NODC Standard Product: US Navy Geosat Enhanced JGM-3 Geophysical Data Records (GDR) from the Geodetic and Exact Repeat Missions (NODC Accession 0053056)

This accession contains a copy of the NODC CD_ROM product titled 'Enhanced JGM-3 Geophysical Data Records (GDRs) from the Geodetic and Exact Repeat Missions' that was released in June 1997. The original ten CD-ROM set and documentation were compiled by John Lillibridge and Bob Cheney at Laboratory for Satellite Altimetry (LSA), Center for Satellite Applications and Research (STAR), NOAA. Parameters include: time, orbit, latitude/longitude, and sea surface height. Corrections to the data include: sea level, wind and wave data, tides, dry and wet troposphere, ionosphere and height bias. The data are in binary format.

This June 1997 release of satellite altimeter data collected by the U.S. Navy's Geosat mission represents a significant improvement over previous versions. The ten CD ROMs contain geophysical data records which span both the Geodetic Mission (GM: 3/85 - 9/86) and Exact Repeat Mission (ERM: 11/86 - 12/89). The GDRs incorporate a new 10-cm satellite orbit computed by the NASA Goddard Space Flight Center using the JGM-3 gravity model. In addition, the overall accuracy of the data was increased by new geophysical corrections (CSR 3.0 tides; model troposphere from the NCEP/NCAR reanalysis; IRI95 ionosphere; a new sea state bias based on wind, wave and satellite attitude; and corrections for clock drift and timing bias).

In version 2, data have been converted into Climate and Forecast (CF) compliance Network Common Data Form (NetCDF) by Satellite Oceanography Group at the NODC.