Article. Published in Marine Hydrophysical Journal. - 2011. - No4. - s. 3-12. The formation of the driving wind fields over the Black Sea is influenced by many physical factors. One of the most important is the monsoon mechanism associated with seasonal changes in the contrasts of buoyancy over the sea and the surrounding land. To isolate the effects caused by this mechanism, numerical experiments have been conducted and described on the sensitivity of the regional model of atmospheric circulation to changes in temperature contrasts between land and sea. It is shown that the effect of these effects is limited to the lower part of the atmosphere. These estimates of climatic perturbations allow us to describe the monsoon mechanism that determines the seasonal variability of the wind speed vorticity field and, as a result, the seasonal variability of large-scale water circulation in the Black Sea. Keywords: Black Sea, monsoon effect, climate, climate modeling.