Can Air Pollution Fuel Extreme Weather Events and Contribute to Long-Term Climate Changes ? (Invited Talk) (Invited Presentation)

Being major agent of air pollution, aerosols have potentials to influence a range of weather variables. They can also alter the earth’s climate by altering energy and water cycles. Considering the high concentration of human population, pollution and the economic productivity in urban areas, aerosol-induced changes in any extreme weather events could have important social and economic implications. This talk will be focused on the impact over densely populated regions on such extreme event as heavy rainfall, thunderstorms, lightning on different time scales ranging from diurnal cycle, weekly cycle to decadal changes. The impact may result from a single aerosol effect or a combination of numerous effects pending on meteorological regimes and aerosol properties. In the most polluted region in eastern China, for example, a continual trend of air quality deterioration in the last a few decades may have played a significant role to the climate changes in the region, but it is extremely challenging to sort out and quantify those caused by natural variability and human-induced air quality, let alone to attribute quantitatively each contribution. On the other hand, the nearly exponential increase in aerosol related studies since 1990s has tremendously advanced our understanding of this important topic, for it is a major missing puzzle in solving the mystery of earth’s climate change. The core of my talk is concerned with aerosol-radiation-interaction and aerosol-cloud-interaction effects and feedbacks between aerosol, stability, dynamics, microphysics and topography.