A DEEP STUDY ON THE OPTICAL PROPERTIES OF AEROSOLS

ABSTRACT

Aerosols in the atmosphere can either directly affect the radiative balance of the Earth by scattering and absorbing solar energy, or indirectly by altering cloud features. Studies of the influence of aerosols on the climate need knowledge of aerosol optical characteristics. Despite the abundance of research into the topic, there are still significant gaps in our understanding of the optical features of aerosols, particularly their absorption qualities. Direct, indirect (albedo effect and cloud lifespan impact), and semi-direct effects of aerosols on radiation are all characterized as either positive or negative disturbances to the radiation balance. Anthropogenic aerosols have a negative direct effect overall (cooling), however some components may have a beneficial effect (warming). By increasing cloud optical depth and cloud cover, respectively, the albedo effect and the cloud lifespan effect cool the atmosphere. Carbonaceous aerosols and dust are two examples of absorbing aerosols that can directly warm the atmosphere by exerting a positive forcing towards the top of the sky and a negative forcing near the surface. The warming impact of black carbon aerosols created by internal mixing is greater than that of black carbon particles created by external mixing. Aerosol absorption has a semidirect effect, which may increase this warming. This study covers numerous significant concerns to be addressed in future studies, as well as evaluates the present state of research on the optical characteristics and radiative impacts of aerosols based on observational (ground- and satellite-based) and simulation studies.

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