Regional characteristics of long-term sea level variations from satellite altimetry and tide gauges

TOPEX/POSEIDON and JASON-1 sea level observations over the most recent 12 years have qualitatively been used to study regional characteristics in sea level variations over this period. EOFs of annual anomalies have been derived using different periods of time and compared. Furthermore, spatial characteristics have been derived for sea level slopes computed over different time intervals. Finally, Tide gauge data have been analyzed to derive spatio-temporal characteristics of sea level variations. Finally, correlations between long-term changes in sea level and sea surface temperature have been analyzed to deduce the steric contribution to sea level change. Consistent increases in both sea level and sea surface temperatures are found in most parts of the Atlantic Ocean over this period. In the Indian Ocean and particularly the Pacific Ocean, the trends in both sea level and temperature are still dominated by the large changes associated with the large El Ninõ Southern Oscillation in 1997-1998.