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Showing 2 results for Hysplit

. P Broomandi, A Bakhtiar Pour,
Volume 9, Issue 4 (3-2017)
Abstract

Background and Objective: The aim of this study was to investigate the physico-chemical properties, size distribution and shape of the falling mineral dusts over Masjed Soleyman and to identify their origins. Also, seasonal and annual variations of climatic parameters and their relation with dust storm occurrence were investigated.

Materials and Methods: The collected samples were as result of dry deposition process during warm season in 2013. Particle size distribution was determined by laser size diffraction. Chemical and mineralogical compositions were measured with atomic absorption spectrophotometer (AAS) and X-ray diffraction (XRD). Crustal and non-crustal origins for elements in the dust samples were determined using enrichment factor (EF). In addition, dust storm sources were identified using the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT.4).

Results: The study of the annual and seasonal changes in meteorological parameters associated with the occurrence of dust storms indicated an agreement between the occurrence of dusty days, temperature and rainfall in summer. The chemical and mineralogical analysis of dust particles demonstrated that the likely origin of these particles is of neighboring countries in the South West of Iran. Also, some of the detected trace elements had non-crustal sources.

Conclusion: Using HYSPLIT.4 results, it was concluded that the main origin of dust storms are North West of Iraq and East of Syria in Masjed Soleyman.


Fatemeh Bagheri, Mehri Rezayi,
Volume 14, Issue 1 (5-2021)
Abstract

Background and Objective: The aim of this study was to investigate dust origin particulate (PM2.5) in Mashhad city in a long period of time (2014-2019) based on unhealthy days. Furthermore, changes in meteorological parameters and their relationship with dust storms have also been investigated.
Materials and Methods: In order to locate dust pollution hotspots in mashhad air, first, information about unhealthy days of Mashhad city in a 5-year period was obtained from the site of Mashhad Pollutants Monitoring Center and then HYSPLIT model was used to locate air pollution hotspots caused by particulate matter. To verify the results, the outputs obtained from this model were also compared with the DREAM8b model.
Results: By examining the meteorological parameters and its relationship with the outputs obtained from THEHYSPLIT and DREAM8b models, the maximum wind speed and relative humidity were obtained in autumn. There was no rainfall in the studied days (19 days) and the highest temperature was related to summer, indicating the relationship between the occurrences of polluted days due to particulate matter less than μ 2.5, wind speed and relative humidity in autumn. The results of the two models showed that the southern and northeastern regions of Mashhad city had the highest source of dust particles during the studied days.
Conclusion:  Although in previous articles, the origin of dust in Mashhad city was announced outside the geographical boundaries of the province, long-term investigation at low altitude (below 10m) showed that local origin of dust have an essential role in air pollution in Mashhad city under unstable atmospheric conditions. Inappropriate use of agricultural lands and severe changes in land use often in the northern region and implementation of construction projects such as the southern belt of Mashhad city play essential roles in increasing PM2.5 particles in the air of Mashhad. This finding shows the importance of decision making for the implementation of soil stabilization projects etc... at the local level.


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