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Title: The Influence of Vertical Wind Shear on the Evolution of Mountain-Wave Momentum Flux
The influence of vertical shear on the evolution of mountain-wave momentum fluxes in time-varying cross-mountain flows is investigated by numerical simulation and analyzed using ray tracing and the WKB approximation. The previously documented tendency of momentum fluxes to be strongest during periods of large-scale cross-mountain flow acceleration can be eliminated when the cross-mountain wind increases strongly with height. In particular, the wave packet accumulation mechanism responsible for the enhancement of the momentum flux during periods of cross-mountain flow acceleration is eliminated by the tendency of the vertical group velocity to increase with height in a mean flow with strong forward shear, thereby promoting vertical separation rather than concentration of vertically propagating wave packets.  more » « less
Award ID(s):
1545927
PAR ID:
10086604
Author(s) / Creator(s):
 ;  
Publisher / Repository:
American Meteorological Society
Date Published:
Journal Name:
Journal of the Atmospheric Sciences
Volume:
76
Issue:
3
ISSN:
0022-4928
Page Range / eLocation ID:
p. 749-756
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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