U.S. North-South Deflections (DEFLEC96)

Metadata Updated: October 13, 2020

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.

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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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Metadata Date September 25, 2017
Metadata Created Date October 13, 2020
Metadata Updated Date October 13, 2020
Reference Date(s) January 1, 1999 (publication)
Frequency Of Update irregular

Metadata Source

Harvested from NGDC MGG Geophysics

Additional Metadata

Resource Type Dataset
Metadata Date September 25, 2017
Metadata Created Date October 13, 2020
Metadata Updated Date October 13, 2020
Reference Date(s) January 1, 1999 (publication)
Responsible Party NOAA National Centers for Environmental Information (Point of Contact)
Contact Email
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
Guid gov.noaa.ngdc.mgg.geophysics:G01442
Harvest Object Id c370df9d-e969-431b-8ccd-345933793588
Harvest Source Id 7dfdabdf-e8e7-43e8-881a-ae4d7b994a7a
Harvest Source Title NGDC MGG Geophysics
Metadata Language
Metadata Type geospatial
Progress completed
Spatial Data Service Type
Spatial Reference System urn:ogc:def:crs:EPSG::5715
Spatial Harvester True

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