John M. Morrison -- 20 December 1995 TN045: JGOFS Arabian Sea Process Study -- Process Cruise #2:
This "readme" file pertains to the CTD data taken during RV T.G. Thompson cruise TN045. This cruise was the second JGOFS Arabian Sea Process Leg and took place during March-April 1995. Dr. John Marra of the Lamont Doherty Earth Observatory 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. 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 CTD Calibration: On this cruise, one CTD configuration was used. The processing and calibration information for this configuration is given below: This the setup, processing and calibation information for the setup of all the CTD casts for cruise TN045. Sea-Bird Processing Information: Example from /jgofs/tn045/ctd/0400101.cnv * Sea-Bird SBE 9 Raw Data File: * FileName = G:\04500101.DAT * Software Version 4.205 * Temperature SN = 1605 * Conductivity SN = 1371 * Number of Bytes Per Scan = 37 * Number of Voltage Words = 4 * System UpLoad Time = Mar 14 1995 22:19:46 * NMEA Latitude = 22 23.05 N * NMEA Longitude = 059 53.02 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: Arabian Sea Process Study * TN045 # nquan = 15 # nvalues = 504 # 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 = depS: depth, salt water [m] # name 9 = potemp068: potential temperature, pri, IPTS-68 [deg C] # name 10 = sigma-t00: density, sigma-t [kg/m^3], T0, C0 # name 11 = sigma-é00: density, sigma-theta [kg/m^3], T0, C0 # name 12 = sal00: salinity, PSS-78 [PSU], T0, C0 # name 13 = sal11: salinity, PSS-78 [PSU], T1, C1 # name 14 = flag: 0.000e+00 # span 0 = 17.4367, 23.8239 # span 1 = 47.058937, 53.930725 # span 2 = 1.000, 253.000 # span 3 = 17.4439, 23.8246 # span 4 = 47.072361, 53.935005 # span 5 = -0.62334, 21.06996 # span 6 = 70.42, 104.03 # span 7 = 8.624e-02, 1.538e+00 # span 8 = 0.994, 251.264 # span 9 = 17.3938, 23.8224 # span 10 = 24.8994, 26.4857 # span 11 = 24.8998, 26.4962 # span 12 = 36.1074, 36.6021 # span 13 = 36.1074, 36.6048 # span 14 = 0.000e+00, 0.000e+00 # interval = decibars: 1 # start_time = Mar 14 1995 22:19:46 # bad_flag = -9.990e-29 # serial_numbers = t0:1605, c0:1371, pr:57657, t1:1316, c1:1084, ox:132, upoly0:Langdon, upoly1:Langdon, flS:75S, xmiss:156D # datcnv_date = Mar 14 1995 23:00:00, 4.205 # datcnv_in = 04500101.DAT CTD_24.CON 1605 1371 57657 # datcnv_skipover = 0 # wildedit_date = Mar 14 1995 23:02:34, 4.205 # wildedit_in = 04500101.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 # wildedit_excl_bad_scans = yes # celltm_date = Mar 14 1995 23:03:32, 4.205 # celltm_in = TEMP.CNV # celltm_alpha = 0.0300, 0.0000 # celltm_tau = 9.0000, 0.0000 # filter_date = Mar 14 1995 23:04:21, 4.205 # filter_in = 04500101.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 = Mar 14 1995 23:06:12, 4.205 # loopedit_in = TEMP.CNV # loopedit_minVelocity = 0.000 # loopedit_excl_bad_scans = yes # binavg_date = Mar 14 1995 23:07:19, 4.205 # binavg_in = 04500101.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 = Mar 14 1995 23:08:08, 4.205 # derive_in = TEMP.CNV CTD_24.CON # file_type = ascii *END* Calibration: Calibration for Conductivity and Salinity: MINIMUM DEPTH USED = 500.000 Conductivity STDEV= 0.00176471 MEAN= -0.00455533 Salinity STDEV= 0.00188188 MEAN= -0.00481573 If full range was used for the Conductivity and Salinity Calibration, the mean shifts slightly to -.0032, but the STDEV becomes 0.0117 as would be expected in the high-gradient, and variable surface layers. (This mean correction still falls within the standard deviation of the values below 500 meters.) Therefore, a correction of .005 was applied to the shipboard Conductivities and Salinities. The reported Conductivities and Salinities are good to +/- .002.