The role of satellite altimetry in gravity field modelling in coastal areas

During recent years altimetry from the two geodetic missions of GEOSAT and ERS-1 has enabled the derivation of high resolution near global gravity fie ld from altimetry [Andersen and Knudsen, 1995, 1996; Sandwell and Smith, 19 97]. Altimetric gravity fields are unique in the sense that they provide global uniform gravity information with very high resolution, and these global mar ine gravity fields are registered on a two by two minute grid corresponding to 4 by 4 kilometres at the equator. In this presentation several coastal complications in deriving the marine g ravity field from satellite altimetry will be investigated using the KMS98 gravity field. Comparison with other sources of gravity field information l ike airborne and marine gravity observations will be carried out and two fu ndamentally different test areas (Azores and Skagerak) will be studied to i nvestigated the different role of these different sources of gravity inform ation. (C) 2000 Elsevier Science Ltd. All rights reserved.