A global Mean Dynamic Topography and Ocean Circulation Estimation using GOCE Gravity Models
Abstract
The Gravity and steady state Ocean Circulation Explorer (GOCE) satellite mission measures Earth's gravity field with an unprecedented accuracy at short spatial scales. Preliminary results have already demonstrated a significant advance in our ability to determine the ocean's general circulation. The improved gravity model provided by the GOCE mission has enhanced the resolution and sharpened the boundaries of those features compared with earlier satellite only solutions. In this study, more recent gravity models from GOCE are combined with the DTU10MSS mean sea surface to construct a global mean dynamic topography (MDT) model. Calculation of the geostrophic surface currents from the MDT reveals improvements for all of the ocean's major current systems. Furthermore, the finer scale features, such as eddies, meanders and branches of the current system are visible. Regional variations in mean sea level as mapped by satellite altimetry may also provide information about changes in the surface geostrophic mean circulation. Changes in the geostrophic ocean currents will have an impact on both the volume and the heat transport in the oceans which, in turn, will have an impact on the local environment and climate. A preliminary analysis of such effects has been carried out using the GOCE MDT. One example is the increasing sea level south of Greenland which signals a slow down in the North Atlantic sub-polar gyre. The results of this preliminary analysis, further demonstrate the potential of the GOCE mission in Earth sciences.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2011
- Bibcode:
- 2011AGUFM.G41C..02K
- Keywords:
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- 1222 GEODESY AND GRAVITY / Ocean monitoring with geodetic techniques