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Toward Improved Estimation of the Dynamic
Topography and Ocean Circulation in the High Latitude
and Arctic Ocean: The Importance of GOCE
J. A. Johannessen
R. P. Raj
J. E. Ø. Nilsen
T. Pripp
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P. Knudsen
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F. Counillon
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D. Stammer
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L. Bertino
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O. B. Andersen
N. Serra
N. Koldunov
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Received: 22 March 2013 / Accepted: 26 November 2013 / Published online: 23 January 2014
The Author(s) 2014. This article is published with open access at Springerlink.com
Abstract The Arctic plays a fundamental role in the climate system and shows signifi-
cant sensitivity to anthropogenic climate forcing and the ongoing climate change. Accel-
erated changes in the Arctic are already observed, including elevated air and ocean
temperatures, declines of the summer sea ice extent and sea ice thickness influencing the
albedo and CO
2
exchange, melting of the Greenland Ice Sheet and increased thawing of
surrounding permafrost regions. In turn, the hydrological cycle in the high latitude and
Arctic is expected to undergo changes although to date it is challenging to accurately
quantify this. Moreover, changes in the temperature and salinity of surface waters in the
Arctic Ocean and Nordic Seas may also influence the flow of dense water through the
Denmark Strait, which are found to be a precursor for changes in the Atlantic meridional
overturning circulation with a lead time of around 10 years (Hawkins and Sutton in
Geophys Res Lett 35:L11603,
2008
). Evidently changes in the Arctic and surrounding seas
have far reaching influences on regional and global environment and climate variability,
thus emphasizing the need for advanced quantitative understanding of the ocean circulation
and transport variability in the high latitude and Arctic Ocean. In this respect, this study
combines in situ hydrographical data, surface drifter data and direct current meter mea-
surements, with coupled sea ice-ocean models, radar altimeter data and the latest GOCE-
based geoid in order to estimate and assess the quality, usefulness and validity of the new
GOCE-derived mean dynamic topography for studies of the ocean circulation and transport
estimates in the Nordic Seas and Arctic Ocean.
