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Seminar coordinator for AY 2017-2018: Prof. Ryan Sriver (rsriver@illinois.edu)

 

Global Variability of Intense Convection

Event Type
Seminar/Symposium
Topic
graduate
Sponsor
Department of Atmospheric Sciences, University of Illinois
Location
Room 114 of the Transportation Building
Date
Oct 16, 2013   3:00 pm  
Speaker
Professor Robert Houze, Department of Atmospheric Sciences, University of Washington
Contact
Shirley Palmisano
E-Mail
sjpalm@illinois.edu
Phone
217-244-5737
Views
867

The A-Train and TRMM satellites have made it possible to analyze deep convection over the globe in detail. This talk will examine the behavior of the most intense convective systems around the globe as seen by these satellites. From the A-Train satellites, we have developed an objective method for identifying and characterizing mesoscale convective systems (MCSs) by combining infrared, passive microwave, and cloud radar data. Less wide and more isolated systems maximize over tropical landmasses. Larger, sometimes interconnected, mesoscale systems with wider and deeper anvil clouds occur prominently over warm tropical oceans. TRMM radar data provide more details of how deep MCSs vary over the tropics and subtropics. We have developed a methodology for using the TRMM radar data to identify different types of intense echoes, namely, those with deep convective towers, those with wide intense convective regions, and those with broad stratiform echo regions. Using these echo-type categories, we show how the population of intense convection varies relative to topography such as the Andes and Himalayas. They further allow us to determine how large-scale circulation features such as the Madden-Julian Oscillation, the Asian monsoon, and the African easterly jet control the convective population characteristics. We use precipitation estimates from the TRMM radar to determine the relative importance of each category of convective storm to climatological rainfall in key areas of the tropics and subtropics.

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