CTD fluorometric chlorophyll a and total phaeopigment 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/2653
Version: June 24, 2002
Version Date: 2002-06-24

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

Program
» U.S. Joint Global Ocean Flux Study (U.S. JGOFS)
ContributorsAffiliationRole
Murray, James W.University of Washington (UW)Principal Investigator
Newton, JanUniversity of Washington (UW)Principal Investigator
Chandler, Cynthia L.Woods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager


Dataset Description

CTD Fluorometric chlorophyll a and total phaeopigment

Acquisition Description

See Platform deployments for cruise specific documentation


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Parameters

ParameterDescriptionUnits
eventevent/operation number from event log
stastation number from event log
castCTD cast number from event log
commentfree text data quality notes
botCTD rosette bottle number
depth_nnominal sample depth meters
fluor_vol_filtvolume of sample filtered liters
scalesensitivity scale on the fluorometer
dfdoor factor; true value of sensitivity scale
Bcalibration factor
Fooriginal fluorometer reading
Fafluorometer reading after 2 drops 1N HCL
chl_a_fluorchlorophyll a; fluorometric method micrograms/liter
phaeototal phaeopigment micrograms/liter
Fo_to_FaFo to Fa ratio. ranges between max. 2.10, all chlorophyll-a no Phaeopigment min. 1.00, no chlorophyll-a all Phaeopigment


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Instruments

Dataset-specific Instrument Name
Niskin Bottle
Generic Instrument Name
Niskin bottle
Dataset-specific Description
CTD clean rosette (Niskin) bottles were used to collect water samples.
Generic Instrument Description
A Niskin bottle (a next generation water sampler based on the Nansen bottle) is a cylindrical, non-metallic water collection device with stoppers at both ends. The bottles can be attached individually on a hydrowire or deployed in 12, 24, or 36 bottle Rosette systems mounted on a frame and combined with a CTD. Niskin bottles are used to collect discrete water samples for a range of measurements including pigments, nutrients, plankton, etc.


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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: Jan Newton/James Murray of: University of Washington dataset: CTD Fluorometric chlorophyll a and total phaeopigment dates: February 05, 1992 to March 08, 1992 location: N: 12.0284 S: -12.2083 W: -140.7452 E: -134.7269 project/cruise: EQPAC/TT007 - Spring Survey ship: Thomas Thompson PI note: Due to chlorophyll degradation by the acetone (reagent grade, in cans) the data for the following CTD casts have been deleted from the file: 1, 3, 5, 6, 7, 8, 20, 23, 25, 30, 33, 35, 37 and 38.

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: Jan Newton and James Murray of: University of Washington dataset: CTD Fluorometric chlorophyll a and total phaeopigment dates: August 10, 1992 to September 15, 1992 location: N: 12.0183 S: -11.9667 W: -141.4433 E: -134.9267 project/cruise: EQPAC/TT011 - Fall Survey ship: Thomas Thompson EqPac bottle quality review summary from DMO


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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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