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On Estimating the Dynamic Ocean Topography – A Profile Approach

  • W. BoschEmail author
  • R. Savcenko
Conference paper
Part of the International Association of Geodesy Symposia book series (IAG SYMPOSIA, volume 135)

Abstract

Since the essential improvements of GRACE gravity field models reliable signatures of the dynamic ocean topography (DOT) can be obtained by subtracting geoid heights from the sea surface. The differences are usually performed after an initial data gridding of sea surface heights implying already an undesirable loss of signal. On the other hand, even the latest gravity field solutions from GRACE exhibit a meridional striping in the geoid and require a smoothing. In order to preserve the high along-track resolution of altimetry the present paper investigates a profile approach which (i) performs a spectral smoothing of the GRACE gravity field (ii) merges mean-tide geoid profiles to the along-track sea level measurements of satellite altimetry and (iii) performs a common low pass filtering of along-track differences in order to make filtered sea level and geoid heights spectrally consistent. The approach is performed with the latest GRACE-only gravity field models and the sea surface height profiles of TOPEX and Jason-1 and produces time varying profiles of the DOT. Globally, the profiles exhibit the expected topographic features which are compared with independent estimates of the DOT.

Keywords

Gravity Field Satellite Altimetry Geoid Height Gravity Field Model Geoid Undulation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  1. 1.Deutsches Geodätisches Forschungsinstitut (DGFI)MünchenGermany

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