Fatty acid fluxes from sediment trap samples from R/V Thomas G. Thompson cruises TT007, TT011 in the Equatorial Pacific in 1992 during the U.S. JGOFS Equatorial Pacific (EqPac) project

Website: https://www.bco-dmo.org/dataset/2670
Version: December 1, 1995
Version Date: 1995-12-01

Project
» U.S. JGOFS Equatorial Pacific (EqPac)

Program
» U.S. Joint Global Ocean Flux Study (U.S. JGOFS)
ContributorsAffiliationRole
Wakeham, StuartSkidaway Institute of Oceanography (SkIO)Principal Investigator
Chandler, Cynthia L.Woods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager


Dataset Description

Fatty acid fluxes, Indented Rotary Sphere (IRS) Floating sediment trap samples

Acquisition Description

See Platform deployments for cruise specific documentation


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Parameters

ParameterDescriptionUnits
n12 thru s12nominal latitudes for trap deployments along 140W degrees
Fatty_acidfluxes of fatty acids names have been prefixed with (fa_). This prefix must be ignored when deciphering the fatty acid name. Names are defined as number carbon atoms:number of double bonds. Prefixes i=iso, a=anteiso. ug/m^2/d


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Instruments

Dataset-specific Instrument Name
IRS Sediment Trap
Generic Instrument Name
Sediment Trap - IRS
Generic Instrument Description
Sediment traps are specially designed containers deployed in the water column for periods of time to collect particles from the water column falling toward the sea floor. In general a sediment trap has a jar at the bottom to collect the sample and a broad funnel-shaped opening at the top with baffles to keep out very large objects and help prevent the funnel from clogging. The Indented Rotating Sphere (IRS) Sediment Trap is described in Peterson et al. (Field evaluation of a valved sediment trap. 1993. Limnology and Oceanography, 38, pp. 1741-1761 and Novel techniques for collection of sinking particles in the ocean and determining their settling rates. 2005. Limnology and Oceanography Methods 3, pp. 520-532). The IRS trap consists of four cylindrical modules; a particle interceptor, an IRS valve; a skewed funnel, and an eleven sample carousel (designated IRSC trap). The key to the trap design is the patented IRS valve located between the particle interceptor and particle accumulator portions of the trap. The valve and carousel are regulated by a TattleTale IVA (manufactured by Onset Computer Corp.) microprocessor and custom software. The IRS sediment trap was specifically designed to exclude zooplankton (Trull et al. 2008. Deep-Sea Research II v.55 pp. 1684-1695).


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Deployments

TT007

Website
Platform
R/V Thomas G. Thompson
Start Date
1992-01-30
End Date
1992-03-13
Description
Purpose: Spring Survey Cruise; 12°N-12°S at 140°W TT007 was one of five cruises conducted in 1992 in support of the U.S. Equatorial Pacific (EqPac) Process Study. The five EqPac cruises aboard R/V Thomas G. Thompson included two repeat meridional sections (12°N - 12°S), 2 equatorial surveys, and a benthic survey (all at 140° W). The scientific objectives of this study were to observe the processes in the Equatorial Pacific controlling the fluxes of carbon and related elements between the atmosphere, euphotic zone, and deep ocean. As luck would have it, the survey window coincided with an El Nino event. A bonus for the research team.

Acquisition Description
PI: Stuart Wakeham dataset: Fatty acid fluxes, Indented Rotary Sphere sediment trap samples dates: February 3, 1992 to March 9, 1992 location: N: 12 S: -12 W: -140 E: -140 project/cruise: EqPac/TT007 - Spring Survey ship: Thomas Thompson Sampling Methodology: Traps deployed at 100 meters for durations of 1.5 to 2.5 days. For specifics on trap deployment/recovery positions and times see event log, PI Hedges. Methodology: Sediment trap material was filtered onto 90 mm glass fiber filters (A/E) and frozen. Filters with trap material and sediments were Soxhlet extracted with methylene chloride-methanol (2:1) and the extracts partitioned into the organic phase with 5% NaCl. The "lipid extracts" were saponified with 0.5N KOH/methanol, with "neutral lipids" extracted out of basic solution and "acids" extracted out of acidic solution. Neutral lipids were silylated with BSTFA and fatty acids were methylated with diazomethane. Anaylsis was by gas chromatography and gas chromatography-mass spectrometry. Notes: Note due to the nature of this data set the standard suite of data manipulative tools (plot/other options) on the JGOFS Data System do not apply. Fatty_acid names have been prefixed with (fa_). This prefix must be ignored when deciphering the true fatty acid name. Names are defined as number carbon atoms:number of double bonds. Prefixes i=iso, a=anteiso. The field labels n12 thru s12 are nominal latitudes for trap deployments along 140 west.

TT011

Website
Platform
R/V Thomas G. Thompson
Start Date
1992-08-05
End Date
1992-09-18
Description
Purpose: Fall Survey; 12°N-12°S at 140°W TT011 was one of five cruises conducted in 1992 in support of the U.S. Equatorial Pacific (EqPac) Process Study. The five EqPac cruises aboard R/V Thomas G. Thompson included two repeat meridional sections (12°N - 12°S), 2 equatorial surveys, and a benthic survey (all at 140° W). The scientific objectives of this study were to observe the processes in the Equatorial Pacific controlling the fluxes of carbon and related elements between the atmosphere, euphotic zone, and deep ocean. As luck would have it, the survey window coincided with an El Nino event. A bonus for the research team.

Acquisition Description
PI: Stuart Wakeham dataset: Fatty acid fluxes, Indented Rotary Sphere sediment trap samples dates: August 5, 1992 to September 18, 1992 location: N: 12 S: -12 W: -140 E: -140 project/cruise: EqPac/TT011 - Fall Survey ship: Thomas Thompson Sampling Methodology: Traps deployed at 100 meters for durations of 1.5 to 2.5 days. For specifics on trap deployment/recovery positions and times see event log, PI Hedges. Methodology: Sediment trap material was filtered onto 90 mm glass fiber filters (A/E) and frozen. Filters with trap material and sediments were Soxhlet extracted with methylene chloride-methanol (2:1) and the extracts partitioned into the organic phase with 5% NaCl. The "lipid extracts" were saponified with 0.5N KOH/methanol, with "neutral lipids" extracted out of basic solution and "acids" extracted out of acidic solution. Neutral lipids were silylated with BSTFA and fatty acids were methylated with diazomethane. Anaylsis was by gas chromatography and gas chromatography-mass spectrometry. Notes: Note due to the nature of this data set the standard suite of data manipulative tools (plot/other options) on the JGOFS Data System do not apply. fatty_acid names have been prefixed with (fa_) and this prefix must be ignored when deciphering the true fatty acid name. Names are defined as number carbon atoms:number of double bonds. Prefixes i=iso, a=anteiso. The field labels n12 thru s12 are nominal latitudes for trap deployments along 140 west. Traps deployed at 100 meters for durations of 1.5 to 2.5 days. For specifics on trap deployment/recovery positions and times see event log, PI Hedges. fatty acid fluxes = reported as ug/m^2/day nd = no/bad data


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Project Information

U.S. JGOFS Equatorial Pacific (EqPac)


Coverage: Equatorial Pacific


The U.S. EqPac process study consisted of repeat meridional sections (12°N -12°S) across the equator in the central and eastern equatorial Pacific from 95°W to 170°W during 1992. The major scientific program was focused at 140° W consisting of two meridional surveys, two equatorial surveys, and a benthic survey aboard the R/V Thomas Thompson. Long-term deployments of current meter and sediment trap arrays augmented the survey cruises. NOAA conducted boreal spring and fall sections east and west of 140°W from the R/V Baldridge and R/V Discoverer. Meteorological and sea surface observations were obtained from NOAA's in place TOGA-TAO buoy network.

The scientific objectives of this study were to determine the fluxes of carbon and related elements, and the processes controlling these fluxes between the Equatorial Pacific euphotic zone and the atmosphere and deep ocean. A broad overview of the program at the 140°W site is given by Murray et al. (Oceanography, 5: 134-142, 1992). A full description of the Equatorial Pacific Process Study, including the international context and the scientific results, appears in a series of Deep-Sea Research Part II special volumes:

Topical Studies in Oceanography, A U.S. JGOFS Process Study in the Equatorial Pacific (1995), Deep-Sea Research Part II, Volume 42, No. 2/3.

Topical Studies in Oceanography, A U.S. JGOFS Process Study in the Equatorial Pacific. Part 2 (1996), Deep-Sea Research Part II, Volume 43, No. 4/6.

Topical Studies in Oceanography, A U.S. JGOFS Process Study in the Equatorial Pacific (1997), Deep-Sea Research Part II, Volume 44, No. 9/10.

Topical Studies in Oceanography, The Equatorial Pacific JGOFS Synthesis (2002), Deep-Sea Research Part II, Volume 49, Nos. 13/14.



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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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