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Pfister et al. 1993
Pfister, L., Chan, K.R., Bui, T.P., Bowen, S., Legg, M., Gary, B., Kelly, K., Proffitt, M. and Starr, W. (1993). Gravity waves generated by a tropical cyclone during the STEP tropical field program: A case study. Journal of Geophysical Research 98: doi: 10.1029/92JD01679. issn: 0148-0227.

Overflights of a tropical cyclone during the Australian winter monsoon field experiment of the Stratosphere-Troposphere Exchange Project (STEP) show the presence of two mesoscale phenomena: a vertically propagating gravity wave with a horizontal wavelength of about 110 km and a feature with a horizontal scale comparable to that of the cyclone's entire cloud shield (wavelength of 250 km or greater). The larger feature is fairly steady, though its physical interpretation is ambiguous. The 110-km gravity wave is transient, having maximum amplitude early in the flight and decreasing in amplitude thereafter. Its scale is comparable to that of 100-to 150-km-diameter cells of low satellite brightness temperatures within the overall cyclone cloud shield; these cells have lifetimes of 4.5 to 6 hours. Aircraft flights through the anvil show that these cells correspond to regions of enhanced convection, higher cloud altitude, and upwardly displaced potential temperature surfaces. A three-dimensional transient linear gravity wave simulation shows that the temporal and spatial distribution of meteorological variables associated with the 110-km gravity wave can be simulated by a slowly moving transient forcing at the anvil top having an amplitude of 400-600 m, a lifetime of 4.5-6 hours and a size comparable to the cells of low brightness temperature.

The forcing amplitudes indicate that the zonal drag due to breaking mesoscale transient convective gravity waves is definitely important to the westerly phase of the stratopause semiannual oscillation and possibly important to the easterly phase of the quasi-biennial oscillation. There is strong evidence that some of the mesoscale gravity waves break below 20 km as well. The effect of this wave breaking on the diabatic circulation below 20 km may be comparable to that of above-cloud diabatic cooling. ¿ American Geophysical Union 1993

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Keywords
Meteorology and Atmospheric Dynamics, Middle atmosphere dynamics, Meteorology and Atmospheric Dynamics, Waves and tides, Meteorology and Atmospheric Dynamics, Tropical meteorology, Meteorology and Atmospheric Dynamics, Convective processes
Journal
Journal of Geophysical Research
http://www.agu.org/journals/jb/
Publisher
American Geophysical Union
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