Thursdays, 4:00 pm, Workman 101 (unless noted*)
Physics 579 Graduate Seminar
Name: David J. Raymond, NMT
Title: Atmospheric Convection, Weather and Climate
NOTE: Thur, Feb 16, 2016 — Workman 101
Atmospheric moist convection differs from other types of convection in fundamental ways,
the most important of which is the production of precipitation. Though the ascending branch
of a convective cell is typically a few kilometers in diameter, the existence of rainfall causes the
descending branch of the circulation to be spread over thousands of kilometers. This is unlike
most other convection, in which the descending current has roughly the same dimensions
as the ascending current. Atmospheric moist convection is therefore inherently multi-scale,
which causes immense problems in the representation of such convection in global weather
and climate models. Nevertheless, the fundamental role of convection as a large-scale energy
transfer mechanism in the atmosphere is clear.
In tropical regions, atmospheric circulations are dominated by convection, which makes
the tropics an excellent laboratory for studying this phenomenon. Recent modeling and field
observations of tropical convection have led to new insights into the behavior of large-scale
tropical disturbances including tropical cyclones, in which convection plays a crucial role.
How convection changes under the influence of global warming is of great importance to
the atmosphere as a whole. I will discuss current ideas on this subject.