A study has been carried out using MODTRAN 3.5 simulations of the Along Track Scanning Radiometer 2 (ATSR-2) data at 3.7, 11, and 12 ¿m wavelengths to give a range of algorithms for estimating surface. Making use of the dual-angle feature of the ATSR-2, algorithms based on dual-angle, split-window, and mixed structure have been considered. The coefficients of the algorithms are derived by regression analysis using the MATLAB code. The evaluation of the sensitivity of each algorithm shows that in general, dual-angle algorithms provide smaller errors in the estimation of surface temperature than the split-window algorithms and that the algorithms with water vapor dependence give an improvement in the accuracy of the results. Finally, a validation for a homogenous test site in Australia under conditions of low atmospheric water vapor content is included; the results show a root-mean-square deviation lower than 1.8 K for split-window algorithms and 1.4 K for dual-angle algorithms.