (2010): Reference-quality water sample data: Notes on acquisition, 
record keeping, and evaluation. IOCCP Report No.14, ICPO Pub. 134, 2010 ver.1