My students and I work collaboratively with colleagues in the UOW Centre for Atmospheric Chemistry, as well as researchers around the world, to investigate a variety of issues related to atmospheric composition, chemistry, and climate.
Southern Hemisphere Atmospheric Composition
Short-lived gases in the atmosphere play a critical role in regulating atmospheric composition, air quality, and climate forcing, with implications for issues ranging from human health to climate change. In the southern hemisphere, the relative importance different sources in controlling the abundance of these gases is poorly understood. Biogenic emissions in particular play a major role in many southern hemisphere environments, and longe-range transport can introduce pollution to otherwise clean environments. Using a global chemical transport model constrained by ground-based and satellite data, we are providing new constraints on this problem.
Mercury is a neurotoxin that is emitted by anthropogenic activity and bioaccumulates in marine and terrestrial foodwebs. The biogeochemical cycling of mercury between the atmosphere, ocean, and snow/ice in the Southern Hemisphere is still extremely uncertain. We are using observations of mercury in the Antarctic and southern ocean to constrain a biogeochemical model of mercury and evaluate the impacts for polar mercury cycling. We are also investigating the drivers of mercury variability across the Southern Hemisphere and the links to mercury exposure.
Biogenic Emissions and Chemistry
Both the Southeast United States and Southeast Austraia are global hotspot of biogenic emissions from vegetation in summer. Parts of these region also contain large anthropogenic pollution sources while other parts are largely pristine, providing significant heterogeneity in chemical environments. Understanding the chemistry that results from biogenic emissions was one of several goals of the NASA SEAC4RS (Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys) aircraft campaign, which took place in August-September 2013, and is a goal of the planned COALA (Characterizing Organics and Aerosol Loading over Australia) atmospheric chemistry field experiment. We are using data from SEAC4RS to reduce model uncertainty in biogenic emissions and chemistry, and are contributing to the planning and development of the COALA campaign.