Distinct Effects of Atmospheric Aerosols on Tropical Cyclones

Long-term observations have revealed large amplitude fluctuations in the frequency and intensity of tropical cyclones, but the anthropogenic impacts, including greenhouse gases and particulate matter pollution, remain to be elucidated. In particular, effects of atmospheric aerosols on tropical cyclones are found to be important but quite complex due to many confounding factors at play. In this presentation, the progress in our recent researches will be reviewed to unravel the relative importance of those factors and underlying physical mechanisms by combining process-level modeling (CR-WRF) and satellite observations (TRMM, MODIS, and GOES-R). The key factors identified by our studies include aerosol type (anthropogenic or natural) and properties (scattering or absorptive, CCN or IN), cyclone developing stage (genesis, developing, or mature), aerosol radiative versus microphysical effects, feedbacks from the varying ocean surface conditions, and large-scale dynamical and thermodynamical conditions.