Simulating a windstorm upstream of steep mountains

Simulation of windstorms in the complex terrain in Iceland have revealed that the largest errors in simulated wind speed are often immediately upstream of steep mountains. Here, a windstorm in NW-Iceland is simulated with the MM5 model with a horizontal resolution up to 330 meters. The greater the resolution is, the steeper is the mountain and the more correct is the simulated wind speed immediately upstream of the mountain. The simulations confirm that the steepness of the mountains, and not only their height, is of great importance for the deceleration of the upstream flow.