Observations and Numerical Simulations of Inertia–Gravity Waves and Shearing Instabilities in the Vicinity of a Jet Stream
Observations and Numerical Simulations of Inertia–Gravity Waves and Shearing Instabilities in the Vicinity of a Jet Stream
复制标题
急流附近惯性重力波和剪切不稳定性的观测和数值模拟
DOI：
10.1175/jas3305.1
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发表时间：
2004
影响因子：
3.1
通讯作者：
R. Sharman
中科院分区：
文献类型：
--
作者：
T. Lane;J. Doyle;R. Plougonven;M. Shapiro;R. Sharman
利用美国国家海洋和大气管理局GulfstreamIV研究飞机的观测资料和数值模拟，研究了2001年2月18日在强急流/高空锋系统附近产生的惯性重力波的特征和动力学。飞机空投探空仪观测和数值模拟详细阐明了该系统的中尺度结构，包括其相关的惯性-重力波和晴空湍流。多重嵌套数值模型的结果显示，在发展中的射流/锋面系统上方，惯性-重力波发展。这些惯性重力波在急流上方的高度剪切气流中传播，扰乱了背景风切变和稳定性，并形成了理查森数减少或增加的带。这些减少理查德森数的波段可能是开尔文-亥姆霍兹不稳定的区域，也是观测到的晴空湍流的可能来源。
The characteristics and dynamics of inertia‐gravity waves generated in the vicinity of an intense jet stream/ upper-level frontal system on 18 February 2001 are investigated using observations from the NOAA GulfstreamIV research aircraft and numerical simulations. Aircraft dropsonde observations and numerical simulations elucidate the detailed mesoscale structure of this system, including its associated inertia‐gravity waves and clearair turbulence. Results from a multiply nested numerical model show inertia‐gravity wave development above the developing jet/front system. These inertia‐gravity waves propagate through the highly sheared flow above the jet stream, perturb the background wind shear and stability, and create bands of reduced and increased Richardson numbers. These bands of reduced Richardson numbers are regions of likely Kelvin‐Helmholtz instability and a possible source of the clear-air turbulence that was observed.