Global sea level (SL) has undergone a rising trend for at least a century; its cause is believed to be unrelated to climate change [1]. We observe,however, that fluctuations (anomalies) from a linear SL rise show a pronounced anti-correlation with global average temperature--and even more so with tropical average sea surface temperature. We also find a suggestive correlation between negative sea-level rise anomalies and the occurrence of El Nino events. These findings suggest that--under current conditions-- evaporation from the ocean with subsequent deposition on the ice caps, principally in the Antarctic, is more important in determining sea-level changes than the melting of glaciers and thermal expansion of ocean water. It also suggests that any future moderate warming, from whatever cause, will slow down the ongoing sea-level rise, rather than speed it up. Support for this conclusion comes from theoretical studies of precipitation increases [2] and from results of General Circulation Models (GCMs) [3,4]. Further support comes from the (albeit limited) record of annual ice accumulation in polar ice sheets [5].

References:

1. A. Trupin and J. Wahr. Geophys J. Int., 100, 441-453 (1990)

2. D. Bromwich. "Ice sheets and sea level" Nature, 373, 18 (1995)

3. S.L. Thompson, and D. Pollard. Eos 76, No. 46 Suppl.(1995); J. Clim. (1997)

4. H. Ye and J.R. Mather, Int. J. Climatol., 17, 155-162 (1997)

5. D.A. Meese et al., Science 266, 1680-1682 (1994)