quantifying entrainment and its effects in isolated, sheared cumuli and thunderstorms

This new NSF award funds the systematic investigation of entrainment in storms that occur in regions with environmental wind shear, the conditions that can sustain supercell thunderstorms. General relationships between wind shear, cumulus entrainment, and convective precipitation will be sought, to ultimately improve prediction of thunderstorm initiation, and rain, hail and lightning that form within these storms. Simulations will be performed on the Blue Waters Supercomputer.


Convective Precipitation Experiment- Microphysical and Entrainment Dependencies (COPE-MED)

In collaboration with Dr. Dave Leon and Prof. Jeff French at the University of Wyoming, and Dr. Alexi Korolev of Environment Canada, we took the Wyoming King Aircraft (containing the Wyoming Cloud Radar and Lidar) to the UK-based COPE experiment in July and August 2013. Our focus is upon how differences in the strength of the warm rain process impact, directly and through ice multiplication, the development of heavy convective precipitation. We are also investigating how entrainment processes alter these microphysical pathways.  This work also involves a collaboration with a number of UK investigators, especially Prof. Alan Blyth of NCAS/Univ. of Leeds.

A Bottom-up Approach to improve the Representation of Deep convective clouds in weather and climate models 

In collaboration with department colleagues Jeff Trapp and Steve Nesbitt, this new DOE-sponsored research is using numerical modeling and observational analysis to investigate factors (including microphysical ones) that influence storm cold pool characteristics that may generate new convective storms. 

A System for Characterizing and Measuring Precipitation (SCAMP)

A collaboration among faculty in the Department of Atmospheric Sciences is the new acquisition of a mobile suite of instruments (SCAMP) desgined to quantitatively characterize the vertical profile of cloud and precipitation particles within storms, measure the particle size distributions and integrated total liquid and frozen precipitation falling from those storms, and document the scavenging of air particulates by the falling precipitation.

The cornerstone of the system is a vertically pointing, Doppler Micro-rain radar. Together with the high-resolution Parsivel2 disdrometer, the DMT Meteorological Particle Spectrometer and a Geonor precipitation guage, we will have the capability to profile the microphysical structure of precipitation from the ground upward to cloud top to understand and interpret its formation, evolution, and relationship to larger-scale storm structure. As precipitation falls, it removes particulates from the air; a TSI Optical Particle Sizer will document changes in air particulates after rainfall or snowfall. Background weather conditions are measured with the Lufft ultrasonic weather station.