Our research focuses on gas and particle-phase pollutants in the atmosphere – how they form and how they transform due to chemical and physical processes. Atmospheric particles are important for many reasons, including their adverse effects on human health, on regional visibility and their uncertain effect on climate. Our research tools include laboratory experiments using a state-of-the-art environmental chamber facility, ambient measurements, and mathematical modeling. A main goal of our research is to make better-informed recommendations for environmental policies aimed at improving air quality and human health.