Arctic Sea Level Since 1950
Abstract
We investigate sea level change and variability in the Arctic region over the 1950-2009 time span. Analysis of >60 long tide gauge records available since 1950 along the Norwegian and Russian sectors shows that coastal mean sea level was almost stable until about 1980 but since then displayed a clear increasing trend. In fact until the mid-1990s, the mean sea level closely followed the Arctic Oscillation (AO) index variations. However, since about 1995, the mea sea level curve departs from the AO influence and presents a large increasing trend of ~ 4 mm/yr. Using in situ ocean temperature data down to 700 m (from the WOD09 and JAMSTEC data bases), we estimated the thermosteric sea level at the tide gauge sites of the Norwegian sector and found that the recent increase in sea level has a dominant thermal origin. This suggests that inflow of warm North Atlantic waters may be responsible for the recent sea level changes observed along the Norwegian and Russian coasts. Comparison, over the altimetry era (since 1993), of altimetry-based and steric spatial trend patterns in sea level in the North Atlantic (>50°N) and Nordic Seas shows on the other hand that observed (altimetry-based) patterns essentially result from a combination of temperature and salinity effects, themselves driven by natural climate modes (AO and NAO).
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2011
- Bibcode:
- 2011AGUFM.G21B0816C
- Keywords:
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- 1641 GLOBAL CHANGE / Sea level change;
- 4207 OCEANOGRAPHY: GENERAL / Arctic and Antarctic oceanography