Arctic Marine Gravity

A New Arctic Marine Gravity Field from ERS-1 and ERS-2 Data


Click on the thumbnail for high resolution GIF images.

This work is done in collaboration with Dr. Seymour Laxon of University College London, Mullard Space Science Laboratory; it involves the derivation of marine gravity from satellite altimetry over permanently ice-covered polar seas.

NEW Arctic Ocean Gravity

This image shows the marine gravity field over the Arctic Ocean as determined using radar altimetry acquired from ESA's ERS-1 and ERS-2 satellites over seas which are perpetually ice-covered . Previously data over ice covered regions has been excluded due to contamination by sea ice. This contamination is mitigated by the reprocessing of "raw", ERS waveform data done at MSSL. This new field has an accuracy of 3 to 4 mGal in most regions of the Arctic and a resolution of about 20 km. Improved algorithms were used. This new field was submitted to the international Arctic Gravity Project (ArcGP) and is being presented at the European Geophysical Society's XXVI General Assembly in Nice, France, March 2001. The field is now available and be accessed by anonymous ftp. (contact Dave McAdoo at or Seymour Laxon at These data reveal both known and unknown features on the floor of the Arctic Ocean. The new discoveries include an extinct spreading ridge in the ocean basin north of Canada revealing for the first time, the origin of a large part of the Arctic Basin, a result of major geophysical significance. To see a discussion of our previous Arctic and Antarctic marine gravity fields from ERS-1

For details see an article by Laxon and McAdoo in the July 29, 1994 issue of Science, volume 265, pp 621-624, or see Laxon and McAdoo, 1998, Satellites Provide New Insights into Polar Geophysics, EOS, Transactions AGU, 79 (6), 69-72.

For more information contact Dave McAdoo at or Seymour Laxon at

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