Extended Abstract
Introduction: According to their specific geographic and climatic conditions, the extent and intensity of dust storms in the west and southwest parts of Iran have made this phenomenon one of the principal environmental hazards in these regions. The extent of dust storms, their significant effects on health, economy, environment, and agriculture, and their increasing trend have drawn the attention of many researchers. The recent study is composed of data analysis of dust storms by Iran Meteorological Organization Earth Database, synoptic analysis of weather and climate patterns causing and transmitting dust using middle and upper atmosphere data in Sanandaj, Kermanshah, and Ilam stations and tracking wind packages carrying dust particles using HYSPLIT model with forward and backward methods.
Materials and Methods: To analyze atomosphoric patterns, the middle and upper atmosphere data such as the sea level pressure data, level of 500 hPa geo-potential height from NCEP/NCAR databasewere drawn using GRADS software. HYSPLIT model and MODIS images for dust storms.were used to recognize the origin of dust storms and wind flow routing in the stations.
Results and Discussion: Earth database investigations show that the year 2008 has one of the most extreme dust storms in terms of visibility reduction and durability of days with dust storm in the study period. From 2 to 5 April 2008 the most extreme dust storms with visibility of fewer than 500 meter occured in the stations. The results of wind flow routing by the HYSPLIT model showed that the origin of the dust storm mass was North West of Iraq and east of Syria, which had entered Iran with a north west-south east direction. The middle and upper atmospheric circulation base results show that west winds occurred with a low-pressure center in the East of Iran and high pressure in the North of Africa, causing the entrance of dust to this region. As one of the most intense dust storms of recent years, the mentioned dust storm can help by recognizing atmosphere patterns causing this phenomenon and routing winds transmitting aerosols.
Conclusion: According to the results of this study which has examined the relationship between large scale synoptic patterns and a variety of space-time dust storm activities in Iran using synoptic maps of sea level pressure circulation patterns, 500 hPa geo-potential height of dust storms in the studied stations, and wind flow routing model, it can be concluded that dynamic models can be presented by consensus of various specialists for this destructive environmental phenomenon-although using satellite imagery and dust storm capability and investigating them can be of great importance for future studies. In general, the results of this research show that wind flow routing model and atmosphere studies have the suitable capability for recognizing and monitoring dust storm paths.