Determination of temperature by remote sensing

The knowledge of land surface temperature (LST) is of great importance, because it helps us to understand processes such as energy exchange between surface and atmosphere, water requirements in agricultural soils, control and prevention of fires and the evolution of climate change. Also, we need to try to know its value with enough accuracy. Two important factors are taken into account: the surrounding environmental conditions on the surface and its own emissivity. When performing a measurement of the LST, two types of corrections should be applied: first, the atmospheric correction in order to eliminate its contribution to the satellite measurements and a second one due to the effect of surface emissivity when the measurement is done both from satellite and in the field. This work presents an exhaustive review of the methodology currently used to perform both corrections. In the case of surface emissivity, the techniques known to determine it and the methodologies used for its correction will be shown. For atmospheric correction, two widely contrasted methods are exposed: the single-channel method and the differential absorption of the split-window method, which avoid the need for radiosoundings, in order to correct the radiative effect of the atmosphere. The knowledge of the methodology shown can be of help for any study of the LST, either from satellite or on ground level.