Numerical simulations of air-pollutants in windy atmosphere

Spreading of gaseous pollutants in windy atmosphere is considered by means of numerical simulations of two-dimensional hydrodynamic equations. The parametric studies, which are performed for various magnitudes of a horizontal wind speed, reveal a plume development and a generation of vortices which occur as a result of Kelvin-Helmholtz instabilities. Mass density profiles exhibit high level of spatial and temporal variability. A spectral analysis of these profiles provides variable circular frequency and a wave number.