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    • NOAA Office for Coastal Management Sea Level Rise Data: Current Mean Higher High Water Inundation Extent

    Metadata Updated: May 22, 2025

    These data were created as part of the National Oceanic and Atmospheric Administration Office for Coastal Management's efforts to create an online mapping viewer depicting potential sea level rise and its associated impacts on the nation's coastal areas. The purpose of the mapping viewer is to provide coastal managers and scientists with a preliminary look at sea level rise (slr) and coastal flooding impacts. The viewer is a screening-level tool that uses nationally consistent data sets and analyses. Data and maps provided can be used at several scales to help gauge trends and prioritize actions for different scenarios. The Sea Level Rise and Coastal Flooding Impacts Viewer may be accessed at: https://www.coast.noaa.gov/slr

    These data depict the potential inundation of coastal areas resulting from current Mean Higher High Water (MHHW) conditions. The process used to produce the data can be described as a modified bathtub approach that attempts to account for both local/regional tidal variability as well as hydrological connectivity. The process uses two source datasets to derive the final inundation rasters and polygons and accompanying low-lying polygons: the Digital Elevation Model (DEM) of the area and a tidal surface model that represents spatial tidal variability. The tidal model is created using the NOAA National Geodetic Survey's VDATUM datum transformation software (http://vdatum.noaa.gov) in conjunction with spatial interpolation/extrapolation methods and represents the MHHW tidal datum in orthometric values (North American Vertical Datum of 1988).

    The model used to produce these data does not account for erosion, subsidence, or any future changes in an area's hydrodynamics. It is simply a method to derive data in order to visualize the potential scale, not exact ___location, of inundation from sea level rise.

    Both raster and vector data are provided. The raster data represent both the horizontal extent of inundation and depth above ground, in meters. The vector data represent the horizontal extent of both hydrologically connected and unconnected inundation. The vector "slr" data represent inundation that is hydrologically connected to the ocean. The vector "low" data represent areas that are hydrologically unconnected to the ocean, but are below MHHW and may also flood.

    For more information, contact coastal.info@noaa.gov.

    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 May 15, 2025
    Metadata Created Date October 31, 2024
    Metadata Updated Date May 22, 2025
    Reference Date(s) 2023 (publication)
    Frequency Of Update asNeeded

    Metadata Source

    Harvested from NOS OCM

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Date May 15, 2025
    Metadata Created Date October 31, 2024
    Metadata Updated Date May 22, 2025
    Reference Date(s) 2023 (publication)
    Responsible Party NOAA Office for Coastal Management (Point of Contact, Custodian)
    Contact Email
    Guid gov.noaa.nmfs.inport:48105
    Access Constraints Cite As: Office for Coastal Management, [Date of Access]: NOAA Office for Coastal Management Sea Level Rise Data: Current Mean Higher High Water Inundation Extent [Data Date Range], https://www.fisheries.noaa.gov/inport/item/48105., Access Constraints: None, Use Constraints: These data illustrate the scale of potential flooding, not the exact ___location, and do not account for erosion, subsidence, or future construction. Inundation is shown as it would appear during the highest high tides (excludes wind driven tides) with the sea level rise amount. These data should be used only as a screening-level tool for management decisions. As with all remotely sensed data, all features should be verified with a site visit. The dataset is provided "as is," without warranty to its performance, merchantable state, or fitness for any particular purpose. The entire risk associated with the results and performance of this dataset is assumed by the user. This dataset should be used strictly as a planning reference and not for navigation, permitting, or other legal purposes., Distribution Liability: Any conclusions drawn from the analysis of this information are not the responsibility of the Office for Coastal Management or its partners.
    Bbox East Long -64.5
    Bbox North Lat 49.276
    Bbox South Lat -14.5
    Bbox West Long 144.5
    Coupled Resource
    Frequency Of Update asNeeded
    Harvest Object Id 42227793-55a5-411f-8337-bc93a89ebd93
    Harvest Source Id c0121fd9-df15-4168-ac04-42f6e36a794d
    Harvest Source Title NOS OCM
    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
    Metadata Language eng
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[144.5, -14.5], [-64.5, -14.5], [-64.5, 49.276], [144.5, 49.276], [144.5, -14.5]]]}
    Progress completed
    Spatial Data Service Type
    Spatial Reference System EPSG::4269
    Spatial Harvester True

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