Гидрология: текущие исследования

Long-Term Variations of Aerosols Concentration over Ten Populated Cities in Iran based on Satellite Data

Abstract

Foroozan Arkian

In this study, three different sensors of satellites including the Moderate Resolution Imaging Spectroradiometer (MODIS), Multi-angle Imaging Spectroradiometer (MISR), and Total Ozone Mapping Spectrometer (TOMS) were used to study spatial and temporal variations of aerosols over ten populated cities in Iran. Also, the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model was used for analyzing the origins of air masses and their trajectory in the area. An increasing trend in Aerosol concentration was observed in the most studied cities in Iran during 1979-2016. The cities in western part of Iran had the highest annual mean of aerosol concentration. The highest AOD value (0.76 ± 0.51) was recorded in May 2012 over Ahvaz, and lowest value (0.035 ± 0.27) was recorded in December 2013 over Tabriz. After Ahvaz, the highest AOD value was found over Tehran (annual mean: 0.11 ± 0.20). The results show that AOD increases with increasing industrial activities, but the increased frequency of aerosols due to land degradation and desertification is more powerful in Iran. The trajectories analysis by the HYSPLIT model showed that the air masses come from Egypt, Syria, and Lebanon, and passed over the Iraq and then reached to Iran during summer. Aerosol Radiative Forcing (ARF) has been analyzed for Zanjan (AERONET site) during 2010-2013. The ARF at surface and top of the atmosphere were found to be ranging from -79 wm-2 to -10 Wm-2 (average: -33.45 Wm-2) and -25 wm-2 to 6 wm-2 (average: -12.80 Wm-2), respectively.