Mary Barth specializes in the effects of clouds on the chemistry of the atmosphere. Her research, which uses both computer simulations and observations of the atmosphere, focuses on such questions as how clouds and lightning influence airborne chemicals, including water vapor and ozone. Such work can advance our understanding of climate change as well as the atmospheric processes that shield Earth from incoming ultraviolet radiation. Barth is a principal investigator on a field campaign, known as DC3, that will use aircraft and ground-based instruments to better understand the influence of storms on atmospheric chemistry. She divides her time between two NCAR divisions: Mesoscale and Microscale Meteorology and Atmospheric Chemistry.