Results of One Year of Preoperational Production of Sea Surface Temperatures from<i>GOES-8</i>

Abstract

Routine calculations of sea surface temperatures (SSTs) from Geostationary Operational Environmental Satellite-8 (GOES-8, also known as GOES-East) data have been made at the Centre de Météorologie Spatiale (CMS) of Météo-France on an hourly basis since October 1999. This work is a first step toward increasing the coverage of the Atlantic through combined use of GOES-East and the Meteosat Second Generation (MSG) satellite system. SST calculations have been made using coefficients derived from regressions applied on simulated brightness temperatures. Validations with drifting buoy observations showed that the vicinity of the cloud mask has a significant impact on the results and that the accuracies obtained for the cloud-free validation boxes are comparable to those of the Advanced Very High Resolution Radiometer (AVHRR) with standard deviation of the differences relative to buoy observations of about 0.6 K by day and 0.4 K by night. An analysis of the retrieval error as a function of time of day revealed that few data are available around the local noon and midnight, due to the drifting buoys' data transmission schedule. The diurnal cycle has thus been analyzed using measurements by moored buoys transmitting data via geostationary satellites. A 0.3-K amplitude has been found for the diurnal cycle. Comparison with best-fit coefficient results concluded that the simulation-derived coefficients have almost reached the optimum level that can be achieved with the corresponding algorithms.