Authors: I Schicker P Seibert
Publish Date: 2009/02/05
Volume: 103, Issue: 1-4, Pages: 211-222
Abstract
A stateoftheart numerical nonhydrostatic model is applied to simulate meteorological conditions during a winter smog episode in a large Alpine valley This case study illustrates what such models are capable of and where there are limitations The PSU/NCAR mesoscale model known as MM5 version 37 is used to simulate the period 31 January 2004 until 9 February 2004 when elevated pollution levels were observed in the Inn Valley The MM5 model was used with the modifications provided by G Zängl and with two different boundary layer schemes Simulation results of five different model runs are compared with wind and temperature observations in the valley at mountain stations and outside the Alps A comparison of the results of the runs using a resolution of 24 km in the innermost nest with a run with 08 km resolution shows that 24 km is insufficient for acceptable results while with 08 km the characteristic features could be reproduced This concerns mainly the temperature and stability inside the Inn Valley whereas conditions in the Alpine foreland are simulated reasonably even at the coarser resolution
Keywords: