An idealized numerical study of tropical cyclogenesis and evolution at the Equator
An idealized numerical study of tropical cyclogenesis and evolution at the Equator
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赤道热带气旋发生和演化的理想化数值研究
DOI：
10.1002/qj.3701
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发表时间：
2020
影响因子：
8.9
通讯作者：
Montgomery MT
中科院分区：
文献类型：
--
作者：
Kilroy G;Smith RK;Montgomery MT
利用理想化的三维模式模拟，从规定的、初始的、微弱的逆时针旋转涡旋开始，在一个静止的、不旋转的环境中，探索赤道或附近热带气旋的形成和演变。进行了三次模拟，其中最大切向风速(5 m S)被指定为初始半径50、100或150 公里。在30~60 小时的孕育期后，涡旋迅速增强，其演变与远离赤道的涡旋相似。特别是，初始涡尺寸越大，孕育期越长，达到的最大强度越大，涡流寿命越长。几天后，随着初始涡旋提供的气旋性涡量源被耗尽，涡核周围的负涡度被对流驱动的翻转环流向内吸引，涡旋开始衰减。在这些负涡度区域，流动是惯性/离心力不稳定的。成熟期和衰退期的涡旋演化与赤道以外的模拟不同，赤道以外的惯性不稳定区的面积要有限得多。模拟中的涡旋衰减似乎与惯性不稳定的发展密切相关，惯性不稳定伴随着向外传播的深对流带。这条深对流带在多大程度上是真实的是未知的。
Tropical cyclone formation and evolution at, or near, the Equator is explored using idealized three‐dimensional model simulations, starting from a prescribed, initial, weak counterclockwise rotating vortex in an otherwise quiescent,nonrotatingenvironment. Three simulations are carried out in which the maximum tangential wind speed (5 m s) is specified at an initial radius of 50, 100, or 150 km. After a period of gestation lasting between 30 and 60 hr, the vortices intensify rapidly, the evolution being similar to that for vortices away from the Equator. In particular, the larger the initial vortex size, the longer the gestation period, the larger the maximum intensity attained, and the longer the vortex lifetime. Beyond a few days, the vortices decay as the cyclonic vorticity source provided by the initial vortex is depleted and negative vorticity surrounding the vortex core is drawn inwards by the convectively driven overturning circulation. In these negative vorticity regions, the flow is inertially/centrifugally unstable. The vortex evolution during the mature and decay phases differs from that in simulations away from the Equator, where inertially unstable regions are much more limited in area. Vortex decay in the simulations appears to be related intimately to the development of inertial instability, which is accompanied by an outward‐propagating band of deep convection. The degree to which this band of deep convection is realistic is unknown.
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影响因子：
8.9
作者：
G. Kilroy;Roger K. Smith
通讯作者：
G. Kilroy;Roger K. Smith
影响因子：
8.9
作者：
Roger K. Smith;M. Montgomery
通讯作者：
Roger K. Smith;M. Montgomery
影响因子：
8.9
作者：
G. Kilroy;Roger K. Smith;M. Montgomery
通讯作者：
G. Kilroy;Roger K. Smith;M. Montgomery
赤道及其附近的热带气旋生成
影响因子：
8.9
作者：
Steenkamp SC;Kilroy G;Smith RK
通讯作者：
Smith RK
与冰过程相关的加热和冷却对热带气旋发生和强化的作用
影响因子：
8.9
作者：
G. Kilroy;R. K. Smith;M. T. Montgomery
通讯作者：
M. T. Montgomery