The Earth Gravitational Model 2008 (EGM2008), developed by the National Geospatial-Intelligence Agency (NGA), has been released. The model provides worldwide coverage of gravity data at 5’x5’ mean resolution with geoid accuracy of 15cm.
EGM2008 is constructed from a combination of GRACE satellite data, topographic data, altimetry on sea, and gravity observations on land areas. EGM2008 is developed up to degree/order 2160 with some additional terms up to degree/order 2190.The EGM2008 model coefficients and related products are freely available from the following Web site:
SOCET SET v5.5.0 supports the EGM2008 model using USG supplied grids of pre-computed geoid undulations at 1×1-minute resolution. The grid files translated into SOCET SET terrain file format are available for download from the GXP FTP site. Please contact your GXP customer support representative for instructions.