The land-surface parameterization scheme BATS was incorporated into a diagnostic atmospheric modeling system, using an unstructured prismatic grid, to investigate the capability of a diagnostic tool, designed for emergency response, to assign the land-cover impact on the boundary layer structure and pollutant dispersion. In this framework, two applications were made over a complex alpine region with 14 different landuses. In the first application (case A), the effects of the snow and vegetation processes on the ground-atmosphere heat exchanges (such as snow melt, fractional ground shading, vegetation and snow-cover-dependent albedo, existence of transpiring plant surfaces, plant water budget including foliage and stem water storage, transpiration limitations by stomatal resistance and soil dryness) were taken into account, while in the second (case B), they were omitted. The results were compared with data from the TRANSALP experiment. Considerable differences were found between cases A and B concerning the sensible heat flux, the atmospheric stability and the mixing layer height while the pollutant concentration maxima were significantly underestimated in the second case. The localization of these effects by a diagnostic modeling system, with a minor increase in the computing time, is considered significantly important for the improvement of the accuracy and reliability of the results in case of emergency response.