نوع مقاله : مقاله پژوهشی
عنوان مقاله English
نویسندگان English
The focus of this study is on the concentration trends of PM2.5 and PM10 pollutants in Qom City and their connection to sand and dust storms. Shokohiyeh, Markaz Tahghighat, and Nirogah e Hararati stations data, including wind direction and speed, and present codes related to sand and dust storms were used for our analysis In addition, we used the Mann-Kendall trend test to examine the PM2.5 and PM10 concentrations at four air pollution-monitoring stations in Qom City including Modiriat e Bohran, Emam, Pol-e Hojjatieh, and Pardisan in Qom City during the available statistical period (2017-2024). The daily time series results for PM2.5 and PM10 pollutants show that the concentration of both pollutants is above the USEPA standard at all stations for a significant portion of the year.The highest concentration of PM2.5 was recorded at Emam and Modiriat-e-Bohran stations, reaching up to 500 µg/m³. The highest concentration of PM10 was recorded at Modiriat-e-Bohran station (up to 770 µg/m³), which is the closest pollution monitoring station to the internal dust sources of Qom Province, as well as the Pol-e-Hojjatieh station. Analyzing the time series of pollutants during holidays and non-holidays reveals a decrease in the concentration of both pollutants in holidays, particularly PM2.5. Both PM2.5 and PM10 pollutants showed an increasing trend at the Pardisan station during the spring season, as indicated by the Mann-Kendall test results. This behavior could be attributed to the blowing of westerly winds, leading to dust intrusion from the central sand and dust source in the province into this area, while this area's concentration of urban pollutants could also be caused by its proximity to Nirogah e Hararati. An examination of the number of polluted days with reported sand and dust storms shows that PM10 was recorded 75% of the time, while PM2.5 was recorded 31% of the studied period. The highest number of polluted days occurred in summer, followed by spring. By taking the easterly wind direction in summer and the westerly wind direction during the other three seasons in Qom City into consideration, it can be concluded that the pollution in Qom during summer is primarily caused by sand and dust emitted from the southeastern dust source.
کلیدواژهها English