Konferensartikel

Dust particles play an important role in air quality and environmental health. They affect both solar and terrestrial radiation by scattering and absorption and are therefore considered to be a significant climateforcing factor. Dust storms are natural hazards that affect daily life for an interval ranging from a few hours to a few days; and they are a very frequent phenomenon in Saudi Arabia; especially in the pre-monsoon season. On 10th March 2009 a widespread and severe dust storm event that lasted several hours struck Riyadh (24.9 1° N; 46.41° E; 764 m) and represented one of the most intense dust storms experienced in Saudi Arabia in the last two decades. In this study; the effect of this dust storm on meteorological parameters was investigated. These parameters are relative humidity; air temperature; visibility and atmospheric pressure. Around noon local time on the event day; with the arrival of the dust plume; there were dramatic changes in weather conditions. Air temperature dropped by about 6 oC; relative humidity increased dramatically reaching a value of 33 %. The visibility deteriorated dramatically to a value of 1 m. These results also; show that the effect of this storm was associated with an increase in both atmospheric pressure and relative humidity as well as a reduction in temperature and visibility for the two days following the storm in comparison with conditions before the storm. The impact of several other dust storms on meteorological parameters during the year of 2009 were investigated and compared to the March 10th storm. It was found that this storm had a greater effect on the meteorological variables than the other storms.

Dust Storm; Riyadh; Temperature; Solar Radiation