John M. Morrison
29 January 1998
US JGOFS Antarctic Environments Southern Ocean Process Study (AESOPS)
NBP9604A: Ross Sea Process 1:
This "readme" file pertains to the CTD data taken
during RV N. B. Palmer cruise NBP9604A in October-November 1996.
Dr. W. O. Smith of the University of Tennessee was the
chief scientist during this leg (wosmith@utkux.utk.edu).
This cruise was the first process study leg
of the U.S. JGOFS program in the Southern Ocean (AESOPS).
CTD Calibration:
On this cruise, one CTD configuration was used. The processing
and calibration information for this configuration is given below.
The casts made with the Trace Metal Clean Rosette makde on this leg are not
reported here because this system was not designed to produce CTD data of
"WOCE" quality. The CTD system on this rosette was not capable of the
precision obtained from the system on the hydrographic rosette. It was
determined that the CTD dissolved oxygen sensor did not produce reliable
data on this cruise. The CTD transmissometer, fluorometer, light scattering
and PAR measurements are currently being calibrated by other investigators.
This is the setup, processing and calibration information for all of the CTD
casts made with the Primary CTD system for cruise NBP9604A.
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SEA-BIRD Processing Information: Example 96410101.CNV
* Sea-Bird SBE 9 Raw Data File:
* FileName = G:\96410101.DAT
* Software Version 4.218
* Temperature SN = 2168
* Conductivity SN = 1799
* Number of Bytes Per Scan = 30
* Number of Voltage Words = 4
* System UpLoad Time = Oct 08 1996 03:47:35
* NMEA Latitude = 63 27.58 S
* NMEA Longitude = 170 34.87 W
* NMEA UpLoad Time = not available
* Store Lat/Lon Data = Add to Header Only
** Ship: R/V Nathaniel B. Palmer
** Cruise: JGOFS Southern Ocean
# nquan = 19
# nvalues = 2481
# 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 = flC: fluorometer, chelsea
# name 8 = par: irradiance (PAR)
# name 8 = par: irradiance (PAR)
# name 9 = stLs6000: sea tech ls6000 [mg/l]
# name 10 = svC: sound velocity, chen millero [m/s]
# name 11 = depS: depth, salt water [m]
# name 12 = potemp068: potential temperature, pri, IPTS-68 [deg C]
# name 13 = sigma-t00: density, sigma-t [kg/m^3], T0, C0
# name 14 = sigma-é00: density, sigma-theta [kg/m^3], T0, C0
# name 15 = sal00: salinity, PSS-78 [PSU], T0, C0
# name 16 = sal11: salinity, PSS-78 [PSU], T1, C1
# name 17 = svC: sound velocity, chen millero [m/s]
# name 18 = flag: 0.000e+00
# span 0 = -1.7554, 2.1887
# span 1 = 26.741508, 30.879623
# span 2 = 4.000, 2484.000
# span 3 = -1.7579, 2.1890
# span 4 = 26.740807, 30.880001
# span 5 = 2.89509, 6.41725
# span 6 = 89.06, 90.87
# span 7 = -4.262e-03, 3.030e-01
# span 8 = 4.596e+01, 4.596e+01
# span 9 = 0.50083, 1.61392
# span 10 = 1439.53, 1493.55
# span 11 = 3.961, 2445.455
# span 12 = -1.7556, 2.1667
# span 13 = 27.2654, 27.8197
# span 14 = 27.2654, 27.8295
# span 15 = 33.8759, 34.7330
# span 16 = 33.8768, 34.7343
# span 17 = 1439.53, 1493.55
# span 18 = 0.000e+00, 0.000e+00
# interval = decibars: 1
# start_time = Oct 08 1996 03:47:35
# bad_flag = -9.990e-29
# sensor 0 = Frequency 0 temperature, primary, 2168, 30-Jul-96
# sensor 1 = Frequency 1 conductivity, primary, 1799, 26-Jul-96, cpcor = -9.5700e-08
# sensor 2 = Frequency 2 pressure, 43528, 14-Jun-91
# sensor 3 = Frequency 3 temperature, secondary, 2186, 30-Jul-96
# sensor 4 = Frequency 4 conductivity, secondary, 1798, 07-Aug-96, cpcor = -9.5700e-08
# sensor 5 = Extrnl Volt 0 oxygen, current, 0243, 11-Oct-95
# sensor 6 = Extrnl Volt 1 oxygen, temperature, 0243, 11-Oct-95
# sensor 7 = Extrnl Volt 2 transmissometer, 157D, 23-Feb-96
# sensor 8 = Extrnl Volt 3 fluorometer, chelsea, 88/2050-93, 23-Feb-96
# sensor 9 = Extrnl Volt 4 sea tech ls6000, 326, 05-17-96
# sensor 10 = Extrnl Volt 5 irradiance (PAR), 7175, 24-Feb-95
# datcnv_date = Oct 08 1996 05:51:04, 4.218
# datcnv_in = 96410101.DAT CTD_24.CON
# datcnv_skipover = 0
# wildedit_date = Oct 08 1996 05:52:45, 4.218
# wildedit_in = 96410101.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 flC par stLs6000 svC
# wildedit_excl_bad_scans = yes
# celltm_date = Oct 08 1996 05:53:21, 4.218
# celltm_in = 96410101.CNV
# celltm_alpha = 0.0300, 0.0000
# celltm_tau = 9.0000, 0.0000
# filter_date = Oct 08 1996 05:53:54, 4.218
# filter_in = 96410101.CNV
# filter_low_pass_tc_A = 0.150
# filter_low_pass_tc_B = 0.030
# filter_low_pass_A_vars = pr
# filter_low_pass_B_vars = c0mS/cm c1mS/cm
# loopedit_date = Oct 08 1996 05:55:07, 4.218
# loopedit_in = 96410101.CNV
# loopedit_minVelocity = 0.000
# loopedit_excl_bad_scans = yes
# binavg_date = Oct 08 1996 05:55:57, 4.218
# binavg_in = 96410101.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 = Oct 08 1996 05:56:35, 4.218
# derive_in = 96410101.CNV CTD_24.CON
# file_type = ascii
*END*
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Calibration:
Calibration for Conductivity and Salinity:
The CTD Conductivity sensor was calibrated by correlating the CTD
downcast conductivities with the conductivities of the water samples
taken with the SEA-BIRD carousel on the upcast. The mean and
standard deviations of these differences using all of the available
bottle data are given below. Only the salinities collected below
50 meters depth were used in this correlation. If the full range was used
the mean remains the same but the the STDEV becomes .003 as would be
expected for the high-gradient, variable surface layers. Subsets of
these data were also used to see if there was any significant
drift of the CTD sensors during the cruise. In this case none
was observed.
MINIMUM DEPTH USED = 50.0
Conductivity STDEV= 0.002 MEAN= -0.006
Salinity STDEV= 0.002 MEAN= -0.009
Therefore, a correction of .006 was applied to the CTD conductivities.
The reported Conductivities and Salinities are good to +/- .002.
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The Digital dissolved oxygen sensor did not provide reliable data
during this cruise. The CTD transmissometer, fluorometer, light
scattering and PAR measurements are currently being calibrated by
other investigators.
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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