[Climate and air pollution]

Climate and air pollution are closely related. On the one hand, the climate is more and more influenced, locally as well as globally, by the tremendous concentration of pollutants in our atmosphere. Certain elements of the climate are, on the other hand, directly responsible for the process of dilution and dispersion of pollution emission. Of particular importance is the phenomen of ventilation and inversion. The significance of knowing the regional climatic peculiarities is presented by ways of a smallspace-example of the ventilation existing at the valley of river Aare and of the frequency of inversion existing at the Aare-trench situated north of Berne. Such knowledge should increasingly be used to influence regional planning, to assist in the determination of the position of any important source of pollution and should help to determine the selection of suitable living and recreation areas. Unfavorable meteorological-climatological conditions could aggravate a situation whereby harmless concentrations of pollutants could lead locally to critical proportions. For the better understanding of the meteorological and climatological processes within the lowest 500 m-level of our atmosphere, an increased effort of research should be considered in this connection. Through the use of improved data processing in connection with more closely meshed measuring networks, and of automatic recording facilities, as well as through the increased use of physical models, the problem of immission in our heavily valleyed country could be investigated more thoroughly.