Observations and cloud-resolving modeling of haboob dust storms over the Arabian Peninsula

Although the amount of rainfall in the model was slightly underestimated compared to the satellite measurements, it was approximately double the rainfall in the reanalysis. The convection-associated dust outbreaks were simulated well, with the aerosols optical depth magnitude and the temporal variability being in good agreement with both the ground-based and satellite aerosol retrievals. The model captured the major dust generation patterns, transport pathways, and several of the largest haboobs identified from the satellite observations.

About 25 Tg of dust was emitted in the Arabian Peninsula during the 10-day period. Approximately 40% of the locally deposited dust was subject to wet removal processes. During periods of high local dust production, the WRF-Chem model underestimated the PM10 mass concentration (associated mostly with dust particles larger than 3 mu m in diameter) by nearly a factor of 2.

This suggests that the current dust parameterizations, which prescribe the size distribution of the emitted dust, underestimate the number of large particles that increases at strong wind conditions.