prelininary data report
may 19, 1995
A.	Cruise Narrative
A.1.	Highlights

A.1.a	WOCE designation	PR19
A.1.b	EXPOCODE		Leg 3: 49TU9010/3
				Leg 4: 49TU9010/4

A.1.c	Chief Scientist		Leg 3: Ikuo Kaneko, NMO
               			Leg 4: Ikuo Kaneko, NMO

A.1.d	Ship			R/V Chofu Maru
A.1.e	Port of Call		Ishigaki
A.1.f	Cruise Dates		Leg 3: November 13 to November 16, 1990
              			Leg 4: November 18 to November 21, 1990


A.2	Cruise Summary
A.2.a	Geographic boundaries
A.2.b	Total number of stations occupied
A.2.c	Floats and drifters deployed
A.2.d	Moorings deployed or recovered

A.3	List of Principal Investigators

Table 1. Principal Investigators for All Measurements
---------------------------------------------------------
       Name           Responsibility      Affiliation
---------------------------------------------------------
      I. Kaneko        CTD, S              NMO
      M. Aoyama        O2,Nutrients        NMO
---------------------------------------------------------

A.4	Scientific Programme and Methods
    

R/V Chofu Maru sailed from Naha at 0600 UTC on 13 November
1990 for the leg 3 of the NC9010 cruise.  By 0800 UTC on 14
November the ship was at the first station of a section PR19.

A major problem on the DSF-6000 digital survey fathometer
braked the observation at the station IS-4, we launched the T-5
probes of the X-BT during the station from IS-4 to IS-2 and
course was set for Ishigaki to get the spare boards of the broken
fathometer. 
     
After receiving the spare boards  the ship sailed again at
0100 UTC on 18 November for NS-1, however, the fathometer did not
work well. Therefore we decided that the maximum depth of the CTD
lowering is up to 4000m to avoid the hard touch of the CTD to the
bottom of the sea. The observation from NS-1 to NS-7 were com-
pleted without incident. 

Course was set for Naze and rostered watches finished on 21
November 1990.

A.5	Major Problems and Goals Not Achieved

A.6	Other Incidents of Note

A.7	List of Cruise Participants

		Table 2. Cruise Participants
--------------------------------------------------------------
       Name           Responsibility      Affiliation
--------------------------------------------------------------
      I. Kaneko        Chief Scientist,       NMO
                       S,CTD Hardware,
                       CTD Software
      M. Aoyama        O2,Nutrients           NMO
      N. Ishikawa      Watch Stander          NMO
      H. Miyagi        O2,Nutrients           NMO 
      T. Tashiro       Watch Stander          NMO
      Y. Takatsuki     Watch Stander          NMO
      H. Kamiya        Watch Stander          NMO
      T. Shimizu       O2,Nutrients           NMO
      T. Tsutsumida    Watch stander          NMO
      K. Sakurai       Maritime Meteorology   NMO
-------------------------------------------------------------      

B.	Underway Measurements

B.1	Navigation and bathymetry
B.2	Acoustic Doppler Current Profiler (ADCP)
B.3	Thermosalinograph and underway dissolved oxygen, fluorometer, etc
B.4	XBT and XCTD
B.5	Meteorological observations
B.6	Atmospheric Chemistry

C.	Hydrographic measurements

The Neil Brown Mark III B CTD (6500 dbar sensor without
oxgen sensor) mounted in the 12 x 1.7 Liter General Oceanics
rosette multisampler frame was used for all of the vertical CTD
work.

In general at the CTD stations of which depth are shallower
than 100 meters and than 4000 meters, the package was lowered to
within 5 meters of the bottom and lowered to the depth of 95
percents of the bottom depth, respectively, because unable to use
the acoustic pinger on DSF-6000 fathometer. In addition due to
the problem on the fathometer, the package was lowered up to 4000
meters at the CTD stations deeper than 4000 meters depth.

The performance of the CTD and  multisampler was good
throughout the cruise.

A Hewlett Packard HP9000-320 with a 2 MByte of memory was
used as a primary data collection device and all CTD data was
backed up onto the audio tape. The original sampling rate is
31.25 samples per second, however, our software can get around 20
samples per second and compress it one tenth ( in case of 1600
dbar sensor, one sixth) of the collected data due to the limita-
tion of the memory. All of the CTD data of our observatory was
loaded on the basis of the compressed data described above. 

The results of the laboratory calibration for the tempera-
ture and pressure are shown in Table 3, however, these were not
used because the calibration methods for temperature and pressure
are not decided. 

Table 3. CTD calibration constants at laboratory
-------------------------------------------------------------------
          Temperature; linear fit

             Time             Bias        Slope

Pre -Cruise 15 Dec. 1989      0.0094701   0.9996821
Post-Cruise 12 Mar. 1991      0.0067286   0.9998651
 
          Pressure increasing (0-6000 dbar range); linear fit

             Time             Bias        Slope

Pre -Cruise 15 Dec. 1989      1.8902      1.000819
Post-Cruise 12 Mar. 1991      2.3260      1.000704

------------------------------------------------------------------

The conductivity scaling factor given in Table 4 is derived
from not a linear fit but a ratio of CTD data to water sample
data and were used for the final data load. The salinity determi-
nation of the water samples was with the Guildline AUTOSAL 8400A.
Standard Seawarter batch of P111 was used to standardize the
AUTOSAL. The precision of the salinity determination of the water
sample was 0.0005 PSS derived from the standard deviation of the
thirteen water samples collected from the same bottle.


Table 4. The conductivity scaling factor
----------------------------------------
Station No.         Bias      Slope
IS-13 - IS-5,         -       0.99976
NS-1  - NS-7          -       0.99976
---------------------------------------

                                       
 
3. Oxygen measurements
               
The determination of dissolved oxygen was done by the modi-
fied version of the Winkler method described in "Kaiyou kansoku
shishin (Manual of Oceanographic Observation)" published by the
Oceanographical Society of Japan (1970). The reagent blank was
not subtracted. The precision was generally better than 1 umol/l
at the concentration of surface level. No estimation of accuracy
has been made.

4. Nutrient analyses

The nutrients analyses were done by the Technicon Auto
Analyzer II described in "Kaiyou kansoku shishin (Manual of
Oceanographic Observation)" published by the Oceanographical
Society of Japan (1970). 

Sampling for nutrients followed for dissolved oxygen on
average 10-20 minutes after the casts were on deck. Samples were
drawn into 10 cm3 glass, narrow mouth, screw-capped bottles. Then
they were immediately introduced on the sampler tray of the
Technicon Auto Analyzer II for the analysis and generally the
analyses were begun within one hour after the casts were on deck.
if the delays were anticipated to be more than one hour, the
samples were refrigerated. Samples were refrigerated and stored
up to one hour on stations IS-13, IS-12, IS-10, IS-9, IS-6a, IS-
6, IS-5, NS-5, NS-6.  

The concentrations in umol/kg of oxygen, nitrate, nitrite
and phosphate were converted from the concentrations in umol/l
using the density calculated from the room temperature and salin-
ity of the water samples. The laboratory temperature for each
station are given in Table 5.

Table 5. Laboratory temperature for each station.
-----------------------------------------------------------
Station   Temp.     Station   Temp.     Station   Temp.
-----------------------------------------------------------
IS-13     27.       IS-12     27.       IS-11     26.
IS-10     25.       IS- 9     25.       IS- 8     25.
IS- 7'    25.       IS- 7     25.       IS- 6b    25.
IS- 6a    24.       IS- 6     24.       IS- 5     24.
NS- 1     23.       NS- 2     24.       NS- 3     24.
NS- 5     25.       NS- 6     26.       NS- 7     25.
------------------------------------------------------------
                                                      
5. Notes for the --.SUM,--.SEA and --.CTD files

The first 2 characters of the file name of --.SUM, --.SEA
and --.CTD files  are NC for R/V Chofu Maru of Nagasaki Marine
Observatory. These characters are followed by the last two digits
of year, the month and character R (R for PR18) or character S (S
for PR19) for the --.SUM and --.SEA files. In addition, the leg
of the cruise is appended in the file name of --.SEA files. For
the --.CTD files The characters NC are followed by the unique
station number and the cast number given in the Comments.

The file names of the --.SUM and --.SEA for this cruise are
as follows;

     NC9010S.SUM, 
     NC9010S3.SEA and NC9010S4.SEA


5.1 --.SUM

Since some of the time at the bottom (BO) and completion
(EN) of the cast, the positions at the beginning (BE), bottom
(BO) and the completion (EN) of the cast and the water depth of
station were not recorded, we leave the column of them blank. 

Since the surface water samplings were by a stainless steel 
water bucket, "Number of bottles" includes this bucket sampling.
  
The unique station numbers given by the Japan Meteorological
Agency with the cast numbers, which are used as the --.CTD files
name, are given in the "Comments".


5.2 --.SEA

We leave "the sample number (SAMPNO)" blank because the
sample numbers are different among the salinity, oxygen and
nutrients on our assignments.

Since the surface water samplings were by a stainless 
steel  water bucket, we leave the column of  "The   Bottle 
Number (BTLNBR)" at the surface layer blank. 

All water sample quality flags for the oxygen during  
this cruise were "3" because the precision did not exceed  
the WOCE standard of 0.1% and no estimation of accuracy    
has been made.

All water sample quality flags for the nutrients      
during this cruise were "3" because the no estimation of   
accuracy and precision has been made. 


5.3 --.CTD

The number of samples averaged at the pressure level, 
NUMBER, was the estimated value because original CTD data  
were lost in the processing described in "Section 2. CTD".

D.	Acknowledgments

E.	References

Oceanographical Society of Japan, 1970. Kaiyou kansoku     
shishin (Manual of Oceanographic Observation). Ed. by the  
Japan Meteorological Agency. (in Japanese)

Unesco, 1983. International Oceanographic tables. Unesco Technical Papers in 
Marine Science, No. 44.

Unesco, 1991. Processing of Oceanographic Station Data, 1991. By JPOTS
editorial panel.

F.	WHPO Summary


Several data files are associated with this report.  They are the tu9010.sum, 
tu9010.hyd, tu9010.csl and *.wct files.  The tu9010.sum file contains a summary
of the location, time, type of parameters sampled, and other pertient
information regarding each hydrographic station.  The tu9010.hyd file contains 
the bottle data. The *.wct files are the ctd data for each station.  The *.wct 
files are zipped into one file called tu9010.wct.zip. The tu9010.csl file is 
a listing of ctd and calculated values at standard levels.

The following is a description of how the standard levels and
calculated values were derived for the tu9010.csl file:

Salinity, Temperature and Pressure:  These three values were smoothed from
the individual CTD files over the N uniformly increasing pressure levels.
using the following binomial filter-

	t(j) = 0.25ti(j-1) + 0.5ti(j) + 0.25ti(j+1) j=2....N-1

When a pressure level is represented in the *.csl file that is not
contained within the ctd values, the value was linearly interpolated
to the desired level after applying the binomial filtering.   

Sigma-theta(SIG-TH:KG/M3), Sigma-2 (SIG-2: KG/M3), and Sigma-4(SIG-4:
KG/M3): These values are calculated using the practical salinity scale
(PSS-78) and the international equation of state for seawater (EOS-80)
as described in the Unesco publication 44 at reference pressures of the
surface for SIG-TH; 2000 dbars for Sigma-2; and 4000 dbars for Sigma-4.

Gradient Potential Temperature (GRD-PT: C/DB 10-3) is calculated as the
least squares slope between two levels, where the standard level is the
center of the interval.  The interval being the smallest of the two
differences between the standard level and the two closest values.
The slope is first determined using CTD temperature and then the
adiabatic lapse rate is subtracted to obtain the gradient potential
temperature.  Equations and Fortran routines are described in Unesco
publication 44.

Gradient Salinity (GRD-S: 1/DB 10-3) is calculated as the least squares
slope between two levels, where the standard level is the center of the
standard level and the two closes values.  Equations and Fortran
routines are described in Unesco publication 44.

Potential Vorticity (POT-V: 1/ms 10-11) is calculated as the vertical
component ignoring contributions due to relative vorticity, i.e.
pv=fN2/g, where f is the coriolius parameter, N is the bouyancy
frequency (data expressed as radius/sec), and g is the local
acceleration of gravity. 

Bouyancy Frequency (B-V: cph) is calculated using the adiabatic
leveling method, Fofonoff (1985) and Millard, Owens and Fofonoff
(1990).  Equations and Fortran routines are described in Unesco
publication 44.

Potential Energy (PE: J/M2: 10-5) and Dynamic Height (DYN-HT: M) are
calculated by integrating from 0 to the level of interest.  Equations and 
Fortran routines are described in Unesco publication, Processing of 
Oceanographic station data.

Neutral Density (GAMMA-N: KG/M3) is calculated with the program GAMMA-N
(Jackett and McDougall) version 1.3 Nov. 94.  

G.	Data Quality Evulation