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    • EK60 Water Column Sonar Data Collected During DY1703

    Metadata Updated: June 9, 2023

    Acoustic-Trawl Surveys of Walleye Pollock in the Gulf of Alaska (DY2017-03). The Midwater Assessment and Conservation Engineering (MACE) program of NOAA Fisheries, Alaska Fisheries Science Center (AFSC) conducted acoustic-trawl (AT) stock assessment surveys in the Gulf of Alaska (GOA) during the winter and early spring of 2017 to estimate the distribution and abundance of walleye pollock (Gadus chalcogrammus). The surveys were conducted aboard NOAA Ship Oscar Dyson, a 64 meter stern trawler equipped with acoustic and oceanographic instrumentation. The primary instrument for the survey was a Simrad EK60 split-beam echosounder system utilizing five frequencies (18, 38, 70, 120, and 200 kHz). The vessel departed Kodiak, Alaska on 14 March and surveyed Spruce Gully and inner Marmot Bay 14-15 March. The vessel returned to Kodiak for an unscheduled port call 15-17 March and departed Kodiak on 18 March. The Shelikof Strait survey was conducted 18-24 March followed by the Chirikof Shelfbreak survey 24-25 March. The outer Marmot Bay survey was conducted on 26 March. A sphere calibration of the echosounder system was conducted in Volcano Bay, Alaska on 14 February and at the end of the current cruise in Izhut Bay, Alaska on 27 March; no significant differences in gain parameters or transducer beam pattern characteristics were noted between the two calibrations. The vessel arrived at its homeport of Kodiak, Alaska on 27 March.

    Access & Use Information

    License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

    Downloads & Resources

    Dates

    Metadata Date September 14, 2021
    Metadata Created Date November 10, 2022
    Metadata Updated Date June 9, 2023
    Reference Date(s) March 14, 2017 (creation), April 2, 2018 (publication)
    Frequency Of Update notPlanned

    Metadata Source

    Harvested from NGDC MGG Sonar Water Column

    Other Data Resources

    Additional Metadata

    Resource Type Series
    Metadata Date September 14, 2021
    Metadata Created Date November 10, 2022
    Metadata Updated Date June 9, 2023
    Reference Date(s) March 14, 2017 (creation), April 2, 2018 (publication)
    Responsible Party NOAA National Centers for Environmental Information (Point of Contact)
    Contact Email
    Guid gov.noaa.ncei.wcd:DY1703_EK60
    Access Constraints Cite as: NOAA Alaska Fisheries Science Center. 2017. 'EK60 Water Column Sonar Data Collected During DY1703'. NOAA National Centers for Environmental Information. https://doi.org/10.25921/pj91-v451 [access date], 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., 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., Resource may not be available for up to one year after initial collection.
    Bbox East Long -151.58619
    Bbox North Lat 58.73756
    Bbox South Lat 55.42442
    Bbox West Long -157.00021
    Coupled Resource
    Frequency Of Update notPlanned
    Harvest Object Id 2a3d9d91-3de2-4401-bad1-681996b92526
    Harvest Source Id ab8b0290-e4db-4a00-89f2-4e427c2054b2
    Harvest Source Title NGDC MGG Sonar Water Column
    Licence These data are considered raw and have not been subjected to the NOAA's quality control or quality assurance procedures. They are released for limited public use as preliminary data to be used only with appropriate caution. NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty., Not subject to copyright protection within the United States.
    Lineage Calibrated w/o calibration data
    Metadata Language eng; USA
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-157.00021, 55.42442], [-151.58619, 55.42442], [-151.58619, 58.73756], [-157.00021, 58.73756], [-157.00021, 55.42442]]]}
    Progress completed
    Spatial Data Service Type
    Spatial Reference System urn:ogc:def:crs:EPSG::4326
    Spatial Harvester True
    Temporal Extent Begin 2017-03-14T14:48:37
    Temporal Extent End 2017-03-27T23:59:40

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