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    • Inundation Mapping Tidal Surface - Mean Higher High Water

    Metadata Updated: March 15, 2024

    These data are a derived product of the NOAA VDatum tool and they extend the tool's Mean Higher High Water (MHHW) tidal datum conversion inland beyond its original extent.

    VDatum was designed to vertically transform geospatial data among a variety of tidal, orthometric and ellipsoidal vertical datums - allowing users to convert their data from different horizontal/vertical references into a common system and enabling the fusion of diverse geospatial data in desired reference levels (http://vdatum.noaa.gov/). However, VDatum's conversion extent does not completely cover tidally-influenced areas along the coast. For more information on why VDatum does not provide tidal datums inland, see http://vdatum.noaa.gov/docs/faqs.html.

    Because of the extent limitation and since most inundation mapping activities use a tidal datum as the reference zero (i.e., 1 meter of sea level rise on top of Mean Higher High Water), the NOAA Office for Coastal Management created this dataset for the purpose of extending the MHHW tidal datum beyond the areas covered by VDatum. The data do not replace VDatum, nor do they supersede the valid datum transformations VDatum provides. However, the data are based on VDatum's underlying transformation data and do provide an approximation of MHHW where VDatum does not provide one. In addition, the data are in a GIS-friendly format and represent MHHW in NAVD88, which is the vertical datum by which most topographic data are referenced.

    Data are in the UTM NAD83 projection. Horizontal resolution varies by VDatum region, but is either 50m or 100m. Data are vertically referenced to NAVD88 meters.

    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 February 29, 2024
    Metadata Created Date November 12, 2020
    Metadata Updated Date March 15, 2024
    Reference Date(s) 2019 (publication)
    Frequency Of Update asNeeded

    Metadata Source

    Harvested from NOS OCM

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Date February 29, 2024
    Metadata Created Date November 12, 2020
    Metadata Updated Date March 15, 2024
    Reference Date(s) 2019 (publication)
    Responsible Party NOAA Office for Coastal Management (Point of Contact, Custodian)
    Contact Email
    Guid gov.noaa.nmfs.inport:48104
    Access Constraints Cite As: Office for Coastal Management, [Date of Access]: Inundation Mapping Tidal Surface - Mean Higher High Water [Data Date Range], https://www.fisheries.noaa.gov/inport/item/48104., Access Constraints: None, Use Constraints: 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 -64.51
    Bbox North Lat 49.005
    Bbox South Lat 17.619
    Bbox West Long -124.851
    Coupled Resource
    Frequency Of Update asNeeded
    Harvest Object Id 9377c553-9e5b-47b2-af98-bdf3abff101b
    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": [[[-124.851, 17.619], [-64.51, 17.619], [-64.51, 49.005], [-124.851, 49.005], [-124.851, 17.619]]]}
    Progress completed
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 2007-10-01
    Temporal Extent End 2019-10-24

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