S. Suresh Babu
Space Physics Laboratory, Vikram Srabhai Space Centre
Thiruvananthapuram 695 022
Of all the atmospheric pollutants, aerosols are the most evident because they restrict visibility and whiten the otherwise deep blue of the sky, yet understanding of their influence in life on earth is very poor. They can play a critical role in many processes which impact on our lives either indirectly by altering the climate or directly by influencing the health of living beings. The atmospheric aerosol is the end product of a complex array of chemical and physical processes. Because of the complexity of these processes and the relatively short residence time, the chemical and physical characteristics of the aerosol exhibit a great deal of variability in time and space which makes its characterization as well as its impact assessment quite complex. One of the major objectives in the field of aerosol studies today is to understand the factors affecting the variability of aerosols and to characterize that variability.
Aerosols affect the Earth’s energy budget directly by scattering and absorbing radiation and indirectly by acting as cloud condensation nuclei and, thereby, affecting cloud properties. Moreover, the direct absorption of radiant energy by aerosols can influence the atmospheric temperature structure and thereby cloud formation, a phenomenon known as semi-direct effect. Aerosols can be transported both vertically as well as horizontally depending on the prevailing meteorological conditions. Elevated aerosol layers can be picked up by strong winds and transported from Africa or Asia to America and from America to Europe. Because aerosols vary widely from region to region, a multiple-measurement approach is necessary to assess their impacts on global climate. This session deals with the source apportionment techniques for the components of aerosol and it’s impacts including health effects, radiative forcing, aerosol- cloud interaction as well as the global and regional climate impacts.
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