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The present study deals with the aerosol optical properties which are assessed during the period 2007 to 2009 over Mohal (31.9A(0)N, 77.12A(0)E) in the northwestern Indian Himalaya, using ground-based measurements and multi-satellite data. The daily average value of aerosol optical depth (AOD) at 500 nm, ngstrom exponent and turbidity coefficient are 0.24 +/- A 0.08, 1.02 +/- A 0.34 and 0.13 +/- A 0.05, respectively. The comparative study of satellite and ground-based measurements reveals that the percentage retrieval for daily AOD at 550 nm over Mohal within the expected accuracy (Delta tau (p lambda) = +/- 0.05 +/- A 0.15 tau (p lambda) ) is around 87%, with a significant correlation coefficient of 0.76. The present study suggests that the retrieval of AOD through satellite data is able to characterise the distribution of AOD over Mohal. However, further efforts are needed in order to eliminate systematic errors in the existing Moderate Resolution Imaging Spectroradiometer (MODIS) algorithm. The transport of desert dust and anthropogenic aerosol during high aerosol loading days caused a significant reduction in surface-reaching solar radiation by 149 and 117%, respectively. This large reduction in surface-reaching solar radiation increased the atmospheric heating rate by 0.93 and 0.72 K day(-1), respectively. This study indicates significant climatic implications due to the transport of aerosols in the northwestern Indian Himalaya.