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    • EK80 Water Column Sonar Data Collected During DY2002

    Metadata Updated: November 10, 2022

    The Midwater Assessment and Conservation Engineering (MACE) program of NOAA Fisheries, Alaska Fisheries Science Center (AFSC) conducted an acoustic-trawl (AT) stock assessment survey in the southeastern Aleutian Basin near Bogoslof Island during the winter of 2020 to estimate the distribution and abundance of walleye pollock (Gadus chalcogrammus). This survey was conducted aboard NOAA Ship Oscar Dyson, a 64 meter research stern trawler equipped with acoustic and oceanographic instrumentation. The primary acoustic instrument for the survey was a Simrad EK80 split-beam echosounder system utilizing six frequencies (18, 38, 70, 120, 200, and 333 kHz). The vessel departed Sand Point, Alaska on 17 February transiting toward the southeast Aleutian Basin. The survey was conducted 19-23 February, 2020, between 167 and 170 W longitude south of Bogoslof Island and north of Unalaska, Umnak Islands, and the Islands of Four Mountains. Research trawls were conducted in Shelikof Strait on 18 and 27 February and the vessel arrived in Kodiak, Alaska to end the cruise on 28 February. A calibration of the echosounder system was conducted at the beginning of the previous cruise on 12 February in Uganik Bay, Kodiak Island, Alaska.

    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.

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    Dates

    Metadata Date September 15, 2021
    Metadata Created Date November 10, 2022
    Metadata Updated Date November 10, 2022
    Reference Date(s) February 17, 2020 (creation), May 31, 2021 (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 15, 2021
    Metadata Created Date November 10, 2022
    Metadata Updated Date November 10, 2022
    Reference Date(s) February 17, 2020 (creation), May 31, 2021 (publication)
    Responsible Party NOAA National Centers for Environmental Information (Point of Contact)
    Contact Email
    Guid gov.noaa.ncei:DY2002_EK80
    Access Constraints Cite as: NOAA Alaska Fisheries Science Center. 2021. EK80 Water Column Sonar Data Collected During DY2002. NOAA National Centers for Environmental Information. https://doi.org/10.25921/4spx-ba23 [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 -152.124132007936
    Bbox North Lat 58.0193172270021
    Bbox South Lat 52.8411614953175
    Bbox West Long -169.916834913478
    Coupled Resource
    Frequency Of Update notPlanned
    Harvest Object Id 9ec5156b-9311-460e-acdd-a179c664577a
    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": [[[-169.916834913478, 52.8411614953175], [-152.124132007936, 52.8411614953175], [-152.124132007936, 58.0193172270021], [-169.916834913478, 58.0193172270021], [-169.916834913478, 52.8411614953175]]]}
    Progress completed
    Spatial Data Service Type
    Spatial Reference System urn:ogc:def:crs:EPSG::4326
    Spatial Harvester True
    Temporal Extent Begin 2020-02-17T00:00:00
    Temporal Extent End 2020-02-28T11:59:59

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