Atmospheric aerosols and their role in climate change

As in the case for increased emissions of greenhouse gases; increased emissions of atmospheric aerosols from human activity perturb the climate of the Earth. Aerosols exert a significant radiative forcing of climate via aerosol–radiation and aerosol–cloud interactions; these processes will be explained in relatively simple terms by concentrating on the underlying physical processes. We shall see that while the net impact of anthropogenic aerosol emissions is to cool the planet, significant uncertainty arises from the complexity of aerosol absorption, and the impacts of aerosols on cloud microphysics. Aerosols are also implicated in climate feedback mechanisms where atmospheric concentrations of natural aerosols such as sea salt, mineral dust, and organic aerosols are potentially perturbed in response to future climate change scenarios. We also briefly investigate the contentious issue of aerosols in potential climate engineering via solar radiation management schemes.