The Environmental Chemical Sciences Program in the Chemistry Division at the National Science Foundation supports Professor Cort Anastasio of the University of California- Davis to study how photochemical reactions in snow can significantly affect the chemistry and composition of snow and the overlying atmosphere. We know relatively little about the rates or mechanisms of these processes, and further complicating matters, it appears that the photochemistry of a given solute depends on where the solute is located in/on ice. The two main goals of this proposal are to: (1) quantify how the photoreaction rates of environmentally relevant solutes vary with location in/on ice and (2) determine whether a freezing point depression model can predict solute reactivity. These goals will be achieved using laboratory experiments with carefully characterized ice samples and illumination conditions. This work has the potential to transform our understanding of molecular reactions in/on ice by revealing how chemistry varies with ice compartment and by providing an experimentally-confirmed kinetic framework that could be used to model snow chemistry. The broader impacts of this work include: (1) training and mentoring a postdoctoral fellow, a graduate student, and several undergraduate students, (2) integrating research results into undergraduate and graduate courses, and (3) developing a seminar series on climate change to be offered in Sacramento to engage state, county, and city policy makers as well as the public.
