Comparison of new geoid models and EIGEN-2S in the North Atlantic region

A set of new gravity data, not previously available in the Nordic NKG data base, was obtained from NIMA. Based on existing gravity data and these additional data several different new geoids were estimated. The inclusion of the NIMA data set give local geoid changes of up to a few dm. The new CHAMP based EIGEN-2S geopotential model was compared to the EGM96 model using a two step procedure. Results from the two steps show that the EIGEN-2S geopotential model give better fit to GPS and MSSH/MDT data than EGM96 up to degree 50, but applying the full EGM96 model still gives the best resulting geoid.