Determination of land surface temperature distributions from single channel IR measurements: an effective spatial interpolation method for the use of TOVS, ECMWF and radiosonde profiles in the atmospheric correction scheme

Abstract

For the determination of land surface temperatures from brightness temperature measurements in a single infrared channel, as for instance taken by the Advanced Very High Resolution Radiometer (AVHRR) or Meteosat, an explicit correction of the atmospheric influence is necessary. Therefore, the vertical and horizontal distribution of temperature and humidity has to be known. Possible sources for these atmospheric profiles are TOVS measurements, the ECMWF analysis and radiosonde data. These sources provide the information discretely in space and time and are particularly characterized by large differences in horizontal resolution. This paper presents a method that overcomes the problems arising from the different spatial sampling. Furthermore, some case studies with AVHRR infrared measurements will be presented and atmospheric corrections based on TOVS, ECMWF and radiosonde profiles will be intercompared.