HR: 0800h
AN: A21B-0740    [Abstracts]
TI: Stratospheric Ozone Heating and the Downward Reflection of Forced Planetary Waves
AU: * Nathan, T
EM: trnathan@ucdavis.edu
AF: University of Califormia, Davis, One Shields Avenue, Atmospheric Science Program, Davis, CA 95616 United States
AU: Cordero, E
EM: cordero@met.sjsu.edu
AF: San Jose State University, One Washington Square, Department of Meteorology, San Jose, CA 95192 United States
AB: Forced planetary waves extend throughout the troposphere and stratosphere and thus provide an important link between these two regions of the atmosphere. Although it is well established that vertically propagating planetary waves generated in the troposphere play a major role in driving the zonal-mean stratospheric circulation, an ever-growing body of evidence shows that the stratosphere, despite its lesser mass, may play a more important role in influencing the tropospheric circulation than previously thought. Here we examine the role of stratospheric ozone heating due to wave-ozone feedbacks in the downward reflection of tropospherically generated planetary waves. Using coupled equations for quasigeostrophic potential vorticity and ozone volume mixing ratio, a WKB analysis yields an analytical expression that shows how coupled wave-ozone interactions in the stratosphere can affect the index of refraction and reflection coefficient of topographically forced planetary waves. The reflection coefficient shows explicitly how key stratosphere features, including wind structure, radiative processes and zonal-mean ozone distribution, can affect the planetary wave structure in the troposphere. The analytical results have been confirmed numerically using climatological distributions of wind, temperature and ozone for each season. The numerical results show that depending on the height of the stratospheric reflecting surface, which is a strong function of season, the wave-ozone feedbacks can alter the planetary wave fluxes in the troposphere by as much as 10-15%. These results are discussed in light of stratospheric ozone perturbations arising from solar variability.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0340 Middle atmosphere--composition and chemistry
DE: 0341 Middle atmosphere--constituent transport and chemistry (3334)
DE: 0399 General or miscellaneous
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting