Atmospheric aerosols along with green house gases are the principal internal agents of climate change. However, the regional and global impact of atmospheric aerosols on climate is still uncertain owing to the large heterogeneity in their spatial and temporal distribution throughout the globe. Variability of sources or origin of different aerosols as well as their short residence times result in heterogeneity of aerosol characteristics on both regional and global domain. In the context of regional characterization of aerosols over South-East Asia, the north-eastern part of India is unique owing to its characteristic dense vegetation, vast water bodies, heavy rainfall pattern and the unique topography with mountains in the north, east and south and densely populated Indo Gangetic plains towards the west. In this PhD dissertation the optical and microphysical properties of aerosols have been studied and their impact on climate through radiative forcing is assessed over a remote continental location Dibrugarh, in north-east India. The aerosol environment of Dibrugarh is found to be heavily influenced by long range transportation together with local generation.