HR: 12:05h
AN: A12A-06 [Abstracts]
TI: Tropical cyclogenesis: The unique perspective
of satellite imagery and scatterometry
AU: * Dunkerton, T J
EM: tim@nwra.com
AF: NorthWest Research Associates, 14508 NE 20th St, Bellevue, WA 98007-3713
United States
AB:
The uniquely valuable perspective of hurricanes afforded by satellite imagery in infrared, visible, and water vapor bands has
been appreciated by operational forecasters for several years but is only beginning to be used for quantitative purposes in
the study of tropical cyclogenesis. The imagery provide a view of the top side of these systems and, in the case of
geostationary imagery, temporal resolution sufficient to witness the lifecycle of individual deep convective clouds as well
as organized convective structures. A weakness of satellite imagery is the inability to see through clouds all the way to the
surface, where the most important dynamics of tropical cyclones and cyclogenesis occur. This deficiency is remedied by a
complementary use of scatterometry and synthetic aperture radar to visualize the detailed structure of vortical and
convective footprints on the sea surface. In this talk, I describe a novel combined use of cloud and sea surface imagery,
together with standard meteorological information of actual storms, that enables a quantitative evaluation of the critical
dynamical and thermodynamical processes that must take place in order for a tropical storm to develop from a background
distribution of vorticity anomalies into a tropical depression and beyond. Examples of mature systems are also highlighted.
These results demonstrate the importance of the satellite perspective for oceanic regions which are data-sparse but extremely
important to monitor owing to the socio-economic implications of hurricane landfall.
DE: 3314 Convective processes
DE: 3329 Mesoscale meteorology
DE: 3354 Precipitation (1854)
DE: 3374 Tropical meteorology
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005