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    • BlueTopo

    Metadata Updated: April 13, 2025

    BlueTopo is a compilation of the nation's best available bathymetric data. Created as part of the NOAA Office of Coast Survey's nautical charting mission and its National Bathymetric Source (NBS) program, BlueTopo is curated bathymetric source data to provide a definitive nationwide model of the seafloor and navigational lakes. In the same way that a topographic map details the height of land, BlueTopo details the depth of lake beds and seafloor beneath navigationally significant U.S. waters.

    Primary sources of bathymetry in NBS compilations include NOAA and U.S. Army Corps of Engineers hydrographic surveys and topographic bathymetric (topo-bathy) lidar (light detection and ranging) data. Data submitted through the NOAA Office of Coast Survey's external source data process are also included. Coverage gaps in water over 200 meters are filled in BlueTopo through Global Multi-Resolution Topography, a merged model of bathymetry made available through Lamont-Doherty Earth Observatory. In addition to compiled bathymetry, BlueTopo contains metadata with quality metrics from the source data to enable the appropriate use of the product.

    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 March 28, 2025
    Metadata Created Date April 13, 2025
    Metadata Updated Date April 13, 2025
    Reference Date(s) May 14, 2021 (creation), (publication)
    Frequency Of Update continual

    Metadata Source

    Harvested from NOS OCS

    Other Data Resources

    Additional Metadata

    Resource Type Model
    Metadata Date March 28, 2025
    Metadata Created Date April 13, 2025
    Metadata Updated Date April 13, 2025
    Reference Date(s) May 14, 2021 (creation), (publication)
    Responsible Party Office of Coast Survey (Custodian)
    Contact Email
    Guid gov.noaa.nmfs.inport:75311
    Access Constraints Cite As: Office of Coast Survey, [Date of Access]: BlueTopo [Data Date Range], https://www.fisheries.noaa.gov/inport/item/75311., Access Constraints: Unrestricted, Use Constraints: Data use constraints for BlueTopo vary as it is derived from multiple source datasets. Please check the source data layer for specific data use constraints., Distribution Liability: Creative Commons - CC0-1.0
    Bbox East Long 60
    Bbox North Lat 75
    Bbox South Lat 0
    Bbox West Long 150
    Coupled Resource
    Frequency Of Update continual
    Harvest Object Id 93824e51-94ac-4c12-9db6-8370d42bd96c
    Harvest Source Id b7024f56-a531-4a4f-b381-12ebd50fe703
    Harvest Source Title NOS OCS
    Licence NOAA provides no warranty, nor accepts any liability occurring from any incomplete, incorrect, or misleading data, or from any incorrect, incomplete, or misleading use of the data. It is the responsibility of the user to determine whether or not the data is suitable for the intended purpose.
    Lineage BlueTopo is available for download as three layer GeoTIFFs with elevation, uncertainty, and raster attribute table (RAT) layers. All layers are presented as 32-bit floating point values. The bathymetry is compiled from multiple sources with varying quality and includes forms of interpolation. The bathymetric quality and interpolation is described through the vertical uncertainty layer and the associated data quality raster attribute table.
    Metadata Language eng
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[150.0, 0.0], [60.0, 0.0], [60.0, 75.0], [150.0, 75.0], [150.0, 0.0]]]}
    Progress onGoing
    Spatial Data Service Type
    Spatial Reference System EPSG::5703
    Spatial Harvester True
    Temporal Extent Begin 1807

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