Status and trends of dust storms in Iran from 1364 to 1384

Occurrence of the dust storm has been growing in recent years and has created many problems in some cities of Iran. In this paper, Climatology of dust storms in Iran is compiled based on observational data of 112 meteorological stations from 1985 to 2005. Results shows that total of days with dust storm are from 11 to 3833 Days. Weve divided the city into five groups. 1- Less than 492 days 2- from 588 to 1153 3- from 1243 to 1757 4- from 2007 to 2239 5- more than 3832 days. And then we reviewed each of them separately. The first group is fixed. Cities of this group are located mostly in North, East and Center of Country. The second group contains three parts: First, an ascending trend to 1992 and then a descending part to 1998 and again, an ascending part to 2005. Cities of second group are located south of country. The third group contains four parts: First, a downtrend to 1990 and then an ascending part to 1993 and again, a descending part to 1998 and finally, a branch of the ascending to 2005. Cities of the third group are located almost in the southwest. The cities of fourth group are located in the Sistan & Baloochestan province and are affected by the 120-Day wind. The occurrence of dust storm in the fourth group is ascending. Finally, using GIS and Interpolation systems, we have plotted dust storm zone Classification map of Iran from 1998 to 2005.