Water vapor and SST retrievals from ATSR data

Excerpts are presented from a longer version of a paper by C. Arulmani et al., in which radiosonde and standard atmospheric profiles were used to simulate 11 and 12 μm channel brightness temperatures at the satellite level using LOWTRAN-7 computer code. The effect of CO₂ is taken into account using standard atmospheres and with the exception of H₂O, the remaining gases in the atmospheres are treated as uniformly mixed and their effect is accounted for. From this the amount of water vapour was expressed in terms of the brightness temperature difference between the two view angles. Then the temperature equivalent absorption by water vapor was related to the total amount of water vapour. These parametric relations are used to retrieve water vapor and atmospherically corrected sea-surface temperature (SST) from the Along Track Scanning Radiometer (ATSR) data. In some places the water vapor compares well with that from the European Centre for Medium range Weather Forecasting (ECMWF). Also, for some regions sea-surface temperatures (SST) compare well with those produced by SADIST (Synthesis of ATSR Data Into Sea-surface Temperatures) computer code