John M. Morrison -- 8 July 1996
TN050: JGOFS Arabian Sea Process Study -- Process Cruise #5
This "readme" file pertains to the CTD data taken
during RV T.G. Thompson cruise TN050. This cruise was the
fifth JGOFS Arabian Sea Process Leg and took place during August -
September 1995. Prof. Sharon L. Smith of the University of Miami
(ssmith@rsmas.miami.edu) was the chief scientist.
Digital dissolved oxygen, transmissometer and fluoruometer data
were also collected on the CTD, but are not reported here
as we have not calibrated this data.
CTD Calibration:
On this cruise, one CTD configurations was used. The processing
and calibration information for this configuration is given as follows:
John M. Morrison 28 May 1996
This is the setup, processing and calibation information for
the CTD for cruise TN050.
Both the primary and secondary set of CTD sensors were calibrated
for this cruise. The calibrated data from the primary set of sensors
are used for the final data files, except for 4 stations where the
primary CTD sensors malfunctioned. This malfunction appeared to be
to a failure of the pump or something being trapped in the conductivity
cell of the primary sensor.
In addition, in both the primary and secondary sensors,
there was a trend in the differences between the CTD and
bottle salinities in the upper 500 meters of the data. Therefore,
the upper 500 meters were calibrated separately from the data below
500 meters.
Finally, a filter of +/-0.01 was applied to the differences between
CTD and Bottle salinities to remove large differences associated with
the salinity gradient region of the water column and not associated
with the calibration of the CTD sensors.
Both calibrations are given below, as well as a listing of stations
for which each calibration was used.
_________________________________________________________________________
Sea-Bird Processing Information: Example from 05000101.cnv
* Sea-Bird SBE 9 Raw Data File:
* FileName = G:\05000101.DAT
* Software Version 4.205
* Temperature SN = 1316
* Conductivity SN = 1371
* Number of Bytes Per Scan = 37
* Number of Voltage Words = 4
* System UpLoad Time = Aug 18 1995 14:22:07
* NMEA Latitude = 22 23.21 N
* NMEA Longitude = 059 52.99 E
* NMEA UpLoad Time = not available
* Store Lat/Lon Data = Add to Header and Append to Every Scan
* Ship: R/V Thomas G. Thompson
* Cruise: JGOFS Process 5
* TNO50
# nquan = 19
# nvalues = 803
# units = metric
# name 0 = t068: temperature, pri, IPTS-68 [deg C]
# name 1 = c0mS/cm: conductivity, primary [mS/cm]
# name 2 = pr: pressure [db]
# name 3 = t168: temperature, sec, IPTS-68 [deg C]
# name 4 = c1mS/cm: conductivity, secondary [mS/cm]
# name 5 = oxML/L: oxygen [ml/l]
# name 6 = xmiss: transmissometer
# name 7 = flS: fluorometer, sea tech
# name 8 = par: irradiance (PAR)
# name 9 = depS: depth, salt water [m]
# name 10 = potemp068: potential temperature, pri, IPTS-68 [deg C]
# name 11 = potemp168: potential temperature, sec, IPTS-68 [deg C]
# name 12 = sigma-é00: density, sigma-theta [kg/m^3], T0, C0
# name 13 = sigma-é11: density, sigma-theta [kg/m^3], T1, C1
# name 14 = sigma-t00: density, sigma-t [kg/m^3], T0, C0
# name 15 = sigma-t11: density, sigma-t [kg/m^3], T1, C1
# name 16 = sal00: salinity, PSS-78 [PSU], T0, C0
# name 17 = sal11: salinity, PSS-78 [PSU], T1, C1
# name 18 = flag: 0.000e+00
# span 0 = 13.5829, 22.6988
# span 1 = 42.632229, 51.934971
# span 2 = 2.000, 404.000
# span 3 = 13.5834, 22.6985
# span 4 = 42.632290, 51.933060
# span 5 = 0.01445, 3.13380
# span 6 = 73.98, 89.11
# span 7 = 1.951e-01, 4.408e+00
# span 8 = 4.287e+01, 4.287e+01
# span 9 = 1.987, 401.081
# span 10 = 13.5248, 22.6973
# span 11 = 13.5253, 22.6971
# span 12 = 24.7636, 26.9632
# span 13 = 24.7627, 26.9617
# span 14 = 24.7632, 26.9512
# span 15 = 24.7623, 26.9496
# span 16 = 35.8649, 35.9826
# span 17 = 35.8629, 35.9835
# span 18 = 0.000e+00, 0.000e+00
# interval = decibars: 1
# start_time = Aug 18 1995 14:22:07
# bad_flag = -9.990e-29
# serial_numbers = t0:1316, c0:1371, pr:34901, t1:1605, c1:1084,
ox:130229, flS:
84, xmiss:148D, obs:241, par:7176
# datcnv_date = Aug 18 1995 15:58:34, 4.205
# datcnv_in = 05000101.DAT CTD_24.CON 1316 1371 34901
# datcnv_skipover = 0
# wildedit_date = Aug 18 1995 16:01:34, 4.205
# wildedit_in = 05000101.CNV
# wildedit_pass1_nstd = 2.0
# wildedit_pass2_nstd = 20.0
# wildedit_npoint = 100
# wildedit_vars = t068 c0mS/cm pr t168 c1mS/cm oxML/L xmiss flS par
# wildedit_excl_bad_scans = yes
# celltm_date = Aug 18 1995 16:02:41, 4.205
# celltm_in = TEMP.CNV
# celltm_alpha = 0.0300, 0.0000
# celltm_tau = 9.0000, 0.0000
# filter_date = Aug 18 1995 16:03:37, 4.205
# filter_in = 05000101.CNV
# filter_low_pass_tc_A = 0.150
# filter_low_pass_tc_B = 0.100
# filter_low_pass_A_vars = pr
# filter_low_pass_B_vars =
# loopedit_date = Aug 18 1995 16:05:34, 4.205
# loopedit_in = TEMP.CNV
# loopedit_minVelocity = 0.000
# loopedit_excl_bad_scans = yes
# binavg_date = Aug 18 1995 16:06:54, 4.205
# binavg_in = 05000101.CNV
# binavg_bintype = Pressure Bins
# binavg_binsize = 1.00
# binavg_excl_bad_scans = yes
# binavg_downcast_only = no
# binavg_skipover = 0
# binavg_surface_bin = yes, min = 0.500, max = 0.500, value = 0.000
# derive_date = Aug 18 1995 16:07:55, 4.205
# derive_in = TEMP.CNV CTD_24.CON
# file_type = ascii
*END*
__________________________________________________________________________
Salinity Calibration:
CTD Salinity = Observed CTD Salinity - Sal Correction (Defined Below)
a. Salinity calibration for the Primary Sensors:
Stations:
/jgofs/tn050/ctd/05000101.cnf
/jgofs/tn050/ctd/05000102.cnf
/jgofs/tn050/ctd/05000202.cnf
/jgofs/tn050/ctd/05000203.cnf
/jgofs/tn050/ctd/05000204.cnf
/jgofs/tn050/ctd/05000301.cnf
/jgofs/tn050/ctd/05000302.cnf
/jgofs/tn050/ctd/05000303.cnf
/jgofs/tn050/ctd/05000401.cnf
/jgofs/tn050/ctd/05000402.cnf
/jgofs/tn050/ctd/05000403.cnf
/jgofs/tn050/ctd/05000501.cnf
/jgofs/tn050/ctd/05000502.cnf
/jgofs/tn050/ctd/05000503.cnf
/jgofs/tn050/ctd/05000601.cnf
/jgofs/tn050/ctd/05000602.cnf
/jgofs/tn050/ctd/05000603.cnf
/jgofs/tn050/ctd/05000701.cnf
/jgofs/tn050/ctd/05000702.cnf
/jgofs/tn050/ctd/05000703.cnf
/jgofs/tn050/ctd/05000704.cnf
/jgofs/tn050/ctd/05000706.cnf
/jgofs/tn050/ctd/05000707.cnf
/jgofs/tn050/ctd/05000709.cnf
/jgofs/tn050/ctd/05000710.cnf
/jgofs/tn050/ctd/05000711.cnf
/jgofs/tn050/ctd/05000712.cnf
/jgofs/tn050/ctd/05000713.cnf
/jgofs/tn050/ctd/05000714.cnf
/jgofs/tn050/ctd/05000715.cnf
/jgofs/tn050/ctd/05000801.cnf
/jgofs/tn050/ctd/05000802.cnf
/jgofs/tn050/ctd/05000901.cnf
/jgofs/tn050/ctd/05001001.cnf
/jgofs/tn050/ctd/05001101.cnf
/jgofs/tn050/ctd/05001102.cnf
/jgofs/tn050/ctd/05001103.cnf
/jgofs/tn050/ctd/05001201.cnf
/jgofs/tn050/ctd/05001202.cnf
/jgofs/tn050/ctd/05001203.cnf
/jgofs/tn050/ctd/05001301.cnf
/jgofs/tn050/ctd/05001302.cnf
/jgofs/tn050/ctd/05001304.cnf
/jgofs/tn050/ctd/05001305.cnf
/jgofs/tn050/ctd/05001309.cnf
/jgofs/tn050/ctd/05001310.cnf
/jgofs/tn050/ctd/05001311.cnf
/jgofs/tn050/ctd/05001312.cnf
/jgofs/tn050/ctd/05001313.cnf
/jgofs/tn050/ctd/05001314.cnf
/jgofs/tn050/ctd/05001401.cnf
/jgofs/tn050/ctd/05001402.cnf
/jgofs/tn050/ctd/05001403.cnf
/jgofs/tn050/ctd/05001501.cnf
/jgofs/tn050/ctd/05001502.cnf
/jgofs/tn050/ctd/05001701.cnf
/jgofs/tn050/ctd/05001705.cnf
/jgofs/tn050/ctd/05001708.cnf
/jgofs/tn050/ctd/05001709.cnf
/jgofs/tn050/ctd/05001710.cnf
/jgofs/tn050/ctd/05001711.cnf
/jgofs/tn050/ctd/05001712.cnf
/jgofs/tn050/ctd/05001714.cnf
/jgofs/tn050/ctd/05001901.cnf
/jgofs/tn050/ctd/05001902.cnf
/jgofs/tn050/ctd/05001903.cnf
/jgofs/tn050/ctd/05002001.cnf
/jgofs/tn050/ctd/05002002.cnf
/jgofs/tn050/ctd/05002101.cnf
/jgofs/tn050/ctd/05002102.cnf
/jgofs/tn050/ctd/05002104.cnf
/jgofs/tn050/ctd/05002105.cnf
/jgofs/tn050/ctd/05002109.cnf
/jgofs/tn050/ctd/05002110.cnf
/jgofs/tn050/ctd/05002111.cnf
/jgofs/tn050/ctd/05002112.cnf
/jgofs/tn050/ctd/05002113.cnf
/jgofs/tn050/ctd/05002201.cnf
/jgofs/tn050/ctd/05002202.cnf
/jgofs/tn050/ctd/05002301.cnf
/jgofs/tn050/ctd/05002302.cnf
/jgofs/tn050/ctd/05002401.cnf
/jgofs/tn050/ctd/05002403.cnf
/jgofs/tn050/ctd/05002404.cnf
/jgofs/tn050/ctd/05002408.cnf
/jgofs/tn050/ctd/05002409.cnf
/jgofs/tn050/ctd/05002410.cnf
/jgofs/tn050/ctd/05002411.cnf
/jgofs/tn050/ctd/05002412.cnf
/jgofs/tn050/ctd/05002413.cnf
/jgofs/tn050/ctd/05002501.cnf
/jgofs/tn050/ctd/05002502.cnf
/jgofs/tn050/ctd/05002601.cnf
/jgofs/tn050/ctd/05002602.cnf
/jgofs/tn050/ctd/05002604.cnf
/jgofs/tn050/ctd/05002605.cnf
/jgofs/tn050/ctd/05002609.cnf
/jgofs/tn050/ctd/05002610.cnf
/jgofs/tn050/ctd/05002611.cnf
/jgofs/tn050/ctd/05002612.cnf
/jgofs/tn050/ctd/05002613.cnf
/jgofs/tn050/ctd/05002701.cnf
/jgofs/tn050/ctd/05002801.cnf
/jgofs/tn050/ctd/05002901.cnf
/jgofs/tn050/ctd/05003001.cnf
______________________________________________________________________________
Shallow Correction:
MINIMUM PRESSURE (PR) USED = 0.
MAXIMUM PRESSURE USED = 499.
Sal Correction = 0.0045886859 - 1.5732105e-05 * CTD Pressure
Standard Deviation of Fit = .003
-------------------------------------------------------------------------------
Deep Correction:
MINIMUM PRESSURE USED = 500.
MAXIMUM PRESSURE USED = 4299.
Sal Correction = -0.0004
Standard Deviation of Fit = .001
------------------------------------------------------------------------------
Therefore in the upper 500 meters, the corrected CTD salinities are
good to +/- .003, while in the deep water the calibrated CTD
salinities are good to within +/- .001.
____________________________________________________________________________
b. Salinity calibration for the secondary sensor:
Stations:
/jgofs/tn050/ctd/05000201.cnf
/jgofs/tn050/ctd/05002504.cnf
/jgofs/tn050/ctd/05003002.cnf
/jgofs/tn050/ctd/05003101.cnf
______________________________________________________________________________
Shallow Correction:
MINIMUM PRESSURE (PR) USED = 0.
MAXIMUM PRESSURE USED = 499.
Sal Correction = 0.0030657103 -1.2614332e-05 * CTD Pressure
Standard Deviation of Fit = .003
-------------------------------------------------------------------------------
Deep Correction:
MINIMUM PRESSURE USED = 500.
MAXIMUM PRESSURE USED = 4299.
Sal Correction = -0.0034
Standard Deviation of Fit = .002
------------------------------------------------------------------------------
Therefore in the upper 500 meters, the corrected CTD salinities are
good to +/- .003, while in the deep water the calibrated CTD
salinities are good to within +/- .002.
The raw data files may be requested from:
DR.JOHN M. MORRISON
NORTH CAROLINA STATE UNIVERSITY
DEPARTMENT OF MARINE, EARTH AND ATMOSPHERIC SCIENCES
JORDAN HALL RM. 1125
BOX 8208
RALEIGH, NC 27695-8208
EMAIL: John_Morrison@NCSU.EDU
PHONE: 919-515-7449
FAX: 919-515-7802