A cloud-free, satellite-derived, sea surface temperature analysis for the West Florida Shelf

Abstract

Clouds are problematic in using Advanced Very High Resolution Radiometer (AVHRR) imagery for describing sea surface temperature (SST). The Tropical Rainfall Measuring Mission Microwave Imager (TMI) observes SST through clouds, providing daily, 1/4° maps under all weather conditions excepting rain. A TMI limitation, however, is coarse resolution. Optimal interpolation (OI) is used to generate a cloud-free, 5-km, daily SST analysis for the West Florida Shelf (WFS) by merging the high-resolution (cloud-covered) AVHRR with the coarse-resolution (cloud-free) TMI SST products. Comparisons with in-situ data show good agreements. Given large spatial gradients by coastal ocean processes, this regional analysis has advantage over the global, weekly, 1° Reynolds SST. A 5-year (1998-2002) OI SST analysis is diagnosed using Empirical Orthogonal Functions. The first two modes represent annual cycles, one by surface heat flux and another by shelf circulation dynamics.