AXA Award Research Project: Global Patterns of Extreme Precipitation

DESCRIPTION: Prof. Sobel and several colleagues, at the Fu Foundation School of Engineering and Applied Sciences (FFSEAS) and Lamont-Doherty Earth Observatory (Lamont), will use the award to study the local dynamics and global patterns of extreme precipitation and other extreme weather events. The first component will examine the dynamical mechanisms controlling extreme precipitation. This work will build upon previous work in tropical atmosphere dynamics, in which the weak temperature gradient (WTG) approximation has been used with parameterized or cloud-resolving models of deep convection. The project will extend this work to incorporate large-scale dynamical forcing, as is usually implicated in truly major flooding events such as Pakistan 2010 or Southeast Asia in 2011. The second component of the project will look at global patterns of variability in a range of extreme event types, including tropical cyclones, tornadoes, and others. The essential question here will be whether there are patterns of variability in extreme events, perhaps associated with major climate modes such as El Nino/Southern Oscillation (ENSO) or others, which are more predictable than extreme events at any one location are. Besides being of basic scientific interest, this question is relevant to any application in which the extreme events dispersed across the globe can have an impact. Examples could include international disaster relief or reinsurance.

OUTCOMES: Developed column quasi-geostrophic method to model interaction of convection and large-scale dynamics in extreme precipitation events. Applied to 2010 Pakistan Flood.