Haboob dust storms of the southern Arabian Peninsula

The Arabic word haboob,'' meaning strong wind,'' describes a weather phenomenon characterized by immense walls of blowing sand and dust. Common to many parts of the Middle East, northern Africa, and the southwestern United States, haboobs are spawned by strong mesoscale downdrafts, making their prediction by coarse-grid numerical models difficult in comparison to dust forced by synoptic-scale dynamics. The United Arab Emirates Unified Aerosol Experiment (UAE(2)), an extensive field program conducted over the southeastern Arabian Peninsula during the summer of 2004, provided a unique opportunity to observe the haboob activity common to this region by way of a large assortment of satellite, radar, lidar, and meteorological station network observations. Here, we present results based on the UAE(2) data set which add insight to the formation processes, multiscale structure, and transient behavior of haboobs as well as their potential importance to the regional aerosol burden. Satellite imagery and surface radar data assisted in the interpretation of highly dynamic storm evolution and outflow interactions. An idealized model of haboob dust production, parameterized by the strength and duration of the downburst, suggested that haboobs could be responsible for a nonnegligible component of the regional-scale total dust production (up to 30% over a 1000 x 1000 km domain).