【报告简介】    

The Madden-Julian Oscillation (MJO) is a pattern of intense rainfall and associated planetary-scale circulations in the tropical atmosphere, with a recurrence interval of 30-90 days. It is still a challenge to simulate the MJO in climate models, which is mainly due to our poor understanding on moist convection—deep cumulus clouds and thunderstorms. In this presentation, I will combine observation, modeling, and theory to address the following questions. What is the nature of the MJO? What determines its propagation speed and horizontal scale? How does the MJO respond to climate changes? Our findings challenge previous paradigms, which average over the small scales and focus on the large-scale structure of the MJO. We also point to ways for improving the climate models.