Zoning Map of Dust Phenomenon in Markazi Province

Markazi Province is located in an arid and semi-arid area and is regarded as one of the desert provinces in Iran. In this province, more than 490000 hectares of pasturelands and wetlands have changed into desert lands which are at the center of the release of local dust. On the other hand, the dust from ouside the west and the central desert of Iran and from Qom province at the east have affected Markazi Province. Nowadays, suspended particles are the main pollutants of Markazi Province and Arak city, which are one of the main factors involved in air pollution in Markazi Province. The present study aims to make a spatial analysis of dust phenomenon in Markazi Province within 2007-2014. In the present study, the daily statistics for dust with a code (06) and horizontal visibility were received from 10 synoptic stations of Meteorological Department of Markazi Province and were estimated daily, monthly and annually. Then, the zoning map of dust phenomenon for the entire period and the year 2014 was drawn using the GIS software. The results indicated that Arak and Saveh cities have a maximum amount of dust at this interval and the extent of dust decreases by proceeding towards Tafresh and Khondab stations. Arak Meteorological Station with 1322 days and Tafresh Station with 85 days have had the maximum and minimum extent of dust, respectively. The percentage of the zoning area affected by dust in Markazi Provinc showed that about 65% and 35% of dust in Markazi Province are local and from outside, respectively.