Improving the geoid: Combining altimetry and mean dynamic topography in the California Coastal Ocean
Event: 2014 Ocean Surface Topography Science Team Meeting
Session: The Geoid, Mean Sea Surfaces and Mean Dynamic Topography
Presentation type: Type Poster
Contribution: PDF file
Satellite gravimeters and altimeters together allow the Earth's geoid to be mapped with an accuracy of order 1 m. To achieve greater accuracy than this requires knowledge of the dynamic ocean topography. In this study two dynamic ocean topographies are considered for the region of the California Current System: one is derived from an assimilating model (a regional version of ECCO) and the second is from AVISO. Both dynamic ocean topographies have accuracies of order 10 cm. They are used to solve for a geoid correction, in order to improve the overall consistency between the assimilated ocean model and along-track altimetric observations in the region. The correction is as large as the dynamic ocean topography, with a magnitude of 15 cm and significant structure, especially near the coast. While the improvement in the consistency is modest, it offers evidence that high-resolution dynamic ocean topography products can be used to correct estimates of the geoid.