New Particle Formation in Marine, Urban, and Terrestrial Environments—A Tribute to Robert A. Duce

Fine particulate matter (PM) or aerosols represent a major environmental problem, causing degradation in visibility, directly and indirectly impacting climate, and posing negative human health effects. A majority of atmospheric fine PM is produced through new particle formation in various environments. Aerosol nucleation events have been frequently observed in urban, forested, and marine areas, where extremely high concentrations (>104 particle cm-3) of nucleation mode nanoparticles are generated. New particle formation occurs in two distinct stages (Figure 1), i.e., nucleation of a critical cluster (or nucleus) and subsequent growth of the critical nucleus to a detectable size of 1.5 to 3 nm. This presentation will discuss our results on experimental and field studies of formation of atmospheric nanoparticles in diverse environments and contributions of Robert A. Duce to the development of the Atmospheric Chemistry Program at Texas A&M University.