Effects of Pollutants and Urban Parameters on Atmospheric Dispersion and Temperature.

摘要

Two dimensional numerical simulations of planetary boundary layer flow indicate that urbanization (increase of surface roughness,changes in surface albedo,and the addition of anthropogenic heat sources) has a greater influence on the urban heat island than the addition of pollutants (gaseous and particulate) which are active in the radiative transfer processes of the heat budget. Although mid-day surface temperatures are decreased by adding such pollutants,temperatures at other times of day are increased. These simulations also indicate that heat islands are most pronounced with a snow cover on the ground. The warmer surface temperatures enhance low level pollutant dispersal with a consequent 25% concentration reduction. These results indicate that a change in land use is an important factor in local climate and weather modification.