Studies of Urban Climates and Air Pollution in Switzerland

Abstract

In addition to an assessment of the factors that are responsible for urban climate change, this paper describes climatological studies and peculiarities of some Swiss cities. Although these cities are small, urban air pollution presents a real problem for urban planning. This is a result of the narrow street canyons, the high traffic concentration and the complex topography, which favors air stagnation during anticyclonic weather conditions. In recent studies of urban climate and air pollution, scientists have tried to find a balance not only between modeling and observational studies, but also between specialized investigations and integrating studies which lead to an application in land-use planning and politics. In almost every city, research efforts have concentrated on the dynamics of temperature stratification and airflow. Because of the smaller size of Swiss urban areas and the existence of a complex topography, the interactions between three effects important for transport and dispersion of air pollutants must be studied. These interactions involve heat islands and city-induced airflows, the influence of synoptic winds on boundary layer airflows and the significance of local airflows in complex terrain.