Ein diagnostisches Modell zur Berechnung von Trajektorien über dem Schweizer Mittelland
Abstract. The aim of the presented model (called WITRA) is to use the data of the automatic wind stations on the Swiss Plateau as a basis for calculating back-trajectories over a complex terrain. WITRA interpolates a three-dimensional windfield out of the measured data and the radio-sonde profile of Payerne. By a mathematical method developed by SASAKI (1958) based on the variational analysis and with regard to its application to the investigated problem by SHERMAN (1978), the windfield is slightly adjusted in a least-square sense in order to get it free of divergence, i. e. mass-consistent. Within the same step the complex terrain and its effects on the wind are taken into account. Trajectories can be calculated by a method mentioned by PETTERSSEN (1956) using a sequence of these windfields.