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Dataset Overview | National Centers for Environmental Information (NCEI)

CTD cast data from 45 R/V Alpha Helix and R/V Wecoma Long-Term Observation Program (LTOP) cruises to the Coastal Gulf of Alaska from 1997-2004 as part of the U.S. GLOBEC program (NEP project) (NCEI Accession 0113922)

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This dataset contains biological, meteorological, optical, and physical data collected on R/V Alpha Helix and R/V Wecoma during cruises HX201, HX203, HX205, HX208, HX211, HX215, HX216, HX217, HX218, HX219, HX223, HX225, HX226, HX228, HX230, HX231, HX234, HX237, HX238, HX239, HX241, HX243, HX246, HX248, HX252, HX253, HX254, HX257, HX258, HX262, HX263, HX267, HX268, HX269, HX270, HX272, HX276, HX279, HX280, HX281, HX283, HX286, HX292, HX293, and W0307A in the Gulf of Alaska from 1997-10-10 to 2004-12-09. These data include PAR, barometric pressure, fluorescence, light transmission (volts), salinity calculated from CTD primary sensors, sigma-t, and temp2. The instruments used to collect these data include CTD profiler. These data were collected by Dr Thomas J. Weingartner of University of Alaska Fairbanks as part of the "U.S. GLOBEC Northeast Pacific (NEP)" project and "U.S. GLOBal ocean ECosystems dynamics (U.S. GLOBEC)" program. The Biological and Chemical Oceanography Data Management Office (BCO-DMO) submitted these data to NCEI on 2019-11-28.

The following is the text of the dataset description provided by BCO-DMO:

AK-LTOP CTD cast data

Dataset Description:
CTD datasets from the CGOA LTOP project

Contributor: Tom Weingartner
  • Cite as: Weingartner, Thomas J. (2013). CTD cast data from 45 R/V Alpha Helix and R/V Wecoma Long-Term Observation Program (LTOP) cruises to the Coastal Gulf of Alaska from 1997-2004 as part of the U.S. GLOBEC program (NEP project) (NCEI Accession 0113922). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://www.ncei.noaa.gov/archive/accession/0113922. Accessed [date].
gov.noaa.nodc:0113922
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Distribution Formats
  • TSV
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Distributor NOAA National Centers for Environmental Information
+1-301-713-3277
NCEI.Info@noaa.gov
Dataset Point of Contact NOAA National Centers for Environmental Information
ncei.info@noaa.gov
Time Period 1997-10-10 to 2004-12-09
Spatial Bounding Box Coordinates
West: -150.936
East: -143.669
South: 57.8
North: 61.26
Spatial Coverage Map
General Documentation
Associated Resources
  • Biological, chemical, physical, biogeochemical, ecological, environmental and other data collected from around the world during historical and contemporary periods of biological and chemical oceanographic exploration and research managed and submitted by the Biological and Chemical Oceanography Data Management Office (BCO-DMO)
    • NCEI Collection
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  • Weingartner, T. J. (2006) CTD cast data from 45 R/V Alpha Helix and R/V Wecoma Long-Term Observation Program (LTOP) cruises to the Coastal Gulf of Alaska from 1997-2004 as part of the U.S. GLOBEC program (NEP project). Biological and Chemical Oceanography Data Management Office (BCO-DMO). Dataset version 2006-12-04. https://doi.org/10.1575/1912/bco-dmo.2470.1
  • Parent ID (indicates this dataset is related to other data):
    • gov.noaa.nodc:BCO-DMO
Publication Dates
  • publication: 2013-10-27
  • revision: 2023-05-04
Data Presentation Form Digital table - digital representation of facts or figures systematically displayed, especially in columns
Dataset Progress Status Complete - production of the data has been completed
Historical archive - data has been stored in an offline storage facility
Data Update Frequency As needed
Supplemental Information
Acquisition Description:
Progress Report: April 1999
Project Title: The Gulf of Alaska GLOBEC LTOP Program
Investigators: Thomas Weingartner (PI), A. J. Paul (PI), Ken Coyle (PI), Lew Haldorson (PI), Dean Stockwell (PI), Terry Whitledge (PI), Jennifer Boldt, Seth Danielson, Alexei Pinchuk, and Amy Ruehs (All at University of Alaska), and Tom Royer (PI; Old Dominion Univ.)

The LTOP monitoring in the Gulf of Alaska completed its first year of sampling which included week-long cruises using the Alpha Helix in October 1997, and March, April, May, July, October, and December 1998. Sampling on all cruises included occupying stations along the Seward Line, which extends from the inner shelf to the edge of the continental slope. At each station CTD profiles and water samples for nutrients, chlorophyll and zooplankton nauplii were collected. Additional sampling includes MOCNESS tows at each of these stations with the tow depths chosen on the basis of backscatter from a 4- frequency, split-beam towed transducer array. The MOCNESS samples allow verification of the acoustical results and provide samples for species identification and additional analyses. The transducer is towed continually along the line and in conjunction with underway measurements of sea surface temperature, salinity, fluorescence and ADCP data provide data at very high spatial resolution. This standard sampling was supplemented during the July and October cruises with coincidental trawls from a charterd fishing vessel and surface gill nets from the Alpha Helix. We have also provided samples and/or sampling opportunities to other scientists for measurements of stable isotope composition of biota, dissolved carbon, bacteria, microzooplankton, seabird and marine mammal, and circulation.

The data suggest that the shelf is organized into three distinct dynamic and biological regimes. The innermost portion of the shelf consists of the Alaska Coastal Current, which is a high speed, persistent, dilute coastal current which is generally low in nutrients and chlorophyll. The inner shelf is segregated from the midshelf region by a salinity front. Nutrient concentrations, chlorophyll biomass, zooplankton, fish and seabird abundances appear to be consistently high just offshore of this front. However, it is not clear if this region of locally high biological productivity is associated with frontal processes or with the locally complicated bathymetry and coastline curvature. Over the midshelf region the circulation is weak and variable and biological abundances appear to be patchy in time and space. This region of the shelf often contains eddies having a diamter of ~50km. A third regime straddles the shelfbreak salinity front. Flow here is also swift (and often reflects shoreward movement of the Alaskan Stream) and nutrient, chlorophyll and zooplankton conentrations tend to be relatively high. Fish, seabird, and mammal abundances are also relatively high in this region. There is some suggestion that the vertebrate community structure here differs from that of the inner shelf.

Time permitting we augment the sampling along the Seward Line with additional alongshore transects. While these are relatively few in number they suggest that biological production is highly patchy owing perhaps to very complicated bathymetry.

The first year of sampling occurred during an El Nino year and the physical effects of this phenomenom included unusually warm (~1-2C above normal) and fresh (.15 psu) waters over the uper 200 m of the shelf. By summer, deep water temperatures were returning to normal and deep water salinities were above normal. The reason for the latter is not known but it implies either abnormally high upwelling rates or changes in the the composition of the offshore water masses that annually flow inshore. Higher salinities imply higher nutrient concentrations. However, it is not clear that changes in deep nutrient concentrations in the deep water on the shelf affect surface production.

Additional information about the GLOBEC LTOP in the Coastal Gulf of Alaska, including plots of cruise results, station locations, etc., can be obtained at: http://www.ims.uaf.edu/GLOBEC/

In this accession, NCEI has archived multiple versions of these data. The latest (and best) version of these data has the largest version number.
Purpose This dataset is available to the public for a wide variety of uses including scientific research and analysis.
Use Limitations
  • accessLevel: Public
  • Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.
Dataset Citation
  • Cite as: Weingartner, Thomas J. (2013). CTD cast data from 45 R/V Alpha Helix and R/V Wecoma Long-Term Observation Program (LTOP) cruises to the Coastal Gulf of Alaska from 1997-2004 as part of the U.S. GLOBEC program (NEP project) (NCEI Accession 0113922). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://www.ncei.noaa.gov/archive/accession/0113922. Accessed [date].
Cited Authors
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Acknowledgments
  • Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-0109078 Award URL: http://www.nsf.gov/awardsearch/showAward.do?AwardNumber=0109078
  • Funding provided by National Oceanic and Atmospheric Administration (NOAA) Award Number: unknown NEP NOAA
Theme keywords NODC DATA TYPES THESAURUS NODC OBSERVATION TYPES THESAURUS WMO_CategoryCode
  • oceanography
BCO-DMO Standard Parameters Global Change Master Directory (GCMD) Science Keywords Originator Parameter Names
Data Center keywords NODC COLLECTING INSTITUTION NAMES THESAURUS NODC SUBMITTING INSTITUTION NAMES THESAURUS Global Change Master Directory (GCMD) Data Center Keywords
Platform keywords NODC PLATFORM NAMES THESAURUS BCO-DMO Platform Names Global Change Master Directory (GCMD) Platform Keywords ICES/SeaDataNet Ship Codes
Instrument keywords NODC INSTRUMENT TYPES THESAURUS BCO-DMO Standard Instruments Global Change Master Directory (GCMD) Instrument Keywords Originator Instrument Names
Place keywords NODC SEA AREA NAMES THESAURUS Global Change Master Directory (GCMD) Location Keywords Provider Place Names
Project keywords NODC PROJECT NAMES THESAURUS BCO-DMO Standard Programs BCO-DMO Standard Projects Global Change Master Directory (GCMD) Project Keywords Provider Cruise IDs Provider Funding Award Information
Keywords NCEI ACCESSION NUMBER
Use Constraints
  • Cite as: Weingartner, Thomas J. (2013). CTD cast data from 45 R/V Alpha Helix and R/V Wecoma Long-Term Observation Program (LTOP) cruises to the Coastal Gulf of Alaska from 1997-2004 as part of the U.S. GLOBEC program (NEP project) (NCEI Accession 0113922). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://www.ncei.noaa.gov/archive/accession/0113922. Accessed [date].
Data License
Access Constraints
  • Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose.
Fees
  • In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media.
Lineage information for: dataset
Processing Steps
  • 2013-10-27T13:47:31Z - NCEI Accession 0113922 v1.1 was published.
  • 2023-05-04T07:17:31Z - NCEI Accession 0113922 was revised and v2.2 was published.
    Rationale: Updates were received for this dataset. These updates were copied into the data/0-data/ directory of this accession. These updates may provide additional files or replace obsolete files. This version contains the most complete and up-to-date representation of this archival information package. All of the files received prior to this update are available in the preceding version of this accession.
Output Datasets
Lineage information for: repository
Processing Steps
  • 2015-04-22T00:00:00 - NOAA created the National Centers for Environmental Information (NCEI) by merging NOAA's National Climatic Data Center (NCDC), National Geophysical Data Center (NGDC), and National Oceanographic Data Center (NODC), including the National Coastal Data Development Center (NCDDC), per the Consolidated and Further Continuing Appropriations Act, 2015, Public Law 113-235. NCEI launched publicly on April 22, 2015.
Acquisition Information (collection)
Instrument
  • CTD
Platform
  • R/V WECOMA
  • RV Alpha Helix
Last Modified: 2023-07-24T15:27:45Z
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