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    • Global monthly climatology of deep sound channel axis, sonic layer depth, and other underwater acoustic parameters, total of 14, derived from World Ocean Atlas 2018 (NCEI Accession 0208105)

    Metadata Updated: April 1, 2025

    This dataset contains global monthly climatology of sonic layer depth, surface sound speed, and other underwater acoustic parameters, total of 14, derived from World Ocean Atlas 2018 profile data. Data are partitioned into 12 monthly and annual mean files. Acoustics is most effective in undersea detection, localization, and communication. However, there is no global climatology of underwater acoustic parameters. A multiple gradient method is used to analyze the sound speed profile, which is calculated from temperature and salinity profiles using the Thermodynamic Equation of Seawater-2010 (TEOS-10) to get the sonic layer depth (SLD), deep sound channel (DSC) axis depth, and second sound channel (SSC) axis depth from the gridded (0.25 degree, and 1 degree) temperature and salinity fields of the National Centers for Environmental Information (NCEI) world ocean atlas 2018. With the given (SLD, DSC axis depth, SSC axis depth), the other acoustic parameters are calculated such as sound speed at the surface, sound speed at the SLD, sound speed at the DSC axis, sound speed at the SSC axis, minimum cut-off frequency, in-layer gradient, below-layer gradient, surface duct cut-off frequency, deep sound channel strength, critical depth of the DSC, depth excess, and second sound channel strength. Data are in netcdf.

    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 2025-02-21T13:10:17Z
    Metadata Created Date July 2, 2021
    Metadata Updated Date April 1, 2025
    Reference Date(s) December 18, 2019 (publication)
    Frequency Of Update asNeeded

    Metadata Source

    Harvested from NOAA/NESDIS/ncei/accessions

    Other Data Resources

    Graphic Preview

    Preview graphic

    Additional Metadata

    Resource Type Dataset
    Metadata Date 2025-02-21T13:10:17Z
    Metadata Created Date July 2, 2021
    Metadata Updated Date April 1, 2025
    Reference Date(s) December 18, 2019 (publication)
    Responsible Party (Point of Contact)
    Contact Email
    Guid gov.noaa.nodc:0208105
    Access Constraints Cite as: Chu, Peter C; Fan, Chenwu (2019). Global monthly climatology of deep sound channel axis, sonic layer depth, and other underwater acoustic parameters, total of 14, derived from World Ocean Atlas 2018 (NCEI Accession 0208105). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/2x35-sc93. Accessed [date]., 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.
    Bbox East Long 180
    Bbox North Lat 90
    Bbox South Lat -90
    Bbox West Long -180
    Coupled Resource
    Frequency Of Update asNeeded
    Graphic Preview Description Preview graphic
    Graphic Preview File https://www.ncei.noaa.gov/access/metadata/landing-page/bin/gfx?id=gov.noaa.nodc:0208105
    Graphic Preview Type PNG
    Harvest Object Id 37587e4d-70b3-4972-8afb-218910893e5b
    Harvest Source Id c084a438-6f6b-470d-93e0-16aeddb9f513
    Harvest Source Title NOAA/NESDIS/ncei/accessions
    Licence accessLevel: Public
    Lineage
    Metadata Language eng
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-180.0, -90.0], [180.0, -90.0], [180.0, 90.0], [-180.0, 90.0], [-180.0, -90.0]]]}
    Progress completed
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 1950-01-01
    Temporal Extent End 2018-12-31

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