A new physically based method for retrieving sea surface skin temperature (SST) from satellite measurements of upwelling infrared radiance is developed. The method accounts for atmospheric interference by utilizing multispectral window information to explicitly solve the radiative transfer equation. Two essential elements are required for this SST retrieval: (1) a priori specification of sea surface emissivity and reflectivity spectra and (2) atmospheric transmittances that accurately portray the relative spectral dependence of molecular absorption. The algorithm can be directly applied to any multispectral instrument (e.g., the NOAA advanced very high resolution radiometer and/or the ERS-1 along track scanning radiometer), as well as high resolution spectrometers such as the University of Wisconsin high-resolution interferometer sounder (HIS). Error analyses have shown that SST can theoretically be retrieved to within 0.22 K RMS using high spectral resolution data (or approximately 0.51 K RMS using broadband split-window data) provided that the a priori surface emissivity spectrum does not deviate by more than 0.005 from the true surface emissivity. High spectral resolution has distinct advantages in reducing the effects of atmospheric absorption and instrumental noise errors, as well as providing better guess atmospheric profiles for the transmittance calculations. Application of the method to HIS radiance data acquired from high-altitude aircraft during the 1993 Convection and Moisture Experiment and 1995 Ocean Temperature Interferometric Survey suggests the possibility of physical retrieval of SST from future satellite remote sensing systems (e.g., the EOS advanced infrared sounder) with accuracies limited primarily by detector performance. ¿ 1998 American Geophysical Union