The Third Roscoe R. Braham seminar is scheduled for October 16, 2017.

Speaker: Professor Sonia Lasher-Trapp, Blue Waters Professor, Department of Atmospheric Sciences, University of Illinois
at Urbana-Champaign

Seminar Title: The COnvective Precipitation Experiment (COPE)

Abstract:  Although it may be surprising to those living outside the United Kingdom, there is a history of destructive, sometimes deadly, flash flood events in Southwest England. Lines of convective storms initiated by sea breeze fronts can be nearly stationary for hours. The storms within the lines can be much more shallow than those seen in the Central U.S., and yet produce very heavy rainfall. This area of the world thus provides a dependable locale to study the details of heavy convective rainfall, knowledge that can be useful in improving model predictions of such events worldwide.

The COnvective Precipitation Experiment (COPE) was held in July and August 2013 in Southwest England, a joint endeavour between UK and U.S. scientists. Several instrumented aircraft, as well as a surface aerosol measurement site and a new UK portable polarimetric radar, were deployed. A variety of numerical weather prediction models were run in real time by the UK Met Office. The U.S contribution to the project included the University of Wyoming King Air with its cloud radar and lidar and suite of microphysical probes, as well as high-resolution numerical modelling studies of entrainment and the possible microphysical pathways of convective precipitation.

The activities and goals are in some ways quite similar to the Thunderstorm Project, from which data were analyzed in detail by Roscoe Braham and others, and led to the first comprehensive views of thunderstorms and their precipitation. In contrast, the COPE and other projects like it have benefitted greatly from over 6 decades of technological and scientific advancement since that time. An overview of observational data analyses and high-resolution numerical simulations from selected COPE cases provide new insight on some of the most important processes for heavy convective rainfall, and where future work is yet needed.