Special CASPO Seminar: Prof. Gary Lackmann, "Low-level jets, potential vorticity, and Atmospheric Rivers"


 
06/19/2019 - 11:00am to 12:00pm
Location: 
101 Nierenberg Hall
Event Description: 

Prof. Gary Lackmann

North Carolina State University

 

AbstractI expect that there is little need to convince this audience of the important societal impacts of heavy
precipitation and flooding! In this talk, I will present research on heavy precipitation events
spanning several decades, with an emphasis on moisture transport mechanisms and atmospheric
rivers (ARs). We will examine case studies from the U.S. West Coast, the South-Central U.S.,
and the U.S. East Coast; these cases feature extratropical cyclones, organized convection, and a
nearby tropical cyclone, respectively. Comparing and contrasting events from different
geographical regions (around North America) and with a diverse set of weather system types
allows us to examine the different mechanisms of moisture transport, and the physical processes
affecting ultimately responsible for it. Despite differences in the geographical setting and in the
precipitation delivery mechanisms, each event features a narrow strip of lower-tropospheric
cyclonic potential vorticity (PV) in association with a low-level jet (LLJ) and band of enhanced
moisture transport (AR) into the heavy precipitation region. Model sensitivity experiments clarify
the role of condensational heating and topography in the production of the lower PV and LLJ. The
results suggest that despite the importance of condensational heating, some AR / LLJ events rely
on this mechanism. If time permits, I’ll discuss the sensitivity of model representation of these
features to resolution and model physics for some of the case studies.

For more information on this event, contact: 
Art Miller
x8033
Event Calendar: 
CASPO