7 May (CLIM) Foufoula-Georgiou, Global Precipitation Extremes

Efi Foufoula-Georgiou, U California, Irvine 

Precipitation in the Earth System: 

Global estimation, precipitation extremes relevant to hazards, and climate change 

Wed, 7 May, 1:30pm 

Innovation 134 and via Zoom (for link, email bklinger@gmu.edu) 

Host: Jagadish Shukla 

Under global warming, precipitation is expected to change in complex ways, including the frequency and magnitude of extremes.  I will present recent results on: (1) global precipitation estimation from multi-satellite observations in places lacking ground measurements, and (2) assessment of the change of the space-time structure of storms under global warming.  We combine instantaneous Passive Microwave (PMW) satellite snapshots with the dynamical temporal information provided by GEO IR satellites, to capture extremes and provide uncertainty quantification.  We analyze the cold-season precipitation over the western United States in the WRF model at 6 km and 1 h resolution in the historical period and pseudo-future simulations under the high emission RCP8.5 scenario. We demonstrate that global warming will induce a “sharpening” of storms both in time and space, meaning that a larger proportion of rain will fall over fewer wet hours and over smaller areas, amplifying hazard potential for flooding and post-fire debris flows.