CTD data collected during MOCNESS hauls from ARSV Laurence M. Gould, RVIB Nathaniel B. Palmer LMG0104, LMG0106, LMG0203, NBP0103, NBP0104, NBP0202, NBP0204 in the Southern Ocean from 2001-2002 (SOGLOBEC project)

Website: https://www.bco-dmo.org/dataset/2515
Version: final
Version Date: 2001-12-03

Project
» U.S. GLOBEC Southern Ocean (SOGLOBEC)

Program
» U.S. GLOBal ocean ECosystems dynamics (U.S. GLOBEC)
ContributorsAffiliationRole
Costa, Daniel P.University of California-San Diego (UCSD)Principal Investigator
Torres, Joseph J.University of South Florida (USF)Principal Investigator
Wiebe, Peter H.Woods Hole Oceanographic Institution (WHOI)Principal Investigator
Copley, NancyWoods Hole Oceanographic Institution (WHOI)Technician


Dataset Description

CTD observations taken simultaneously during MOCNESS tows,
plus MOCNESS sampling conditions

Note: Some variables have been eliminated from the display but are nevertheless available. These variables include: oxycurrent, oxytemp, tempco, and echo.

The MOCNESS is based on the Tucker Trawl principle (Tucker, 1951). The particular MOCNESS system from which these CTD data came is one of two net systems. The MOCNESS-1 has nine rectangular nets (1m x 1.4 m) which are opened and closed sequentially by commands through conducting cable from the surface (Wiebe et al., 1976). In both systems, "the underwater unit sends a data frame, comprised of temperature, depth, conductivity, net-frame angle, flow count, time, number of open net, and net opening/closing, to the deck unit in a compressed hexadecimal format every 2 seconds and from the deck unit to a microcomputer every 4 seconds... Temperature (to approximately 0.01 deg C) and conductivity are measured with SEABIRD sensors.
Normally, a modified T.S.K.-flowmeter is used... Both the temperature and conductivity sensors and the flow meter are mounted on top of the frame so that they face horizontally when the frame is at a towing angle of 45deg... Calculations of salinity (to approximately 0.01 o/oo S), potential temperature (theta), potential density (sigma), the oblique and vertical velocities of the net, and the approximate volume filtered by each net are made after each string of data has been received by the computer." (Wiebe et al., 1985)
In addition, data were collected from four other sensors attached to the frame: the Transmissometer, the Fluorometer, the Down welling light sensor, and the Oxygen sensor. A SeaBird underwater pump was also included in the sensor suite.

It should be noted that due to Antarctic cold, the first few minutes of data are often of questionable value as they are extremely variable and have a high frequency of "50.000" (indicating "bad values") in the temp, theta and sal fields. Once the sensors encounter deeper, warmer water, they start recording good values.

For additional information, contact the chief scientist for the cruise.

 

References

Fofonoff and Millard, 1983, UNESCO technical papers in Marine Sciences, #44

Tucker, G.H., 1951. Relation of fishes and other organisms to the scattering of underwater sound. Journal of Marine Research, 10: 215-238.

Wiebe, P.H., K.H. Burt, S. H. Boyd, A.W. Morton, 1976. The multiple opening/closing net and environmental sensing system for sampling zooplankton. Journal of Marine Research, 34(3): 313-326

Wiebe, P.H., A.W. Morton, A.M. Bradley, R.H. Backus, J.E. Craddock, V. Barber, T.J. Cowles and G.R. Flierl, 1985. New developments in the MOCNESS, an apparatus for sampling zooplankton and micronekton. Marine Biology, 87: 313-323.

last updated January 10, 2006; gfh


Methods & Sampling

The MOCNESS is based on the Tucker Trawl principle (Tucker, 1951). The particular MOCNESS system from which these CTD data came is one of two net systems. The MOCNESS-1 has nine rectangular nets (1m x 1.4 m) which are opened and closed sequentially by commands through conducting cable from the surface (Wiebe et al., 1976). The MOCNESS-10 (with 10 m2 nets)carries 6 nets of 3.0-mm circular mesh. In both systems, 'the underwater unit sends a data frame, comprised of temperature, depth, conductivity, net-frame angle, flow count, time, number of open net, and net opening/closing, to the deck unit in a compressed hexadecimal format every 2 seconds and from the deck unit to a microcomputer every 4 seconds... Temperature (to approximately 0.01 deg C) and conductivity are measured with SEABIRD sensors. Normally, a modified T.S.K.-flowmeter is used... Both the temperature and conductivity sensors and the flow meter are mounted on top of the frame so that they face horizontally when the frame is at a towing angle of 45deg... Calculations of salinity (to approximately 0.01 o/oo S), potential temperature (theta), potential density (sigma), the oblique and vertical velocities of the net, and the approximate volume filtered by each net are made after each string of data has been received by the computer.' (Wiebe et al., 1985) In addition, data were collected from four other sensors attached to the frame: the Transmissometer, the Fluorometer, the Down welling light sensor, and the Oxygen sensor. A SeaBird underwater pump was also included in the sensor suite.


Data Processing Description

It should be noted that due to Antarctic cold, the first few minutes of data are often of questionable value as they are extremely variable and have a high frequency of '50.000' (indicating 'bad values') in the temp, theta and sal fields. Once the sensors encounter deeper, warmer water, they start recording good values.

For additional information, contact the chief scientist for the cruise.


[ table of contents | back to top ]

Data Files

File
mocness_ctd.csv
(Comma Separated Values (.csv), 35.95 MB)
MD5:dff00f9e9c27ef6719520efb67eb25fe
Primary data file for dataset ID 2515
mocness_ctd_LMG0104.csv
(Comma Separated Values (.csv), 4.45 MB)
MD5:20bc1e5885e9112e83e3c19976e8dbbc
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level1.pl, V2.07so/October 3, 2001
For MOC1 data, with filetype=pro
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level2.pl, V2.13so/May 17, 2004
For /data12/sodata/lmg0104/moc, MOC1, pro, LMG0104, 2001
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level3.pl, V1.51/January 28, 2000
Using data file /data12/sodata/lmg0104/moc/M01_01.PRO
Tow: M-01-001 LMG0104
Date: 01 May 2001
Temperature Probe # 2686 Conductivity Probe # 2250
Pressure Probe # 149 Oxygen Probe # 1
Transmissometer # 439 Fluorometer # 1
mocness_ctd_LMG0106.csv
(Comma Separated Values (.csv), 1.52 MB)
MD5:12403c102a68ddfc6875d520806e7a99
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level1.pl, V2.07so/October 3, 2001
For MOC1 data, with filetype=pro
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level2.pl, V2.13so/May 17, 2004
For /data12/sodata/lmg0104/moc, MOC1, pro, LMG0104, 2001
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level3.pl, V1.51/January 28, 2000
Using data file /data12/sodata/lmg0104/moc/M01_01.PRO
Tow: M-01-001 LMG0104
Date: 01 May 2001
Temperature Probe # 2686 Conductivity Probe # 2250
Pressure Probe # 149 Oxygen Probe # 1
Transmissometer # 439 Fluorometer # 1
mocness_ctd_LMG0203.csv
(Comma Separated Values (.csv), 4.76 MB)
MD5:a6121a1a84d32d872daae3882085c5f0
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level1.pl, V2.07so/October 3, 2001
For MOC1 data, with filetype=pro
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level2.pl, V2.13so/May 17, 2004
For /data12/sodata/lmg0104/moc, MOC1, pro, LMG0104, 2001
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level3.pl, V1.51/January 28, 2000
Using data file /data12/sodata/lmg0104/moc/M01_01.PRO
Tow: M-01-001 LMG0104
Date: 01 May 2001
Temperature Probe # 2686 Conductivity Probe # 2250
Pressure Probe # 149 Oxygen Probe # 1
Transmissometer # 439 Fluorometer # 1
mocness_ctd_NBP0103.csv
(Comma Separated Values (.csv), 7.19 MB)
MD5:e583ccf0915ecf824ad8e7c173c7abb7
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level1.pl, V2.07so/October 3, 2001
For MOC1 data, with filetype=pro
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level2.pl, V2.13so/May 17, 2004
For /data12/sodata/lmg0104/moc, MOC1, pro, LMG0104, 2001
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level3.pl, V1.51/January 28, 2000
Using data file /data12/sodata/lmg0104/moc/M01_01.PRO
Tow: M-01-001 LMG0104
Date: 01 May 2001
Temperature Probe # 2686 Conductivity Probe # 2250
Pressure Probe # 149 Oxygen Probe # 1
Transmissometer # 439 Fluorometer # 1
mocness_ctd_NBP0104.csv
(Comma Separated Values (.csv), 4.40 MB)
MD5:d0c9483286a2f563736a68a69ca1e149
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level1.pl, V2.07so/October 3, 2001
For MOC1 data, with filetype=pro
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level2.pl, V2.13so/May 17, 2004
For /data12/sodata/lmg0104/moc, MOC1, pro, LMG0104, 2001
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level3.pl, V1.51/January 28, 2000
Using data file /data12/sodata/lmg0104/moc/M01_01.PRO
Tow: M-01-001 LMG0104
Date: 01 May 2001
Temperature Probe # 2686 Conductivity Probe # 2250
Pressure Probe # 149 Oxygen Probe # 1
Transmissometer # 439 Fluorometer # 1
mocness_ctd_NBP0202.csv
(Comma Separated Values (.csv), 7.87 MB)
MD5:33321a3a3244739f64988e801e9f9928
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level1.pl, V2.07so/October 3, 2001
For MOC1 data, with filetype=pro
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level2.pl, V2.13so/May 17, 2004
For /data12/sodata/lmg0104/moc, MOC1, pro, LMG0104, 2001
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level3.pl, V1.51/January 28, 2000
Using data file /data12/sodata/lmg0104/moc/M01_01.PRO
Tow: M-01-001 LMG0104
Date: 01 May 2001
Temperature Probe # 2686 Conductivity Probe # 2250
Pressure Probe # 149 Oxygen Probe # 1
Transmissometer # 439 Fluorometer # 1
mocness_ctd_NBP0204.csv
(Comma Separated Values (.csv), 5.77 MB)
MD5:92c6d581f355eb998af3070ca859179e
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level1.pl, V2.07so/October 3, 2001
For MOC1 data, with filetype=pro
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level2.pl, V2.13so/May 17, 2004
For /data12/sodata/lmg0104/moc, MOC1, pro, LMG0104, 2001
Displayed by /data/rgroman/ctd_so_mocness/mocpro_level3.pl, V1.51/January 28, 2000
Using data file /data12/sodata/lmg0104/moc/M01_01.PRO
Tow: M-01-001 LMG0104
Date: 01 May 2001
Temperature Probe # 2686 Conductivity Probe # 2250
Pressure Probe # 149 Oxygen Probe # 1
Transmissometer # 439 Fluorometer # 1

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Parameters

ParameterDescriptionUnits
cruiseid

cruise identification, e.g. NBP0202, for RVIB Palmer cruise 0202

temp

temperature of water

degrees C
datatype

sampling method - instrument type, e.g. MOCNESS-1 or MOCNESS-10

year

year

brief_desc

brief cruise description, such as process or mooring

tow

tow number

day_gmt

day of month, GMT, 1-31

month_gmt

month of year, GMT, 1 - 12

station

station number, from event log

station_std

standard station number, from event log

yrday_gmt

year day as a decimal, based on Julian calendar, GMT

YYY.Y
time_gmt

time, GMT using 24 hour clock to decimal minutes

HHmm.m
press

depth of observation or sample

meters
potemp

potential temperature or theta1 ¹Fofonoff and Millard, 1983, UNESCO technical papers in Marine Sciences, #44

sal

salinity calculated from conductivity, bad values are set to 50

sigma_0

potential density1

¹Fofonoff and Millard, 1983, UNESCO technical papers in Marine Sciences, #44

flvolt

relative fluorescence (0-5 volts)

volts
angle

angle of net frame relative to vertical (0-89 degrees)

degrees
flow

consecutive flow counts

hzvel

horizontal net velocity

m/min
vtvel

vertical net velocity

m/min
vol_filt

volume filtered

meters<sup>3</sup>
trans_v

transmissometry or light transmission, (0-5 volts)

volts
o2

dissolved oxygen

ml/liter
lite

downwelling light

volts
net

MOCNESS net number, (00-08)

lat

latitude, negative = South

DD.D
lon

longitude, negative = West

DDD.D


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Instruments

Dataset-specific Instrument Name
Conductivity, Temperature, Depth
Generic Instrument Name
CTD - profiler
Generic Instrument Description
The Conductivity, Temperature, Depth (CTD) unit is an integrated instrument package designed to measure the conductivity, temperature, and pressure (depth) of the water column. The instrument is lowered via cable through the water column. It permits scientists to observe the physical properties in real-time via a conducting cable, which is typically connected to a CTD to a deck unit and computer on a ship. The CTD is often configured with additional optional sensors including fluorometers, transmissometers and/or radiometers. It is often combined with a Rosette of water sampling bottles (e.g. Niskin, GO-FLO) for collecting discrete water samples during the cast. This term applies to profiling CTDs. For fixed CTDs, see https://www.bco-dmo.org/instrument/869934.

Dataset-specific Instrument Name
CTD MOCNESS
Generic Instrument Name
CTD MOCNESS
Generic Instrument Description
The CTD part of the MOCNESS includes 1) a pressure (depth) sensor which is a thermally isolated titanium strain gauge with a standard range of 0-5000 decibars full scale, 2) A Sea Bird temperature sensor whose frequency output is measured and sent to the surface for logging and conversion to temperature by the software in the MOCNESS computer (The system allows better than 1 milli-degree resolution at 10 Hz sampling rate), and 3) A Sea Bird conductivity sensor whose output frequency is measured and sent to the surface for logging and conversion to conductivity by the software in the computer (The system allows better than 1 micro mho/cm at 10 Hz sampling rate). The data rate depends on the speed of the computer and the quality of the cable. With a good cable, the system can operate at 2400 baud, sampling all variables at 2 times per second. One sample every 4 seconds is the default, although the hardware can operate much faster. (From The MOCNESS Manual)


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Deployments

LMG0104

Website
Platform
ARSV Laurence M. Gould
Report
Start Date
2001-04-20
End Date
2001-06-05
Description
Methods & Sampling
The MOCNESS is based on the Tucker Trawl principle (Tucker, 1951). The particular MOCNESS system from which these CTD data came is one of two net systems. The MOCNESS-1 has nine rectangular nets (1m x 1.4 m) which are opened and closed sequentially by commands through conducting cable from the surface (Wiebe et al., 1976). The MOCNESS-10 (with 10 m2 nets)carries 6 nets of 3.0-mm circular mesh. In both systems, 'the underwater unit sends a data frame, comprised of temperature, depth, conductivity, net-frame angle, flow count, time, number of open net, and net opening/closing, to the deck unit in a compressed hexadecimal format every 2 seconds and from the deck unit to a microcomputer every 4 seconds... Temperature (to approximately 0.01 deg C) and conductivity are measured with SEABIRD sensors. Normally, a modified T.S.K.-flowmeter is used... Both the temperature and conductivity sensors and the flow meter are mounted on top of the frame so that they face horizontally when the frame is at a towing angle of 45deg... Calculations of salinity (to approximately 0.01 o/oo S), potential temperature (theta), potential density (sigma), the oblique and vertical velocities of the net, and the approximate volume filtered by each net are made after each string of data has been received by the computer.' (Wiebe et al., 1985) In addition, data were collected from four other sensors attached to the frame: the Transmissometer, the Fluorometer, the Down welling light sensor, and the Oxygen sensor. A SeaBird underwater pump was also included in the sensor suite.

Processing Description
It should be noted that due to Antarctic cold, the first few minutes of data are often of questionable value as they are extremely variable and have a high frequency of '50.000' (indicating 'bad values') in the temp, theta and sal fields. Once the sensors encounter deeper, warmer water, they start recording good values. For additional information, contact the chief scientist for the cruise.

LMG0106

Website
Platform
ARSV Laurence M. Gould
Report
Start Date
2001-07-21
End Date
2001-09-01
Description
Methods & Sampling
The MOCNESS is based on the Tucker Trawl principle (Tucker, 1951). The particular MOCNESS system from which these CTD data came is one of two net systems. The MOCNESS-1 has nine rectangular nets (1m x 1.4 m) which are opened and closed sequentially by commands through conducting cable from the surface (Wiebe et al., 1976). The MOCNESS-10 (with 10 m2 nets)carries 6 nets of 3.0-mm circular mesh. In both systems, 'the underwater unit sends a data frame, comprised of temperature, depth, conductivity, net-frame angle, flow count, time, number of open net, and net opening/closing, to the deck unit in a compressed hexadecimal format every 2 seconds and from the deck unit to a microcomputer every 4 seconds... Temperature (to approximately 0.01 deg C) and conductivity are measured with SEABIRD sensors. Normally, a modified T.S.K.-flowmeter is used... Both the temperature and conductivity sensors and the flow meter are mounted on top of the frame so that they face horizontally when the frame is at a towing angle of 45deg... Calculations of salinity (to approximately 0.01 o/oo S), potential temperature (theta), potential density (sigma), the oblique and vertical velocities of the net, and the approximate volume filtered by each net are made after each string of data has been received by the computer.' (Wiebe et al., 1985) In addition, data were collected from four other sensors attached to the frame: the Transmissometer, the Fluorometer, the Down welling light sensor, and the Oxygen sensor. A SeaBird underwater pump was also included in the sensor suite.

Processing Description
It should be noted that due to Antarctic cold, the first few minutes of data are often of questionable value as they are extremely variable and have a high frequency of '50.000' (indicating 'bad values') in the temp, theta and sal fields. Once the sensors encounter deeper, warmer water, they start recording good values. For additional information, contact the chief scientist for the cruise.

LMG0203

Website
Platform
ARSV Laurence M. Gould
Report
Start Date
2002-04-07
End Date
2002-05-20
Description
Methods & Sampling
The MOCNESS is based on the Tucker Trawl principle (Tucker, 1951). The particular MOCNESS system from which these CTD data came is one of two net systems. The MOCNESS-1 has nine rectangular nets (1m x 1.4 m) which are opened and closed sequentially by commands through conducting cable from the surface (Wiebe et al., 1976). The MOCNESS-10 (with 10 m2 nets)carries 6 nets of 3.0-mm circular mesh. In both systems, 'the underwater unit sends a data frame, comprised of temperature, depth, conductivity, net-frame angle, flow count, time, number of open net, and net opening/closing, to the deck unit in a compressed hexadecimal format every 2 seconds and from the deck unit to a microcomputer every 4 seconds... Temperature (to approximately 0.01 deg C) and conductivity are measured with SEABIRD sensors. Normally, a modified T.S.K.-flowmeter is used... Both the temperature and conductivity sensors and the flow meter are mounted on top of the frame so that they face horizontally when the frame is at a towing angle of 45deg... Calculations of salinity (to approximately 0.01 o/oo S), potential temperature (theta), potential density (sigma), the oblique and vertical velocities of the net, and the approximate volume filtered by each net are made after each string of data has been received by the computer.' (Wiebe et al., 1985) In addition, data were collected from four other sensors attached to the frame: the Transmissometer, the Fluorometer, the Down welling light sensor, and the Oxygen sensor. A SeaBird underwater pump was also included in the sensor suite.

Processing Description
It should be noted that due to Antarctic cold, the first few minutes of data are often of questionable value as they are extremely variable and have a high frequency of '50.000' (indicating 'bad values') in the temp, theta and sal fields. Once the sensors encounter deeper, warmer water, they start recording good values. For additional information, contact the chief scientist for the cruise.

NBP0103

Website
Platform
RVIB Nathaniel B. Palmer
Report
Start Date
2001-04-24
End Date
2001-06-05
Description
Methods & Sampling
The MOCNESS is based on the Tucker Trawl principle (Tucker, 1951). The particular MOCNESS system from which these CTD data came is one of two net systems. The MOCNESS-1 has nine rectangular nets (1m x 1.4 m) which are opened and closed sequentially by commands through conducting cable from the surface (Wiebe et al., 1976). The MOCNESS-10 (with 10 m2 nets)carries 6 nets of 3.0-mm circular mesh. In both systems, 'the underwater unit sends a data frame, comprised of temperature, depth, conductivity, net-frame angle, flow count, time, number of open net, and net opening/closing, to the deck unit in a compressed hexadecimal format every 2 seconds and from the deck unit to a microcomputer every 4 seconds... Temperature (to approximately 0.01 deg C) and conductivity are measured with SEABIRD sensors. Normally, a modified T.S.K.-flowmeter is used... Both the temperature and conductivity sensors and the flow meter are mounted on top of the frame so that they face horizontally when the frame is at a towing angle of 45deg... Calculations of salinity (to approximately 0.01 o/oo S), potential temperature (theta), potential density (sigma), the oblique and vertical velocities of the net, and the approximate volume filtered by each net are made after each string of data has been received by the computer.' (Wiebe et al., 1985) In addition, data were collected from four other sensors attached to the frame: the Transmissometer, the Fluorometer, the Down welling light sensor, and the Oxygen sensor. A SeaBird underwater pump was also included in the sensor suite.

Processing Description
It should be noted that due to Antarctic cold, the first few minutes of data are often of questionable value as they are extremely variable and have a high frequency of '50.000' (indicating 'bad values') in the temp, theta and sal fields. Once the sensors encounter deeper, warmer water, they start recording good values. For additional information, contact the chief scientist for the cruise.

NBP0104

Website
Platform
RVIB Nathaniel B. Palmer
Report
Start Date
2001-07-22
End Date
2001-08-31
Description
Methods & Sampling
The MOCNESS is based on the Tucker Trawl principle (Tucker, 1951). The particular MOCNESS system from which these CTD data came is one of two net systems. The MOCNESS-1 has nine rectangular nets (1m x 1.4 m) which are opened and closed sequentially by commands through conducting cable from the surface (Wiebe et al., 1976). The MOCNESS-10 (with 10 m2 nets)carries 6 nets of 3.0-mm circular mesh. In both systems, 'the underwater unit sends a data frame, comprised of temperature, depth, conductivity, net-frame angle, flow count, time, number of open net, and net opening/closing, to the deck unit in a compressed hexadecimal format every 2 seconds and from the deck unit to a microcomputer every 4 seconds... Temperature (to approximately 0.01 deg C) and conductivity are measured with SEABIRD sensors. Normally, a modified T.S.K.-flowmeter is used... Both the temperature and conductivity sensors and the flow meter are mounted on top of the frame so that they face horizontally when the frame is at a towing angle of 45deg... Calculations of salinity (to approximately 0.01 o/oo S), potential temperature (theta), potential density (sigma), the oblique and vertical velocities of the net, and the approximate volume filtered by each net are made after each string of data has been received by the computer.' (Wiebe et al., 1985) In addition, data were collected from four other sensors attached to the frame: the Transmissometer, the Fluorometer, the Down welling light sensor, and the Oxygen sensor. A SeaBird underwater pump was also included in the sensor suite.

Processing Description
It should be noted that due to Antarctic cold, the first few minutes of data are often of questionable value as they are extremely variable and have a high frequency of '50.000' (indicating 'bad values') in the temp, theta and sal fields. Once the sensors encounter deeper, warmer water, they start recording good values. For additional information, contact the chief scientist for the cruise.

NBP0202

Website
Platform
RVIB Nathaniel B. Palmer
Report
Start Date
2002-04-09
End Date
2002-05-21
Description
Methods & Sampling
The MOCNESS is based on the Tucker Trawl principle (Tucker, 1951). The particular MOCNESS system from which these CTD data came is one of two net systems. The MOCNESS-1 has nine rectangular nets (1m x 1.4 m) which are opened and closed sequentially by commands through conducting cable from the surface (Wiebe et al., 1976). The MOCNESS-10 (with 10 m2 nets)carries 6 nets of 3.0-mm circular mesh. In both systems, 'the underwater unit sends a data frame, comprised of temperature, depth, conductivity, net-frame angle, flow count, time, number of open net, and net opening/closing, to the deck unit in a compressed hexadecimal format every 2 seconds and from the deck unit to a microcomputer every 4 seconds... Temperature (to approximately 0.01 deg C) and conductivity are measured with SEABIRD sensors. Normally, a modified T.S.K.-flowmeter is used... Both the temperature and conductivity sensors and the flow meter are mounted on top of the frame so that they face horizontally when the frame is at a towing angle of 45deg... Calculations of salinity (to approximately 0.01 o/oo S), potential temperature (theta), potential density (sigma), the oblique and vertical velocities of the net, and the approximate volume filtered by each net are made after each string of data has been received by the computer.' (Wiebe et al., 1985) In addition, data were collected from four other sensors attached to the frame: the Transmissometer, the Fluorometer, the Down welling light sensor, and the Oxygen sensor. A SeaBird underwater pump was also included in the sensor suite.

Processing Description
It should be noted that due to Antarctic cold, the first few minutes of data are often of questionable value as they are extremely variable and have a high frequency of '50.000' (indicating 'bad values') in the temp, theta and sal fields. Once the sensors encounter deeper, warmer water, they start recording good values. For additional information, contact the chief scientist for the cruise.

NBP0204

Website
Platform
RVIB Nathaniel B. Palmer
Report
Start Date
2002-07-31
End Date
2002-09-18
Description
Also see NBP0204 Cruise Data Report

Methods & Sampling
The MOCNESS is based on the Tucker Trawl principle (Tucker, 1951). The particular MOCNESS system from which these CTD data came is one of two net systems. The MOCNESS-1 has nine rectangular nets (1m x 1.4 m) which are opened and closed sequentially by commands through conducting cable from the surface (Wiebe et al., 1976). The MOCNESS-10 (with 10 m2 nets)carries 6 nets of 3.0-mm circular mesh. In both systems, 'the underwater unit sends a data frame, comprised of temperature, depth, conductivity, net-frame angle, flow count, time, number of open net, and net opening/closing, to the deck unit in a compressed hexadecimal format every 2 seconds and from the deck unit to a microcomputer every 4 seconds... Temperature (to approximately 0.01 deg C) and conductivity are measured with SEABIRD sensors. Normally, a modified T.S.K.-flowmeter is used... Both the temperature and conductivity sensors and the flow meter are mounted on top of the frame so that they face horizontally when the frame is at a towing angle of 45deg... Calculations of salinity (to approximately 0.01 o/oo S), potential temperature (theta), potential density (sigma), the oblique and vertical velocities of the net, and the approximate volume filtered by each net are made after each string of data has been received by the computer.' (Wiebe et al., 1985) In addition, data were collected from four other sensors attached to the frame: the Transmissometer, the Fluorometer, the Down welling light sensor, and the Oxygen sensor. A SeaBird underwater pump was also included in the sensor suite.

Processing Description
It should be noted that due to Antarctic cold, the first few minutes of data are often of questionable value as they are extremely variable and have a high frequency of '50.000' (indicating 'bad values') in the temp, theta and sal fields. Once the sensors encounter deeper, warmer water, they start recording good values. For additional information, contact the chief scientist for the cruise.


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Project Information

U.S. GLOBEC Southern Ocean (SOGLOBEC)


Coverage: Southern Ocean


The fundamental objectives of United States Global Ocean Ecosystems Dynamics (U.S. GLOBEC) Program are dependent upon the cooperation of scientists from several disciplines. Physicists, biologists, and chemists must make use of data collected during U.S. GLOBEC field programs to further our understanding of the interplay of physics, biology, and chemistry. Our objectives require quantitative analysis of interdisciplinary data sets and, therefore, data must be exchanged between researchers. To extract the full scientific value, data must be made available to the scientific community on a timely basis.



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Program Information

U.S. GLOBal ocean ECosystems dynamics (U.S. GLOBEC)


Coverage: Global


U.S. GLOBEC (GLOBal ocean ECosystems dynamics) is a research program organized by oceanographers and fisheries scientists to address the question of how global climate change may affect the abundance and production of animals in the sea.

The U.S. GLOBEC Program currently had major research efforts underway in the Georges Bank / Northwest Atlantic Region, and the Northeast Pacific (with components in the California Current and in the Coastal Gulf of Alaska). U.S. GLOBEC was a major contributor to International GLOBEC efforts in the Southern Ocean and Western Antarctic Peninsula (WAP).



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Funding

Funding SourceAward
NSF Antarctic Sciences (NSF ANT)

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