Human activities (such as the intensive use of fossil fuel, urbanization, deforestation, agricultural expansion or intensification) have been imposing significant perturbations to the atmosphere. We are interested in a wide range of research topics related to global environmental change, especially the interactions among emissions, climate, atmospheric chemistry, air quality, land use/land cover and biosphere-atmosphere exchange. Our research activities have covered:
(1) The impacts of global change on atmospheric chemistry and air quality through various stressors (e.g., Wu et al., 2008ab, 2012; Hickman et al. 2014; Zhang et al., 2014a);
(2) Long-range transport of atmospheric pollutants and the impacts on atmospheric environment (e.g., Huang et al., 2013; Kumar et al., 2013; Zhang et al., 2014b);
(3) Impacts of invasive species on the environment and ecosystems (e.g., Hickman et al., 2010);
(4) Impacts of extreme events (such as heat waves, lightning, wildfires, etc.) on the environment (in particular air quality) in the context of global change (e.g., Huang et al., 2014);
(5) The cycling and circulation of heavy metal pollutants (such as mercury and arsenic) in the global environment and the ecosystems as well as their implications for public policy and environmental sustainability (e.g., Wai et al., 2014).
Our research has been funded by multiple sponsors including the U.S. EPA, NSF, NIH, NASA, and ORAU.
Current research projects:
v Impacts of climate change on extreme air pollution meteorology and air quality
Climate change can significantly affect air pollution meteorology. Of particular concern is the changes in extreme meteorological events (such as heat waves, temperature inversion, atmospheric stagnation, lightning and wildfires) that have important implications for air quality and public health. We have been analyzing the long-term observational datasets for meteorology around the world to examine the likely trends for extreme air pollution meteorology in the context of global climate change. Global models are combined with statistical analysis to interpret these identified trends and examine their implications for air quality in the context of global change. The following plot shows the correlation between high pollution episodes in the United States and various extreme meteorological events:
v Cycling and circulation of toxic heavy metals in the global environment
The emissions, atmospheric transport and deposition of heavy metal pollutants such as mercury and arsenic have impotent implications for public health and the ecosystems. We aim to improve our understanding of the cycling and circulation of these pollutants in the global environment and the source-receptor relationships for various regions as well as the perturbations from various stressors in the context of global change. The following plot shows the model simulated arsenic concentration in ambient air compared to measurements (in ng/m3):
For more details on the results from our research projects, please check out our publications.