The aim of this paper is to improve the atmospheric correction process for monitoring the sea surface temperature (SST) around the outfall of a nuclear power plant in southern Taiwan. Field experiments collecting radiosonde data and ship-measured SST were taken concurrently with Landsat Thematic Mapper (TM) observations. Some auxiliary methods were applied to register the geometric locations and to estimate the atmospheric effects, such as the dynamic location method, error weighting and the gamma factor. Meanwhile, the accuracy of LOWTRAN used for atmospheric effect adjustments was discussed. Another field experiment was used as an independent data set to evaluate the atmospheric effect and the SST estimated with this process. Comparison between the ship-measured and satellite estimated SST reveals that the root mean square error (RMSE) will lessen from about 8 degrees C if the atmospheric effect was neglected to about 1.3 degrees C if the atmospheric correction process of this study is applied.