The determination of the Sea Surface Temperature (SST), as well as the Land Surface Temperature (LST), is typically achieved through the algorithm called Split Windows (SW). This method is compatible with detectors whose Noise Equivalent Delta Temperature (NEDT) is on the order of 0.1 °K or less. The method increases the observation error by a factor of 4 or 5 on the SST determination. The NEDT of un-cooled micro-bolometers detectors (used in small and medium satellites) is in the range of 0.5°K to 1.5°K. To achieve a SST error less than 0.7°K it is necessary to search for other algorithms. In [1] an alternative method is presented, but in this work a new algorithm is presented, based on the theory of perturbations and stochastic process, compatible with the new generation of areal micro-bolometer detector, that allows one to meet the accuracy requirement.