File Format of BT data

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BT data files consist of header part (first 11 records) and data part, The following elements are separated by comma in each record.

(a) Header part
Record Information
Record No. Element
Rec-1 Ship name (listed in Table), cruise number and format code. Cruise number is identified with the year and the month. Format code is 'V2.1'.
Rec-2 Station number.Station number is given by the ship code (at the BT observation only. listed in Table) suffixed with three-digits consecutive numbers.
Rec-3 The number of data records.
Rec-4 Date(year/month/day) and time at the beginning of the bathythermograph(BT) observation in the Japan Standard Time (JST), which is nine hours ahead of the Coordinated Universal Time (UTC).
Rec-5 Latitude and longitude at the beginning of the bathythermograph (BT) observation with degrees, `-', minutes, `.', hundredth part of minutes.
Rec-6 Water depth at the beginning of the bathythermograph (BT) observation and sounding flag (listed in Table).
Rec-7 Corresponding station number of the subsurface current data and sub-station number.
Rec-8 Sea surface temperature and salinity.
Rec-9 Type of 'bathythermograph (BT) '; (X-BT: expendable BT, D-BT: Digital BT.).
Rec-10 for X-BT Probe type and probe serial number.
Rec-11 for X-BT Coefficients of the depth-time equation (listed in Table).
Rec-10, Rec-11 for D-BT Headers for data columns.
Rec-12, Rec-13 for X-BT Headers for data columns.


(b) Data part

Data are described at every 1 meter. The meaning of attached flags is shown in table.

Record information
Record No. Elements
below Rec-12 (Rec-14 for X-BT) Depth, Temperature and flag of temperature (listed in table).


Ship codes.
Ship Name CALL SIGN Ship Code BT Code AERO CODE
Kofu Maru JDWX KH th 1 2 47 002
Ryofu Maru JGQH RF tf 1 2 47 646
Keifu Maru JPBN KS ts 1 2 47 000
Chofu Maru JCCX NC tc 1 2 47 001
Seifu Maru JIVB SM tm 1 2 47 003

Probe code.
coefficients coefficients
Code Manufacturer Probe Type am bm
212 Turumi Seiki Co. T-6 6.691 -0.00225
222 Turumi Seiki Co. T-7 6.691 -0.00225
231 Turumi Seiki Co. T-5 6.828 -0.00182
252 Turumi Seiki Co. Deep Blue 6.691 -0.00225

Probe code and coefficients of the depth-time equation in Subsurface Temperature data. The depth-time equation is of the form;

zm = am * t + bm * t ^2

where zm is the depth and t is the elapsed time in seconds starting when the probe hits the surface; am and bm are positive constants.

Sounding flag of water depth in CTD, XCTD and BT data.
Flag No. Definition
1 Sounding by echo-sounder (not corrected)
2 Sounding by echo-sounder (corrected)
5 Water depth measured by CTD and altimeter
6 Water depth measured by BT or XCTD submersible
9 No sounding

Data flag in CTD, XCTD and BT data.
Flag No. Definition
2 Acceptable measurement.
3 Questionable measurement.
4 Bad measurement.
6 Interpolated over >2X10^4 Pa interval.
7 Despiked.
9 Not sampled.

Instrument codes for observation using expendable probe.
Code Instrument
32 Murayama Denki Z-60-16-III
33 Murayama Denki Z-60-16-II
45 Tsurumi Seiki Co. MK-100
46 Tsurumi Seiki Co. MK-130 Compatible recorder