OCEAN CLIMATE-CHANGE - COMPARISON OF ACOUSTIC TOMOGRAPHY, SATELLITE ALTIMETRY, AND MODELING

Comparisons of gyre-scale acoustic and direct thermal measurements of heat content in the Pacific Ocean, satellite altimeter measurements of sea surface height, and results from a general circulation model show that only about half of the seasonal and year-to-year changes in sea level are attributable to thermal expansion. Interpreting climate chan ge signals from fluctuations in sea Level is therefore complicated. Th e annual cycle of heat flux is 150 +/- 25 watts per square meter (peak -to-peak, corresponding to a 0.2 degrees C vertically averaged tempera ture cycle); an interannual-change of similar magnitude is also detect ed. Meteorological estimates of surface heat flux, if accurate, requir e a Large seasonal cycle in the advective heat flux.