This document contains the presentation by Ranjit Kumar on Aerosol chemistry and climate change and public health at an Indo Gangetic Plain in India, presented at National climate research conference, IIT Delhi, March 5-6, 2010. Major irritants of the environment are global warming, climate change, ozone depletion, acid rain, visibility impairment etc. Climate change has been experienced in the form of unpredictable rain, very low temperature in the winter and extremely high temperature in the summer, heat related mortality and pollution related mortality and morbidity. Aerosol and its constituents play an important role in climate change, and deposition of atmospheric components to the earth surfaces. Knowledge of chemistry of aerosols is required for the assessment of its role in the climate change, total deposition of acidity at the earth