Based on the climatic picture of circulation the problem of modeling the dissolved methane in the Arctic Ocean with a drain of the Siberian Rivers is considered. The regional large-scale ocean model, developed in the ICM&MG, SB RAS is used. The distribution of the dissolved methane in the sea water is obtained with the advection-diffusion equation with parameterization of the oxidation process included.
As a result of numerical modeling accumulation processes and stability with respect to time of high concentration of the dissolved methane in the Laptev Sea, known from the observational data are reproduced. It is obtained that the drain of the Lena River can bring a powerful contribution to an abnormal high concentration of methane in the Dm. Laptev Strait water. It is shown that methane oxidation controls the CH4 release in the atmosphere.