Abstract: Based on the onedimensional energy equations of the terrain, the IR field model was improved to be able to take various processes of the heat exchange among different parts of terrain into consideration. It was proved that the distribution of the surface soil temperatures obtained by the improved model is suitable in comparison with the experimental value. The IR radiation distribution for the natural terrain was calculated and agreement on the results from the model of distribution function of probability.

Key words: natural terrain, distribution function of probability, IR radiation field, natural terrain, distribution function of probability