Research on Aerosol-Climate Interactions
Our group's research interests broadly focus on studying the impacts of aerosols (which are tiny particles in the atmosphere) on the Earth system. Because of the many ways these aerosols can interact with several aspects of the Earth system, such as the interactions with radiation, clouds, meteorology, and biogeochemistry, the uncertainties associated with these aerosols are the largest contributor to our inability in understanding and accurately interpreting the Earth’s changing climate. To reduces these aerosols uncertainties, our group's research focuses on two main aerosol species - the mineral dust aerosols and smoke aerosols. We do so because mineral dust and smoke aerosols are the main absorbing aerosols in the atmosphere, and their absorption of solar radiation could offset, in part, the cooling effect associated with anthropogenic aerosols and potentially add to the warming effect already associated with greenhouse gases. As such, our group's research strives to ask fundamental questions that can give deeper insights into how these aerosols works, and help us better understand and constrain their impact on Earth system. Broadly, our group's research can broadly be categorize as follows:
Atmospheric aerosol can directly scatter and absorb the radiation from the sun and the Earth's surface. Whether the scattering and absorption of radiation by a particular aerosol type warm or cool the climate depends on the environmental conditions and the aerosol properties. These aerosol properties include, in part, its abundance in the atmosphere, the distribution of its size and shape, and mineralogical composition.
Our group's research focuses on obtaining better constraints for these aerosol properties, and as such, obtaining a more accurate estimate of their impacts on the Earth's system. In addition, our group's research also seeks to understand other ways aerosols can semi-directly adjust the radiative budget in the atmosphere, such as whether the aerosol layer is above, within, or below the cloud layer.
Atmospheric aerosols can also interact with clouds, serving as cloud condensation and ice nucleation sites upon which liquid droplet or ice particles can form. Our group is interested in how these cloud interactions with dust and smoke aerosols change cloud cover and precipitation distributions both in warm and cold environments
Mineral dust and smoke aerosols can absorb shortwave radiation, warm the nearby atmosphere and change its dynamical and thermodynamical state. Our group strives to understand and better characterize this relationship between aerosols and meteorology so as to get a more accurate picture of aerosol impacts on the Earth system.