Xiaowen Li - 613 Seminar Series

Morgan State University

Big aerosol events dominate the news: volcano eruptions, forest fires, dust storms, biomass burning, big city pollution… We have too much of it in our air! Or do we? Aerosol has a relatively short lifetime and its geographic distributions are inhomogeneous. The aerosol concentrations can be very low at places such as in the ocean interiors. In this talk, we will use cloud-resolving model simulations to explore how aerosol, serving as cloud condensation nuclei (CCN), modulates convection intensity. We will show that marine background aerosol could produce, in average, weaker convection in the tropics compared with high aerosol scenarios. I will propose a theory to link aerosol concentrations to strengths of tropical convection and propagations of the Madden-Julian Oscillation. There will be many “holes” in my attempt to stretch from the scale of microns (aerosols) to thousands of kilometers (convectively coupled planetary waves). You are welcome to tear at these “holes”. I promise I shall not spoil your fun.