Extended Abstract (140K)7C.1
Tropical Cyclones in Complex Vertical Shears
William M. Frank, Penn State University, University Park, PA; and E. A. Ritchie
Simulations of hurricanes in idealized environmental flows are performed using the Penn State/NCAR Mesoscale Model (MM5). This study examines the effects of complex vertical wind shear patterns upon the core structures and intensities of hurricanes. This will include analyses of the effects of directionally varying vertical wind shear and the shear induced by a variable Coriolis parameter.
Previous studies by the authors were performed on an f-plane in environments with imposed unidirectional vertical shear. Those studies showed that vertical wind shear tends to produce rapid and persistent changes in the symmetry of the hurricane core, but that changes in storm intensity lagged the imposition of the shear, often by a day or longer. This paper builds upon the earlier work by examining more complex and realistic environmental shears as well as by performing additional diagnostic analyses of the physical processes by which the environmental shears alter the storm properties.
Session 7C, Tropical Cyclones: Vertical Shear (Parallel with Sessions 7B and 7D)
Tuesday, 30 April 2002, 4:00 PM-5:30 PM
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