The study of physico-chemical properties of atmospheric aerosol is important as these influence the Earth's climate directly by scattering and absorbing solar radiation, and indirectly by acting as cloud condensation nuclei. Nowadays, the physico-chemical properties of aerosols are being measured using space as well as ground-based sensors. Although tremendous progress has been made to improve observation systems, yet till date our understanding of physico-chemical properties of aerosol is limited. A review of available literature indicates that the surface cooling effect of aerosol is strengthened with the increase in absorbing aerosol particles in the atmosphere in response to warming. This effect might change the microphysical properties of the clouds and in due time climate. The current state of knowledge about aerosol processes where it affects climate during interaction with clouds is limited. Because aerosol processes are too complex and couldn't represent accurately in global climate models, so it is crucial in terms of predicting climate. It is therefore pertinent that future research needs to focus on a detailed understanding of physico-chemical properties of aerosols and underlying aerosol processes particularly aerosol-cloud interactions and their effect on climate.