Windfelduntersuchung in Zürich : Ergebnisse von Messungen und numerischen Modellierungen

Abstract. From 1985 to 1989 the Department of Geography of the ETH in Zürich carried out a project called "Stadtklima Zürich". Following a brief description of the project the paper is centered on theoretical and experimental studies concerning the air-flow above Zürich.
The wind measurements were undertaken with a network of about 20 stations. The interpretation of these measurements was concentrated on important weather types. Apart from a cartographie representation of the measured data, a diagnostic model (DIAMO) was used for the data interpolation. A non-hydrostatic numerical model (MONARC) helped to interprete dynamicalm processes over complex topography.
With an example of a Situation with easterly synoptic wind the measured windfield is compared with the simulations which show a fairly good correspondence. Measurements over the railroad tracks near the Central Station show the transition from mesoscale topographic to microscale or urban building effects. By using a particle trajectory model (LADI and TRAMO), the problem of air pollution dispersion over the complex urban topography is discussed.