WFP Ref. No: PR01/P02
Last Updated: February 9, 1996

A.      Cruise Narrative

A.1     Highlights

A.1.a   WOCE designation:  PR01
                           PR02

A.1.b   EXPOCODE:          49RY9201_2
                           49RY9201_1 

A.1.c   Chief Scientist:   Michio Hirota,
                           Japan Meteorological Agency,
                           1-3-4, Otemachi, Chiyoda-ku,
                           Tokyo 100, Japan

A.1.d   Ship:              R/V Ryofu Maru 
        
A.1.e   Ports of call:     Leg 1: Tokyo, Japan to Marakal, Parau
                           Leg 2: Marakal, Parau to Naha, Japan 
                            
A.1.f   Cruise dates:      Leg 1: January 18, 1992 to February 5, 1992
                           Leg 2: February 10, 1992 to February 19, 1992
 

A.2     Cruise Summary Information

A.2.a   Geographic boundaries

A.2.b   Stations occupied

Observations of PR2 were carried out as part of the R/V Ryofu
Maru cruise RY9201 Leg 1, and those of PR1 were Leg 2.

Number of Stations

A total of 33 CTD/rosette stations for PR2 and 17 stations
for PR1 was occupied using a General Oceanics 12 bottle rosette
equipped with 12 1.7-liter Niskin water sample bottles, and an NBIS
MK III B CTD. No additional sensors were used with the CTD system.

Sampling

The following water sample measurements were made:
salinity, oxygen, nitrate, nitrite and phosphate on all stations. 
The depths sampled were: 10, 25, 50, 75, 100, 125, 150, 175, 200,
300, 400, 500, 600, 700, 800, 900, 1000, 1250, 1500, 2000, 2500,
3000, 4000 in meters on PR2. The samples were taken at shallower
depths than 1250m on PR1 except station RY8135. Surface water
samples were collected by a bucket at every station.

 
A.2.c   Floats and drifters deployed

A.2.d   Moorings deployed or recovered

 
A.3     List of Principal Investigators

The principal investigators responsible for each parameter
measured on the cruise are listed in Table 1. (All the
correspondence on these data should be addressed to the Director
of the Oceanographical Division, Marine Department, Japan
Meteorological Agency.)

Table 1.  Principal Investigators for all measurements.

          Name         Responsibility   Affiliation
          -----------------------------------------
          H. Minami    CTD, S           JMA/MD
          K. Fushimi   O2, Nutrients    JMA/MD
          -----------------------------------------
          JMA/MD  Marine Department, Japan Meteorological Agency


2.   Measurement Techniques and Calibrations

2.1  CTD

The CTD is NBIS Mark III B. An HP9000 Series 300 model 330
(Hewlette Packard) with 4 MByte of memory was used as the primary
data collection device and all FSK signals of CTD data were backed
up using the digital audio tape (DAT). The original sampling rate
is 31.25 samples per second, however, our software gets around 20
samples per second and compress these into one tenth of collected
data.

The temperature and pressure sensor were calibrated at the
calibration facility of SEA Co., Ltd. before the cruise. The
results are shown in Table 2.

Table 2.  CTD Calibration contents at laboratory

                    Temperature; linear fit
                    Time               Bias         Slope
Pre-Cruise (1 January 1992)         +0.2265      0.999888

                    Pressure(increase); linear fit
                    Time               Bias         Slope
Pre-Cruise (6 January 1992)         -1.7815      1.000931



The conductivity sensor was calibrated at sea using data
from the measurements of salinity collected at 15 stations on PR2
and 5 stations on PR1. The salinometer is Guildline Portasal model
8410 for the measurements of salinity of the water samples. We used
the batch P110 and P111 of IAPSO as standard sea water to calibrate
the salinometer. The calibration factor of conductivity sensor was
heavily depending on the pressure, we used the third-ordered
polynomial as function of pressure to correction as follows for PR2
and station RY8135 on PR1. The calibration function is determined
assuming that the bias zero. The results are shown in Table 3. We
lost the calibration value for RY8086-8118, so the table is left
as the blank.

                     C(correction)=Cf(P) x C(CTD)                (1)
                                 where
                  Cf(P)=A + B x P + C x P^2 + D x P^3            (2)


                      A             B             C            D
                                 (x10^-6)      (x10^-9)    (x10^-13)
   RY8086-8118                                                      
   RY8119-8134    0.99969             0.0           0.0          0.0
   RY8135         0.9994691     0.2852447     -.1210456    0.1114588

Table 3. The conductivity scaling factor


The temperature in "-.SEA" and "-.CTD" files are described
with the international temperature scale of 1990 (ITS-90).


2.2  Oxygen Measurements

The determination of dissolved oxygen was done by the
modified version of the Winkler method described in "Kaiyo Kansoku
Shishin (Manual on Oceanographic Observation)" published by the
Japan Meteorological Agency(1970). The reagent blank was not
subtracted. No estimation of accuracy and precision has been done.

Because no temperature data when samples were taken from
bottles are recorded, it was assumed that the density of samples
is 1022.156 kg/m3 (which assume the temperature for 28 degree C and
salinity for 34.68) and use this value to convert from umol/l to
umol/kg.


2.3  Nutrients Analyses

The nutrients analyses were done by the Technicon Auto
Analyzer II described in "Kaiyo Kansoku Shishin (Manual on
Oceanographic Observation)" published by the Japan Meteorological
Agency(1970). No estimation of accuracy and precision has been
done.

Because no temperature data while analyses are recorded,
it was assumed that the density of samples is 1022.156 kg/m3 (which
assume the temperature for 28 degree C and salinity for 34.68) and
use this value to convert from umol/l to umol/kg.


2.4   Noted for the -.SUM, -.SEA and -.CTD files

2.4.1 -.SUM

The positions of observation stations were recorded at the
beginning and end of the observation and these values were only
recorded in  minutes, we describe the averaged position as the
bottom (BO).

Since the surface water samples were taken by a stainless
steel water bucket, "Number of bottle" includes this bucket
sampling.

2.4.2 -.SEA

Our following parameters have the less precision than the
required, we describe the last digit of data as blank to meet the
data format: CTD temperature, CTD salinity, salinity, oxygen and
nitrates.

2.4.4 -.CTD

CTD temperature and salinity data have the less precision
than the required, we describe the last digit of data as blank to
meet the data format.

The number of samples averaged at the pressure level was
not available because our software was not recording the number of
data during data processing.


3. References

Japan Meteorological Agency, 1970: Kaiyo Kansoku Shishin (Manual
    on Oceanographic Observation). (in Japanese)

