Simulation of strong wind events in the Antarctic

Reanalysis/analysis fields are used to examine the synoptic background in which strong wind events (SWEs) in the Antarctic take place. SWEs are a feature of the extended winter season and involve a complex interaction between the downslope buoyancy forcing and the pressure gradient force from synoptic-scale cyclones, resulting in a deepening of pressure off the coast and an increase of pressure inland. Orientation of the valleys in relation to the cyclone track is critical in enabling enhancement of the katabatic winds. Comparison with high-resolution numerical simulations showed that the reanalysis/analysis fields are able to capture the large-scale synoptic features and the associated enhancement of the katabatic flow but underestimated the observed wind speed if it was strongly influenced by local topographical conditions. Model simulations showed some improvement through increasing model resolution and physics optimization.