Journal of Geodesy

, Volume 88, Issue 8, pp 765–771 | Cite as

Slope correction for ocean radar altimetry

  • David T. SandwellEmail author
  • Walter H. F. Smith
Original Article


We develop a slope correction model to improve the accuracy of mean sea surface topography models as well as marine gravity models. The correction is greatest above ocean trenches and large seamounts where the slope of the geoid exceeds 100 \(\upmu \)rad. In extreme cases, the correction to the mean sea surface height is 40 mm and the correction to the along-track altimeter slope is 1–2 \(\upmu \)rad which maps into a 1–2 mGal gravity error. Both corrections are easily applied using existing grids of sea surface slope from satellite altimetry.


Radar altimetry Ocean circulation  Marine gravity 



The CryoSat-2 and Envisat data were provided by the European Space agency, and NASA/CNES provided data from the Jason-1 altimeter. This research was supported by ConocoPhillips, the National Science Foundation (OCE-1128801), the Office of Naval Research (N00014-12-1-0111) and the National Geospatial-Intelligence Agency (HM0177-13-1-0008). The manuscript contents are the opinions of the authors and the participation of W. H. F. Smith should not be construed as indicating that the contents of the paper are a statement of official policy, decision, or position on behalf of NOAA or the US Government.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Scripps Institution of OceanographyLa JollaUSA
  2. 2.NOAA Laboratory for Satellite AltimetryCollege ParkUSA

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