HIRMOD: High-resolution atmospheric modelling in complex terrain for future climate simulations

The creation of climate-change scenarios at km-resolution in mountainous terrain is an unsolved problem although impact studies urgently need this. HIRMOD prepares for the time in the near future when computers will be powerful enough to accomplish this aim by dynamical downscaling with nonhydrostatic models. Two such models, MM5 and WRF, which have already produced realistic results at such high resolution in the Alps, will be improved for some key features (digital elevation and land-use data, initialisation, etc.). Then, systematic tests with episodic simulations will be carried out to determine the op-timum set-up in terms of horizontal and vertical resolution, domains, and physical parameterisations. Results will be compared with station data, remote sensing data, and coarse regional climate model output, and used in transport simulations to provide fur-ther validation with radon and other trace gases.