Validation of a numerical wind forecast by dust image

A satellite image of a major sandstorm is used to assess the quality of a high-resolution forecast of the wind field in South-Iceland. The image shows transport of sand that indicates corner winds of different magnitudes, orographic wakes with weak winds and vortices and downslope acceleration of the winds. The wind simulation and the observations confirm the importance of local enhancement of the wind during erosion events. Trajectory analysis indicate that descending motion downstream of Greenland led to a low-level inversion that contributed to the local variability in the wind speed over Iceland.