For much of my career my research has focused on the chemistry of Atmospheric Energy-Related pollutants (AER pollutants). The principal substances of concern have been sulfur and nitrogen oxides emitted into the troposphere as byproducts of fossil fuel combustion, and their oxidation products, i.e., sulfuric acid and nitric acid and the salts of these species. These substances are of concern from the perspective of human health, acid deposition, visibility reduction, and climate change. More recently my research interest has turned increasingly to understanding the response of Earth’s climate system to the increase of carbon dioxide (CO2) and other so-called forcing agents, substances which change the radiation budget of the planet, specifically including also the influences of atmospheric aerosols (submicroscopic particles suspended in air).