The Hillarys Transect (2): Validation of satellite-derived sea surface temperature in the Indian Ocean off Perth, Western Australia

There has been a heightened interest in sea surface temperature (SST) measurements during the past two decades, particularly on a global scale, due largely to the advent of several El Nino episodes and increasing worldwide concern about global warming. Because of the continuous global measurements of SST that satellites can provide they play a fundamental role in acquiring the data sets necessary for studies of such climate processes. However, the satellite data still need to be validated against in situ measurements in order to assess the accuracy of satellite SST retrieval algorithms. Validation of such SST retrieval algorithms is the primary aim of the SST measurement program component of the Hillarys Transect. This paper describes a methodology for the validation of satellite-derived SST as well as the seasonal variation of SST off the coast of southern Western Australia. It discusses the factors which may affect the quality of in situ validation data and concludes that measurements of the bulk sea surface temperature (BSST) should be the preferred in situ data source for validation of satellite-based algorithms derived from floating buoy measurements. In this study BSST data possessed superior accuracy over the coincident radiometric sea surface skin temperature (SSST) data, and were found to be significantly better for validation purposes under wind speed conditions below 4ms-1.