SATELLITE-DERIVED SEA-SURFACE TEMPERATURE DATA SETS FOR CLIMATE APPLICATIONS

Over the last few years there have been significant advances in the quality of data available from meteorological satellites. This has been especially true in the case of satellite-derived sea surface temperatures (SST). NOAA and NASA have implemented a ''Pathfinder Project'' aimed at re-analysing the vast archive of AVHRR data using carefully revised calibration coefficients. As a result of this activity there will soon be a long-term, consistent data set that is useful for climate applications. On the other side of the Atlantic the European Space Agency have launched the ERS-1 satellite which carries, as part of its payload, an improved infrared radiometer which has been specifically developed to measure sea surface temperature. This instrument, the Along Track Scanning Radiometer (ATSR), uses a dual view of the earth's surface to more accurately determine the atmospheric correction, has actively cooled detectors and includes two highly accurate on-board calibration targets. This instrument has a narrower swath than the AVHRR, and has been operating for less than three years, but the data quality is proving to be extremely good, and global data sets are now available to the research community. In conjunction with the improvements in space hardware and calibration techniques, there:is also considerable effort being applied to the development of new algorithms and analysis techniques which are giving more reliable SST data sets. The quality of these different data sets, the procedures used in their derivation, and their application to climate studies will be discussed.