Atmospheric Dust Seasonal Variability from Riyadh

Atmospheric mineral dust aerosols play an important role in the local and regional climate systems. They also have a great deal of disturbance to human life by reducing air quality and visibility. Riyadh the capital of Saudi Arabia is located at the middle if the Arabian peninsula one of the major contributors to the global aerosol budget. Several dust storms that occurred during the period from 1/1/1995-31/5/2013 are analyzed in terms of their type, origin, frequency and intensity. King Khalid airport weather station data, global aerosol index and NOAA OSEI images were analyzed. 12 categories in the synop code are used to identify dust occurrences and their seasonal variation. in general codes 6 and 7 " Widespread dust in suspension not raised by wind", " Dust or sand raised by wind", respectively are more dominant. winter-spring transition period is where frequency peaks, another peak in on spring-summer transition. two sources are identified Iraqi desserts and African Sahara, with the former being the main contributor, especially in the winter-spring peak. local surface heating seems to play an important role in storm trajectories, and durations.