A temperature error control technology for an operational satellite application system

The accuracy of satellite measured sea surface temperature(SST)is the key for both SSTalgorithms and applications,which is reported to reach 0.5℃.In fact,the accuracy of satellite measured SSTis affected by many factors,it is very difficult to obtain root mean square(RMS)error within 1℃ in an operational satellite SST application system.Many values of SST are found to be much lower than temperature measured by the ships in evaluating the accuracy of SSTderived from NOAA satellite data.The error distribution shows that larger negative values of temperature bias take up a high proportion with the maximum up to -17.2℃.Many patches of low temperature abnormality,distributing in the SST images,are caused by thin clouds or fogs,which may be mistakenly taken as eddy or front.The temperature abnormality is very difficult to be detected by SST inversion algorithm and cloud detection technology.A temperature error control technology is developed employing standard reference temperature images to detect the temperature abnormality.This method can efficiently detect the temperature abnor mality to remove the abnormal low values of SST and improve the accuracy of satellite measured SST.The RM Serror is improved from 5.71 to 1.75℃ in an operational SST system.It has been applied to drawing the fishery chart products of the North Pacific.