Modal Bias in Sea Level and Sea Surface Temperature, with Applications to Remote Sensing

Abstract

From vertical normal mode decomposition, sea level and sea surface temperature (SST) are shown to be modally biased?higher modes are suppressed in sea level while lower modes are suppressed in SST data. Having been effectively ?low passed? and ?high passed? (with respect to mode number) by nature, sea level and SST contain complementary information which can in principle be combined to yield a relatively unbiased picture. The full potential of the sea level-SST pair is not appreciated in present remote sensing studies, where the two are used separately. A proposed ?stereoscopic? method may in the future produce unbiased three-dimensional pictures from satellite-sensed two-dimensional pictures of sea level and SST. Modal bias in coastal trapped waves is studied in the Appendix.