Abstract

Secondary Inorganic Aerosols (SIA) is of core relevance in climate, public health and ecosystem. Aerosols can be categorized as primary, when it is directly released from sources, and termed secondary, when subsequently formed in the atmosphere from chemical processes involving a set of precursor gases. SIA usually consist of a mixture of components: Sulfates, nitrates, ammonium, black carbon, sea salt, mineral dust etc. They affect the climate explicitly by scattering and absorbing of solar radiation and implicitly by modifying the clouds properties. The principal parameters that governed the environmental and health effects of aerosols particles are their size, concentration, chemical composition, and structure. These parameters, however, are temporally and spatially highly variable. Multicity studies had shown that associations between SIA and morbidity and mortality differ across locations, with this discrepancy attributed in part to diversity in size effect and chemical composition. The review concludes that SIA due to their size and chemical composition has a great impact on the climate system and human health. Also,the short lifetime of SIA (days/weeks) implies that their effects are more regional and less persistent into the future than those of the long lived greenhouse gases (GHG). In devising policies to curb health effects, simultaneously, climate impacts should be considered, and vice versa. Thus it is becoming more and more lucid that regional air quality and global climate issues are intricately linked to one another.

Keywords

secondary inorganic aerosols, atmospheric chemistry, climate system, health effects, greenhouse gases, air quality