The need to estimate an influence of high sources to the air quality near the land surface by mathematical methods leads to the construction of models describing the processes of a polutants spreading in atmosphere. One peculiarity of this problem is the following. The source of a pollutant arranges on the height, where the horizontal component of wind velocity vector can take a large value. Therefore, the pollution spreads to the considerable distance before it reaches the lower layer of the atmosphere. Thereby, firstly, we have to consider a large domain for modeling this process. But we can not solve this problem using sufficiently small grid steps owing to computer possibilities. Secondly, the great interest is to study the features formed in concentration field as a result of influence of underlying surface. In this case, we often want to see a comprehensive scene in some small domain. An ordinary interpolation of modeling results obtained by using a large-step grid in the large domain apparently does not give us a probable enough scene.

In this paper, one of the approaches to solve this problem is considered.