The Effect of Dust Aerosols on Some Meteorological Parameters in Two Dry and Humid Areas

The current study compares the effect of dust aerosols on two meteorological variables, temperature and relative humidity, in two different regions. For this purpose, AOD data from the Moderate Resolution Imaging Spectroradiometer (MODIS) were used for Kermanshah and Ahvaz from 2010 to 2015. In a subjective review, a day with the highest AOD value was highlighted. The effects of dust on temperature and relative humidity variations were investigated on the selected day and compared with a clean day. The effect of aerosols on the vertical profile of temperature shows that increasing aerosol concentrations in Kermanshah causes a rise in temperature at lower atmosphere during the day due to the absorption of solar radiation by dust aerosols and a decrease in temperature at night due to the longwave radiative cooling. Because of the high seasonal humidity in Ahvaz, the nature of the aerosols has resulted in the greenhouse effect, which has raised the temperature by absorbing radiation at night. The effect of aerosols on the vertical profile of relative humidity differs between Kermanshah and Ahvaz. The relative humidity has risen, particularly at lower levels in Ahvaz during the dusty days and nights. The increase in aerosols in both Ahvaz and Kermanshah regions had no effect on precipitation based on data from the Iran Meteorological Organization. The reason could be lack of precipitating systems in the two regions during the warm seasons.