HR: 0800h
AN: A51A-0021 [Abstracts]
TI: Precipitation Structures and Atmospheric Waves over the Tropical Ocean
AU: * Swann, A
EM: aswann@atmos.berkeley.edu
AF: Department of Earth and Environmental Sciences,
Lamont Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964
United States
AU: Sobel, A H
EM: ahs129@columbia.edu
AF: Depatment of Applied Physics and Applied Mathematics and Department of Earth and Environmental Sciences,
Columbia University, S.W. Mudd, Room 217, New York, NY 10027
United States
AU: Yuter, S
EM: sandra_yuter@ncsu.edu
AF: Dept. of Marine, Earth and Atmospheric Sciences
North Carolina State University, Campus Box 8208
1125 Jordan Hall, Raleigh, NC 27695
AU: Kiladis, G
EM: George.Kiladis@noaa.gov
AF: NOAA/Aeronomy Laboratory, Aeronomy Laboratory R/AL3
325 Broadway, Boulder, CO 80305-3328
United States
AB:
Propagating disturbances in the tropical atmosphere which exhibit characteristics of linear equatorial waves have been shown
to be ``coupled" to convection. Considering the difference in dynamical characteristics between these equatorial wave types,
it follows that the ``coupled" convective dynamics might differ depending on wave type. Rain events spanning three years at
Kwajalein Atoll, RMI, were classified by associated wave type (i.~e. Kelvin or mixed Rossby--gravity (MRG)) using
space--time spectral--filtered outgoing longwave radiation (OLR). Contoured frequency by altitude diagrams (CFADs) of radar
for the classified dates were compared between the two groups. Kelvin wave--associated rain days show a distinctly different
vertical structure from MRG wave--associated rain days with a significant shift towards smaller reflectivity values at all
heights. The mean rain--rate for Kelvin wave--associated storms was also higher than the MRG events despite a shift towards
smaller reflectivity values. Our observational result suggests that convective dynamics differs significantly between
rainstorms associated with these two different tropical atmospheric wave types.
DE: 0320 Cloud physics and chemistry
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005