RAINWATER POLLUTION BY ATMOSPHERIC AIR TAKING INTO ACCOUNT THE PROBABLE NATURE OF METEOROLOGICAL CONDITIONS

The article is devoted to the problem of surface water pollution by pollutants contained in the atmospheric air and getting into water bodies as a result of rainfall and subsequent surface runoff. The authors propose a general scheme of the corresponding calculation for simplified conditions: one source of atmospheric air pollution of constant power, no vertical wind and no background pollution. The calculation scheme consists of three blocks: development of an algorithm for calculating the concentration field of pollutants in the air; determination of the concentration of pollutants in rainwater; accounting for meteorological conditions. It is proposed to calculate the concentration field of a substance in the air for fixed values of wind speed and direction by numerically integrating the turbulent diffusion equation for a stationary case. The corresponding calculation formula is given. To calculate rainwater pollution for fixed horizontal coordinates, the absorption intensity function is introduced into consideration, which generally assumes both physical and chemical absorption. Finally, the mass of the substance getting into the water body is calculated by integrating over the entire catchment area. It is proposed to consider adverse meteorological conditions using the method of statistical tests (the Monte Carlo method). The advantage of this method is that it belongs to non-parametric methods of mathematical statistics, which do not require information on the principle of probability distribution of the random variables under consideration and their functions. Reference data, in particular, the state standard of Ukraine "Building Climatology", can be used as initial data for determining the probability distribution function of wind speed and direction. The obtained distribution functions allow modeling the probability distribution of the pollutant mass entering a water body with rainwater. The developed calculation scheme allows determining the pollution of a water body under the most adverse meteorological conditions.