Spectral Analysis of Mean Dynamic Ocean Topography From the GRACE GGM01 Geoid

Abstract

With the development of the satellite gravity missions and the satellite altimetry missions, there have been recent improvements in geoid models and sea surface height (SSH) models, so now one can compute more accurate dynamic ocean topography (DOT). In this study, we computed a new mean DOT using a new geoid model (GGM01C) from GRACE and an improved mean SSH model (KMSS04) from a decade of multi-satellite altimetry. And DOT is computed using the GGM01C and EGM96 model to access the improvements and differences between these two geoid models. We find that the DOT is composed of long waves mainly, medium waves partially and short waves scarcely, and that the zonal spectrum of the DOT is different from its meridional spectrum. The differences in the DOTs from GGM01C and EGM96 in the test area indicate that great differences exist in these two gravity models, at least in equatorial area.