DOI: 10.1002/2015MS000543
Scopus记录号: 2-s2.0-84959465316
论文题名: The impact of vertical shear on the sensitivity of tropical cyclogenesis to environmental rotation and thermodynamic state
作者: Zhou W
刊名: Journal of Advances in Modeling Earth Systems
ISSN: 19422466
出版年: 2015
卷: 7, 期: 4 起始页码: 1872
结束页码: 1884
语种: 英语
英文关键词: Boundary layers
; Entropy
; Hurricanes
; Shear flow
; Storms
; Thermodynamic properties
; Thermodynamics
; Tropics
; Cloud resolving simulations
; Coriolis parameter
; Precession process
; Rapid intensification
; Thermodynamic state
; Tropical cyclogenesis
; Tropical cyclone
; Vertical wind shear
; Vortex flow
; atmospheric convection
; boundary layer
; cyclogenesis
; polar vortex
; precession
; rotation
; simulation
; thermodynamics
; tropical cyclone
; wind shear
英文摘要: The impact of vertical wind shear on the sensitivity of tropical cyclogenesis to environmental rotation and thermodynamic state is investigated through idealized cloud-resolving simulations of the intensification of an incipient vortex. With vertical shear, tropical cyclones intensify faster with a higher Coriolis parameter, f, irrespective of the environmental thermodynamic state. The vertical shear develops a vertically tilted vortex, which undergoes a precession process with the midlevel vortices rotating cyclonically around the surface center. With a higher f, the midlevel vortices are able to rotate continuously against the vertical shear, leading to the realignment of the tilted vortex and rapid intensification. With a lower f, the rotation is too slow such that the midlevel vortices are advected away from the surface center and the intensification is suppressed. The parameter, χb, measuring the effect from the low-entropy downdraft air on the boundary layer entropy, is found to be a good indicator of the environmental thermodynamic favorability for tropical cyclogenesis in vertical shear. Without vertical shear, tropical cyclones are found to intensify faster with a lower f by previous studies. We show this dependency on f is sensitive to the environmental thermodynamic state. The thermodynamical favorability for convection can be measured by χm, which estimates the time it takes for surface fluxes to moisten the midtroposphere. A smaller χm not only leads to a faster intensification due to a shorter period for moist preconditioning of the inner region but also neutralizes the faster intensification with a lower f due to enhanced peripheral convection. © 2015. The Authors. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/75960
Appears in Collections: 影响、适应和脆弱性 气候变化与战略
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作者单位: Program in Atmospheric and Oceanic Sciences, Princeton University, Princeton, NJ, United States
Recommended Citation:
Zhou W. The impact of vertical shear on the sensitivity of tropical cyclogenesis to environmental rotation and thermodynamic state[J]. Journal of Advances in Modeling Earth Systems,2015-01-01,7(4)