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    • U.S. North-South Deflections (DEFLEC96)

    Metadata Updated: December 3, 2021

    This 2' surface deflection of the vertical grid for the conterminous United States is the DEFLEC96 model. The computationused about 1.8 million terrestrial and marine gravity data held in the National Geodetic Survey gravity data base in July 1996. These data were augmented by gravity data contributions from NGA (former National Imagery and Mapping Agency (former Defence Mapping Agency)). The deflections were obtained by numerical differentiation of cubic spline models along the meridians of the GEOID96 grid. The gravity values are based on theInternational Gravity Standardization Net 1971 (IGSN71). The deflections are referred to the Geodetic Reference System 1980 (GRS80) ellipsoidal normals. The deflections of the vertical incorporate the reference system relationship between NAD 83(86) and ITRF94(1996.0), the datum offset of NAVD 88, and thecontributions from 2951 GPS on leveled benchmarks. The curvature of the plumb line correction has been applied. http://www.ngs.noaa.gov/DEFLEC/deflec.html We are particularly grateful to NGA (former National Imagery and Mapping Agency) for their assistance and their data contributions.

    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 September 25, 2017
    Metadata Created Date December 3, 2021
    Metadata Updated Date December 3, 2021
    Reference Date(s) January 1, 1999 (publication)
    Frequency Of Update irregular

    Metadata Source

    Harvested from NGDC MGG Geophysics

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Date September 25, 2017
    Metadata Created Date December 3, 2021
    Metadata Updated Date December 3, 2021
    Reference Date(s) January 1, 1999 (publication)
    Responsible Party NOAA National Centers for Environmental Information (Point of Contact)
    Contact Email
    Guid gov.noaa.ngdc.mgg.geophysics:G01442
    Access Constraints 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 Constraints: If you use this data, please cite the National Geophysical Data Center and the originator of the data., Access Constraints: None
    Bbox East Long -66
    Bbox North Lat 53
    Bbox South Lat 24
    Bbox West Long -130
    Coupled Resource
    Frequency Of Update irregular
    Harvest Object Id 84ff6752-6718-421c-9209-94b6ae16e5fc
    Harvest Source Id 80dfcf5d-5e08-457e-83e4-cfc696e378bc
    Harvest Source Title NGDC MGG Geophysics
    Licence
    Metadata Language eng; USA
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-130.0, 24.0], [-66.0, 24.0], [-66.0, 53.0], [-130.0, 53.0], [-130.0, 24.0]]]}
    Progress completed
    Spatial Data Service Type
    Spatial Reference System urn:ogc:def:crs:EPSG::5715
    Spatial Harvester True

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