Abstract
Winter dust cases over the northern Arabian Peninsula were selected using a threshold aerosol index from the Total Ozone Mapping Spectrometer (TOMS)
instrument
. The results reveal that most of the winters were dusty, and a few dust cases were widespread.
A statistical analysis was conducted using the empirical orthogonal function (EOF) for the sea-level pressure (SLP) during the identified widespread dust cases; four principle modes (patterns) covered approximately 63 % of the dust cases. Furthermore, the patterns were synoptically analyzed using the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) Reanalysis datasets. The synoptic features of the patterns demonstrated that, although the strength of the dust in the Arabian Peninsula was controlled by the troughs from the Sudan and India low-pressure systems, the frequency of the dust was controlled by the Azores and Siberian high-pressure systems. Frequent dust cases occurred when the Azores high pressure was pronounced over the western region or the Siberian high pressure dominated over the eastern region. Additionally, this study indicates that the pattern frequencies increased when the high-pressure systems were stronger than the low-pressure systems but decreased when the two inverse systems had comparable strengths.