Short‐Duration Extreme Precipitation in Future Climate

PI: Yanping Li, University of Saskatchewan 

Co-I's: Francis Zwiers, PCIC, University of Victoria; Jean-Pierre St Maurice, University of Saskatchewan

Understanding of the physical processes affecting short‐duration (less than 24 hours) extreme precipitation and their possible changes in the warming world is critical for many of GWF’s users. However, most global and regional climate models do not directly simulate the processes that produce extreme precipitation due to their coarse resolutions, which hinders the proper interpretation of the precipitation projections produced by these models. Such questions can be addressed by making extensive use of a convection‐permitting modeling tool running in a pseudo‐global warming mode, and comparing it with existing simulations by global and regional climate models. Here we propose to work specifically on the following four questions: i) Does temperature scaling work at convective‐permitting resolutions for short‐duration local precipitation extremes? ii) How will the characteristics of mesoscale convective systems (MCSs) such as the precipitation intensity, size, and life‐span of storms change in the future? iii) What are the underlying physical processes that result in changes in MCSs and storm properties? iv) How do extreme precipitation features scale across resolution from GCMs to RCMs to convective permitting WRF? Our proposed work will lead to a better understanding of the physical soundness of future precipitation projections by climate models, thereby providing a scientific foundation for the proper use of model projections that many GWF’s users depend on.