The analysis of dust storm hazard occurrence and its variations trend in west & southwest of Iran

Iran is a disaster prone country. Among the 40 different types of natural disasters، about 31 types have been identified in Iran. One of the most important consequences of climate change is to increase dust storm disaster occurrence in recent years that affect different sections of the society directly or indirectly. The sever impacts of the dust storm hazard are such as the increase in respiratory diseases، disorder in ground and air transportation، environmental destruction، pollution of agricultural products، and high density in health centers due to its side effects. Thus، this research aims to study the time distribution of dust storm occurrence as monthly، seasonal and annual and to determine variations and managing strategies in order to deal with this phenomenon based on the appropriate situations. In this applied and statistical-descriptive study، west and southwest of Iran were studied. Therefore، the monthly and annual data of dusty days were prepared and extracted from 11 meteorological synoptic stations from the meteorological organization by using Excel، descriptive statistical indices and Mann-Kendall method. The most critical condition of dust storm occurs in the southwest of Iran. The hottest months of the year، (July and August) are the most severe times of occurring this phenomenon. Dusty days started in six months (from April to September); and the frequent occurrence is in spring and summer in west and southwest regions respectively. Due to geographical situation and region structure، dusty days’ occurrence is not the same and increases from the north to south. The significant increase and decrease is not observed in dust storm phenomenon annual and monthly. There is only a significant increase in Ahvaz station (95%). This phenomenon involved west and southwest regions with different intensity from mid-spring to mid-autumn. The gradual increasing of this phenomenon got started from April to July. Evaluating the time of occurrence is annual and monthly. Lack of the significant increasing and decreasing trend in occurring long-term changes makes it a top priority for organizations to deal with natural disasters in order to have disaster management programs. Understanding this phenomenon and time distribution plays an effective role in decreasing of damaging impacts of this phenomenon before and during crisis in order to implement prevention programs and management programs especially in the field of health in critical areas in accordance with the geographical conditions.