Synoptic characteristics of the spatial variability of spring dust storms over Saudi Arabia

Statistical and synoptic studies of spring dust storms over the Arabian Peninsula (AP) were performed using surface observations from 27 surface stations and meteorological data from the NCEP/NCAR reanalysis data set for the period from 1978 to 2008. The study showed that, spatially, the northern and eastern AP are the most affected by dust storms and that, temporally, the study period can be divided into two subperiods before and after 1995, with a pronounced increase before 1995 and a smooth increase (decrease) after 1995 with respect to dust (dust storms) types. The synoptic study reveals three main atmospheric systems: frontal systems over the northern region, Red Sea Trough (RST)-related systems over the western region and thermal low systems over the eastern region. Additionally, the synoptic study shows that all of the atmospheric systems are associated with a favorable pressure (geopotential) gradient area and that the shape and strength of the maximum wind and upper-layer atmospheric regimes are suitable for completely integrating the atmospheric layers. Moreover, the southern thermal low is a common synoptic component of dust-related atmospheric systems, but its effect is particularly pronounced on the atmospheric system of the eastern region.