Zooplankton carbon by size fractions from MOCNESS tows from R/V Thomas G. Thompson TT043, TT045, TT050, TT054 cruises in the Arabian Sea in 1995 (U.S. JGOFS Arabian Sea project)

Website: https://www.bco-dmo.org/dataset/2974
Version: July 2, 1997
Version Date: 1997-07-02

Project
» U.S. JGOFS Arabian Sea (Arabian Sea)

Program
» U.S. Joint Global Ocean Flux Study (U.S. JGOFS)
ContributorsAffiliationRole
Wishner, KarenUniversity of Rhode Island (URI-GSO)Principal Investigator
Gowing, MarciaUniversity of California-Santa Cruz (UCSC)Co-Principal Investigator
Chandler, Cynthia L.Woods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager


Dataset Description

Zooplankton carbon by size fractions for each net, double 1 m2 MOCNESS net tows


Methods & Sampling

See Platform deployments for cruise specific documentation


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Parameters

ParameterDescriptionUnits
eventunique event number MMDDHHmm
sta_stdstandard station number
stastation number from event log
towMOCNESS tow number
netnet number
depth_begindepth at which net opened meters
depth_enddepth at which net closed meters
vol_filtvolume of water filtered by the net cubic meters
zp_C_1zooplankton carbon, 200-500 micron mmol C/m3
zp_C_2zooplankton carbon, 500-1000 micron mmol C/m3
zp_C_3zooplankton carbon, 1000-2000 micron mmol C/m3
zp_C_4zooplankton carbon, gt 2000 micron mmol C/m3
zp_C_Tzooplankton carbon, total size fractions mmol C/m3


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Instruments

Dataset-specific Instrument Name
MOCNESS1
Generic Instrument Name
MOCNESS1
Generic Instrument Description
The Multiple Opening/Closing Net and Environmental Sensing System or MOCNESS is a family of net systems based on the Tucker Trawl principle. The MOCNESS-1 carries nine 1-m2 nets usually of 335 micrometer mesh and is intended for use with the macrozooplankton. All nets are black to reduce contrast with the background. A motor/toggle release assembly is mounted on the top portion of the frame and stainless steel cables with swaged fittings are used to attach the net bar to the toggle release. A stepping motor in a pressure compensated case filled with oil turns the escapement crankshaft of the toggle release which sequentially releases the nets to an open then closed position on command from the surface. -- from the MOCNESS Operations Manual (1999 + 2003).

Dataset-specific Instrument Name
MOCNESS
Generic Instrument Name
MOCNESS
Generic Instrument Description
The Multiple Opening/Closing Net and Environmental Sensing System or MOCNESS is a family of net systems based on the Tucker Trawl principle. There are currently 8 different sizes of MOCNESS in existence which are designed for capture of different size ranges of zooplankton and micro-nekton Each system is designated according to the size of the net mouth opening and in two cases, the number of nets it carries. The original MOCNESS (Wiebe et al, 1976) was a redesigned and improved version of a system described by Frost and McCrone (1974).(from MOCNESS manual) This designation is used when the specific type of MOCNESS (number and size of nets) was not specified by the contributing investigator.


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Deployments

TT043

Website
Platform
R/V Thomas G. Thompson
Report
Start Date
1995-01-08
End Date
1995-02-05
Description
Purpose: Process Cruise #1 (Late NE Monsoon)

Methods & Sampling
PI: Karen Wishner (University of Rhode Island), Marcia Gowing (University of California- Santa Cruz) dataset: Zooplankton carbon by size fractions for each net, double 1 m2 MOCNESS net tows dates: January 12, 1995 to January 29, 1995 location: N: 19.1021 S: 10.0025 W: 58.0247 E: 68.7495 project: Arabian Sea cruise: TTN-043, Process 1, Winter monsoon ship: R/V Thomas Thompson Mesozooplankton Biomass Documentation: JGOFS Arabian Sea PIs: Karen Wishner (URI), Marcia Gowing (UCSC) Data Base Organizer and Chief Technician: Celia Gelfman Assistants: Chelsea Donovan, Heidi Franklin, Maureen Koneval, Lauren Lankau, John Maccario, Jennifer Saltzman, Dorothee Schreiber, Cynthia Venn, Kathleen Vignes. Samples were collected with a double 1 m2 MOCNESS (two 1 m2 MOCNESS systems side-by-side), a multiple opening-closing net system with environmental sensors and control of the nets from shipboard (Wiebe et al. 1976, 1985). The nets were 153 micron mesh with a 1 m2 mouth opening (when towed at a 45 degree angle). The net was towed usually at 1.5 - 2.5 kts behind the ship. Wire was payed out at 10 - 25 m/min and hauled in at 5 - 20 m/min. Environmental data from the MOCNESS included time, depth, temperature (Sea-Bird SBE 3), salinity (Sea-Bird SBE 4), light transmission (SeaTech 25 cm beam transmissometer), and oxygen (Sea-Bird SBE 13). The volume filtered through each net was determined by the MOCNESS program, taking into account flow past the system (measured with a modified TSK flowmeter mounted on the net frame) and the towing angle. In some cases, the volume filtered per time from trouble-free portions of a tow was extrapolated to time intervals with electronic problems. Usually 16 discrete samples were collected in an oblique haul from about 1000 m to the surface. Typically a day and a night tow were taken at each of the six long stations during four seasonally-spaced process cruises (TN043, TN045, TN050, TN054). Occasional additional tows and samples to deeper depths were also done. During the monsoon cruise (TN050), there were often problems with knotted or ripped nets because of the rough seas; data from this cruise should be treated with caution. Tow times and geographic locations can be found in the cruise event log. Cod ends were placed on ice immediately after retrieval. Nets were hosed down with filtered (nominally 2 micron) seawater. For most day tows, the entire sample was preserved in 4% borate-buffered formaldehyde. For most night tows, the samples were split in a NMFS-style (flat-bottomed) plankton splitter. Half the sample was preserved as above for displacement volumes, wet weights, and distributions; one quarter (or the entire remaining half for very small samples and for surface samples) was set aside in a refrigerator for dry weight and CHN subsampling several hours later; and one quarter (when available) was preserved in paraformaldehyde for electron microscopy of zooplankton gut contents. For dry weights, the sample was size-fractionated through a sieve series (2000, 1000, 505, 202 micron) and each size fraction was resuspended in a known volume of filtered seawater. Aliquots were taken with a Stempel piston pipette, filtered onto combusted pre-weighed GF/D 25 mm glass fiber filters, rinsed with distilled water, loosely wrapped in aluminum foil, placed in an oven (60 degrees C) for several days, and stored in a desiccator for shipment home. Two replicates were done for each size fraction. Four blanks (aliquots of filtered seawater treated as above) were done for each tow. In the lab, filters were dried in an oven (60 degrees C) for 8 - 10 hr, weighed for dry weight on a Cahn microbalance, ashed in a muffle furnace (500 degrees C) for 4 hr, and weighed for ash. For dry weights, the pre-cruise filter weight and the mean dry weight blank for the cruise (a single value for each cruise) were subtracted from the measured post-cruise dry weights. The ash-free dry weight was calculated as the post-cruise dry weight minus the post-cruise ash weight and the cruise mean ash weight blank. For carbon values, a conversion factor from the literature was used [log (dry weight) = 0.499 + 0.991 (log carbon)] (Wiebe et al. 1975, Wiebe 1988). The mean of the 2 replicate filters from each sample was used. In cases where no measurements were made and in cases where the weight of a filter with sample was less than the blank and pre-cruise filter weight, the data were recorded as ND (no data). Carbon values from CHN measurements were also obtained by Roman from some of these same samples in the upper 200 m on cruises TN043, TN045, and TN050. Displacement volumes and wet weights were measured several months after the cruise on preserved samples. Either the entire sample or a half split was used. Large singular organisms (large fish or jellyfish) were removed beforehand. Displacement volumes were done with no size fractionation. Wet weights were done on the large (> 2 mm) and small (

TT045

Website
Platform
R/V Thomas G. Thompson
Start Date
1995-03-14
End Date
1995-04-10
Description
Methods & Sampling
PI: Karen Wishner (University of Rhode Island), Marcia Gowing (University of California-Santa Cruz) dataset: Zooplankton carbon by size fractions for each net, double 1 m2 MOCNESS net tows dates: March 18, 1995 to April 06, 1995 location: N: 19.1664 S: 14.4955 W: 57.9971 E: 67.1663 project: Arabian Sea cruise: TTN-045, Process 2 (Spring Intermonsoon) ship: R/V Thomas Thompson Mesozooplankton Biomass Documentation: JGOFS Arabian Sea PIs: Karen Wishner (URI), Marcia Gowing (UCSC) Data Base Organizer and Chief Technician: Celia Gelfman Assistants: Chelsea Donovan, Heidi Franklin, Maureen Koneval, Lauren Lankau, John Maccario, Jennifer Saltzman, Dorothee Schreiber, Cynthia Venn, Kathleen Vignes. Samples were collected with a double 1 m2 MOCNESS (two 1 m2 MOCNESS systems side-by-side), a multiple opening-closing net system with environmental sensors and control of the nets from shipboard (Wiebe et al. 1976, 1985). The nets were 153 micron mesh with a 1 m2 mouth opening (when towed at a 45 degree angle). The net was towed usually at 1.5 - 2.5 kts behind the ship. Wire was payed out at 10 - 25 m/min and hauled in at 5 - 20 m/min. Environmental data from the MOCNESS included time, depth, temperature (Sea-Bird SBE 3), salinity (Sea-Bird SBE 4), light transmission (SeaTech 25 cm beam transmissometer), and oxygen (Sea-Bird SBE 13). The volume filtered through each net was determined by the MOCNESS program, taking into account flow past the system (measured with a modified TSK flowmeter mounted on the net frame) and the towing angle. In some cases, the volume filtered per time from trouble-free portions of a tow was extrapolated to time intervals with electronic problems. Usually 16 discrete samples were collected in an oblique haul from about 1000 m to the surface. Typically a day and a night tow were taken at each of the six long stations during four seasonally-spaced process cruises (TN043, TN045, TN050, TN054). Occasional additional tows and samples to deeper depths were also done. During the monsoon cruise (TN050), there were often problems with knotted or ripped nets because of the rough seas; data from this cruise should be treated with caution. Tow times and geographic locations can be found in the cruise event log. Cod ends were placed on ice immediately after retrieval. Nets were hosed down with filtered (nominally 2 micron) seawater. For most day tows, the entire sample was preserved in 4% borate-buffered formaldehyde. For most night tows, the samples were split in a NMFS-style (flat-bottomed) plankton splitter. Half the sample was preserved as above for displacement volumes, wet weights, and distributions; one quarter (or the entire remaining half for very small samples and for surface samples) was set aside in a refrigerator for dry weight and CHN subsampling several hours later; and one quarter (when available) was preserved in paraformaldehyde for electron microscopy of zooplankton gut contents. For dry weights, the sample was size-fractionated through a sieve series (2000, 1000, 505, 202 micron) and each size fraction was resuspended in a known volume of filtered seawater. Aliquots were taken with a Stempel piston pipette, filtered onto combusted pre-weighed GF/D 25 mm glass fiber filters, rinsed with distilled water, loosely wrapped in aluminum foil, placed in an oven (60 degrees C) for several days, and stored in a desiccator for shipment home. Two replicates were done for each size fraction. Four blanks (aliquots of filtered seawater treated as above) were done for each tow. In the lab, filters were dried in an oven (60 degrees C) for 8 - 10 hr, weighed for dry weight on a Cahn microbalance, ashed in a muffle furnace (500 degrees C) for 4 hr, and weighed for ash. For dry weights, the pre-cruise filter weight and the mean dry weight blank for the cruise (a single value for each cruise) were subtracted from the measured post-cruise dry weights. The ash-free dry weight was calculated as the post-cruise dry weight minus the post-cruise ash weight and the cruise mean ash weight blank. For carbon values, a conversion factor from the literature was used [log (dry weight) = 0.499 + 0.991 (log carbon)] (Wiebe et al. 1975, Wiebe 1988). The mean of the 2 replicate filters from each sample was used. In cases where no measurements were made and in cases where the weight of a filter with sample was less than the blank and pre-cruise filter weight, the data were recorded as ND (no data). Carbon values from CHN measurements were also obtained by Roman from some of these same samples in the upper 200 m on cruises TN043, TN045, and TN050. Displacement volumes and wet weights were measured several months after the cruise on preserved samples. Either the entire sample or a half split was used. Large singular organisms (large fish or jellyfish) were removed beforehand. Displacement volumes were done with no size fractionation. Wet weights were done on the large (> 2 mm) and small (

TT050

Website
Platform
R/V Thomas G. Thompson
Start Date
1995-08-18
End Date
1995-09-15
Description
Methods & Sampling
PI: Karen Wishner (University of Rhode Island), Marcia Gowing (University of California-Santa Cruz) dataset: Zooplankton carbon by size fractions for each net, double 1 m2 MOCNESS net tows project: Arabian Sea cruise: TTN-050, Process 5 ship: R/V Thomas Thompson Mesozooplankton Biomass Documentation: JGOFS Arabian Sea PIs: Karen Wishner (URI), Marcia Gowing (UCSC) Data Base Organizer and Chief Technician: Celia Gelfman Assistants: Chelsea Donovan, Heidi Franklin, Maureen Koneval, Lauren Lankau, John Maccario, Jennifer Saltzman, Dorothee Schreiber, Cynthia Venn, Kathleen Vignes. Samples were collected with a double 1 m2 MOCNESS (two 1 m2 MOCNESS systems side-by-side), a multiple opening-closing net system with environmental sensors and control of the nets from shipboard (Wiebe et al. 1976, 1985). The nets were 153 micron mesh with a 1 m2 mouth opening (when towed at a 45 degree angle). The net was towed usually at 1.5 - 2.5 kts behind the ship. Wire was payed out at 10 - 25 m/min and hauled in at 5 - 20 m/min. Environmental data from the MOCNESS included time, depth, temperature (Sea-Bird SBE 3), salinity (Sea-Bird SBE 4), light transmission (SeaTech 25 cm beam transmissometer), and oxygen (Sea-Bird SBE 13). The volume filtered through each net was determined by the MOCNESS program, taking into account flow past the system (measured with a modified TSK flowmeter mounted on the net frame) and the towing angle. In some cases, the volume filtered per time from trouble-free portions of a tow was extrapolated to time intervals with electronic problems. Usually 16 discrete samples were collected in an oblique haul from about 1000 m to the surface. Typically a day and a night tow were taken at each of the six long stations during four seasonally-spaced process cruises (TN043, TN045, TN050, TN054). Occasional additional tows and samples to deeper depths were also done. During the monsoon cruise (TN050), there were often problems with knotted or ripped nets because of the rough seas; data from this cruise should be treated with caution. Tow times and geographic locations can be found in the cruise event log. Cod ends were placed on ice immediately after retrieval. Nets were hosed down with filtered (nominally 2 micron) seawater. For most day tows, the entire sample was preserved in 4% borate-buffered formaldehyde. For most night tows, the samples were split in a NMFS-style (flat-bottomed) plankton splitter. Half the sample was preserved as above for displacement volumes, wet weights, and distributions; one quarter (or the entire remaining half for very small samples and for surface samples) was set aside in a refrigerator for dry weight and CHN subsampling several hours later; and one quarter (when available) was preserved in paraformaldehyde for electron microscopy of zooplankton gut contents. For dry weights, the sample was size-fractionated through a sieve series (2000, 1000, 505, 202 micron) and each size fraction was resuspended in a known volume of filtered seawater. Aliquots were taken with a Stempel piston pipette, filtered onto combusted pre-weighed GF/D 25 mm glass fiber filters, rinsed with distilled water, loosely wrapped in aluminum foil, placed in an oven (60 degrees C) for several days, and stored in a desiccator for shipment home. Two replicates were done for each size fraction. Four blanks (aliquots of filtered seawater treated as above) were done for each tow. In the lab, filters were dried in an oven (60 degrees C) for 8 - 10 hr, weighed for dry weight on a Cahn microbalance, ashed in a muffle furnace (500 degrees C) for 4 hr, and weighed for ash. For dry weights, the pre-cruise filter weight and the mean dry weight blank for the cruise (a single value for each cruise) were subtracted from the measured post-cruise dry weights. The ash-free dry weight was calculated as the post-cruise dry weight minus the post-cruise ash weight and the cruise mean ash weight blank. For carbon values, a conversion factor from the literature was used [log (dry weight) = 0.499 + 0.991 (log carbon)] (Wiebe et al. 1975, Wiebe 1988). The mean of the 2 replicate filters from each sample was used. In cases where no measurements were made and in cases where the weight of a filter with sample was less than the blank and pre-cruise filter weight, the data were recorded as ND (no data). Carbon values from CHN measurements were also obtained by Roman from some of these same samples in the upper 200 m on cruises TN043, TN045, and TN050. Displacement volumes and wet weights were measured several months after the cruise on preserved samples. Either the entire sample or a half split was used. Large singular organisms (large fish or jellyfish) were removed beforehand. Displacement volumes were done with no size fractionation. Wet weights were done on the large (> 2 mm) and small (

TT054

Website
Platform
R/V Thomas G. Thompson
Start Date
1995-11-30
End Date
1995-12-28
Description
Methods & Sampling
PI: Karen Wishner (University of Rhode Island) and Marcia Gowing (University of California - Santa Cruz) dataset: Zooplankton carbon by size fractions for each net, double 1 m2 MOCNESS net tows dates: December 04, 1995 to December 23, 1995 location: N: 19.2139 S: 10.0421 W: 58.0225 E: 67.1631 project: Arabian Sea cruise: TTN-054, Process 7 (Early NE Monsoon) ship: R/V Thomas Thompson Mesozooplankton Biomass Documentation: JGOFS Arabian Sea PIs: Karen Wishner (URI), Marcia Gowing (UCSC) Data Base Organizer and Chief Technician: Celia Gelfman Assistants: Chelsea Donovan, Heidi Franklin, Maureen Koneval, Lauren Lankau, John Maccario, Jennifer Saltzman, Dorothee Schreiber, Cynthia Venn, Kathleen Vignes. Samples were collected with a double 1 m2 MOCNESS (two 1 m2 MOCNESS systems side-by-side), a multiple opening-closing net system with environmental sensors and control of the nets from shipboard (Wiebe et al. 1976, 1985). The nets were 153 micron mesh with a 1 m2 mouth opening (when towed at a 45 degree angle). The net was towed usually at 1.5 - 2.5 kts behind the ship. Wire was payed out at 10 - 25 m/min and hauled in at 5 - 20 m/min. Environmental data from the MOCNESS included time, depth, temperature (Sea-Bird SBE 3), salinity (Sea-Bird SBE 4), light transmission (SeaTech 25 cm beam transmissometer), and oxygen (Sea-Bird SBE 13). The volume filtered through each net was determined by the MOCNESS program, taking into account flow past the system (measured with a modified TSK flowmeter mounted on the net frame) and the towing angle. In some cases, the volume filtered per time from trouble-free portions of a tow was extrapolated to time intervals with electronic problems. Usually 16 discrete samples were collected in an oblique haul from about 1000 m to the surface. Typically a day and a night tow were taken at each of the six long stations during four seasonally-spaced process cruises (TN043, TN045, TN050, TN054). Occasional additional tows and samples to deeper depths were also done. During the monsoon cruise (TN050), there were often problems with knotted or ripped nets because of the rough seas; data from this cruise should be treated with caution. Tow times and geographic locations can be found in the cruise event log. Cod ends were placed on ice immediately after retrieval. Nets were hosed down with filtered (nominally 2 micron) seawater. For most day tows, the entire sample was preserved in 4% borate-buffered formaldehyde. For most night tows, the samples were split in a NMFS-style (flat-bottomed) plankton splitter. Half the sample was preserved as above for displacement volumes, wet weights, and distributions; one quarter (or the entire remaining half for very small samples and for surface samples) was set aside in a refrigerator for dry weight and CHN subsampling several hours later; and one quarter (when available) was preserved in paraformaldehyde for electron microscopy of zooplankton gut contents. For dry weights, the sample was size-fractionated through a sieve series (2000, 1000, 505, 202 micron) and each size fraction was resuspended in a known volume of filtered seawater. Aliquots were taken with a Stempel piston pipette, filtered onto combusted pre-weighed GF/D 25 mm glass fiber filters, rinsed with distilled water, loosely wrapped in aluminum foil, placed in an oven (60 degrees C) for several days, and stored in a desiccator for shipment home. Two replicates were done for each size fraction. Four blanks (aliquots of filtered seawater treated as above) were done for each tow. In the lab, filters were dried in an oven (60 degrees C) for 8 - 10 hr, weighed for dry weight on a Cahn microbalance, ashed in a muffle furnace (500 degrees C) for 4 hr, and weighed for ash. For dry weights, the pre-cruise filter weight and the mean dry weight blank for the cruise (a single value for each cruise) were subtracted from the measured post-cruise dry weights. The ash-free dry weight was calculated as the post-cruise dry weight minus the post-cruise ash weight and the cruise mean ash weight blank. For carbon values, a conversion factor from the literature was used [log (dry weight) = 0.499 + 0.991 (log carbon)] (Wiebe et al. 1975, Wiebe 1988). The mean of the 2 replicate filters from each sample was used. In cases where no measurements were made and in cases where the weight of a filter with sample was less than the blank and pre-cruise filter weight, the data were recorded as ND (no data). Carbon values from CHN measurements were also obtained by Roman from some of these same samples in the upper 200 m on cruises TN043, TN045, and TN050. Displacement volumes and wet weights were measured several months after the cruise on preserved samples. Either the entire sample or a half split was used. Large singular organisms (large fish or jellyfish) were removed beforehand. Displacement volumes were done with no size fractionation. Wet weights were done on the large (> 2 mm) and small (


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Project Information

U.S. JGOFS Arabian Sea (Arabian Sea)


Coverage: Arabian Sea


The U.S. Arabian Sea Expedition which began in September 1994 and ended in January 1996, had three major components: a U.S. JGOFS Process Study, supported by the National Science Foundation (NSF); Forced Upper Ocean Dynamics, an Office of Naval Research (ONR) initiative; and shipboard and aircraft measurements supported by the National Aeronautics and Space Administration (NASA). The Expedition consisted of 17 cruises aboard the R/V Thomas Thompson, year-long moored deployments of five instrumented surface buoys and five sediment-trap arrays, aircraft overflights and satellite observations. Of the seventeen ship cruises, six were allocated to repeat process survey cruises, four to SeaSoar mapping cruises, six to mooring and benthic work, and a single calibration cruise which was essentially conducted in transit to the Arabian Sea.



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Program Information

U.S. Joint Global Ocean Flux Study (U.S. JGOFS)


Coverage: Global


The United States Joint Global Ocean Flux Study was a national component of international JGOFS and an integral part of global climate change research.

The U.S. launched the Joint Global Ocean Flux Study (JGOFS) in the late 1980s to study the ocean carbon cycle. An ambitious goal was set to understand the controls on the concentrations and fluxes of carbon and associated nutrients in the ocean. A new field of ocean biogeochemistry emerged with an emphasis on quality measurements of carbon system parameters and interdisciplinary field studies of the biological, chemical and physical process which control the ocean carbon cycle. As we studied ocean biogeochemistry, we learned that our simple views of carbon uptake and transport were severely limited, and a new "wave" of ocean science was born. U.S. JGOFS has been supported primarily by the U.S. National Science Foundation in collaboration with the National Oceanic and Atmospheric Administration, the National Aeronautics and Space Administration, the Department of Energy and the Office of Naval Research. U.S. JGOFS, ended in 2005 with the conclusion of the Synthesis and Modeling Project (SMP).



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Funding

Funding SourceAward
NSF Division of Ocean Sciences (NSF OCE)

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