Turbulence Variations in the Upper Troposphere in Tropical Cyclones from NOAA G-IV Flight-Level Vertical Acceleration Data
Turbulence Variations in the Upper Troposphere in Tropical Cyclones from NOAA G-IV Flight-Level Vertical Acceleration Data
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来自 NOAA G-IV 飞行高度垂直加速度数据的热带气旋中对流层上层的湍流变化
DOI：
10.1175/jamc-d-18-0148.1
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发表时间：
2019
影响因子：
3
通讯作者：
Ditchek, Sarah D.
中科院分区：
文献类型：
--
作者：
Molinari, John;Rosenmayer, Michaela;Vollaro, David;Ditchek, Sarah D.
NOAA G-IV 飞机通常通过惯性导航系统以 1 Hz 测量垂直飞机加速度。这些数据提供了 12.8 至 14.8 公里海拔层上 250 米水平尺度的湍流测量结果。该层热带气旋的湍流在半径200公里以内的范围内最大，达到35%~40%，向外到半径1000公里处单调减少。大型飓风的湍流超过了较弱的热带气旋。湍流数据点分为热带气旋的三个区域：卷云冠层；卷云冠层外；以及它们之间的过渡区。无一例外，树冠内的湍流较大，树冠外的湍流较弱。所有半径的夜间湍流都超过了白天的湍流，尤其是在卷云冠层内，这表明辐射强迫是湍流产生的一个因素。对飓风伊万 (2004) 中广泛湍流的案例研究表明，飓风流出通道与北部西风带之间的相互作用在对流层高层形成了一个绝对涡度为 -6 × 10−5s−1 的区域。气流从风暴中心加速进入这个惯性不稳定区域，并且湍流和卷云横向带的明显证据出现在惯性不稳定区域的径向内部。有人认为，云辐射强迫和狭窄流出层内惯性不稳定性的发展是造成湍流的原因。相比之下，第二个案例研究（Isabel 2003）显示在存在大的正绝对涡度并且没有局部惯性不稳定的情况下存在强烈的近核心湍流。湍流峰值发生在眼壁对流顺风 100 公里处。
The NOAA G-IV aircraft routinely measures vertical aircraft acceleration from the inertial navigation system at 1 Hz. The data provide a measure of turbulence on a 250-m horizontal scale over a layer from 12.8- to 14.8-km elevation. Turbulence in this layer of tropical cyclones was largest by 35%–40% in the inner 200 km of radius and decreased monotonically outward to the 1000-km radius. Turbulence in major hurricanes exceeded that in weaker tropical cyclones. Turbulence data points were divided among three regions of the tropical cyclone: cirrus canopy; outside the cirrus canopy; and a transition zone between them. Without exception, turbulence was greater within the canopy and weaker outside the canopy. Nighttime turbulence exceeded daytime turbulence for all radii, especially within the cirrus canopy, implicating radiative forcing as a factor in turbulence generation. A case study of widespread turbulence in Hurricane Ivan (2004) showed that interactions between the hurricane outflow channel and westerlies to the north created a region of absolute vorticity of −6 × 10−5s−1in the upper troposphere. Outflow accelerated from the storm center into this inertially unstable region, and visible evidence for turbulence and transverse bands of cirrus appeared radially inward of the inertially unstable region. It is argued that both cloud-radiative forcing and the development of inertial instability within a narrow outflow layer were responsible for the turbulence. In contrast, a second case study (Isabel 2003) displayed strong near-core turbulence in the presence of large positive absolute vorticity and no local inertial instability. Peak turbulence occurred 100 km downwind of the eyewall convection.
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DOI：
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发表时间：
2009
期刊：
影响因子：
--
作者：
A. Lenz;K. Bedka;W. Feltz;S. Ackerman
通讯作者：
S. Ackerman
影响因子：
3.1
作者：
J. Molinari;Patrick Durán;David Vollaro
通讯作者：
J. Molinari;Patrick Durán;David Vollaro
热带气旋流出层结构和对涡流强迫的平衡响应
DOI：
--
发表时间：
2017
期刊：
影响因子：
--
作者：
Sarah D. Ditchek;J. Molinari;David Vollaro
通讯作者：
David Vollaro
关于斜压圆形涡旋的稳定性：不稳定的充分判据。
DOI：
--
发表时间：
1966
期刊：
影响因子：
--
作者：
K. Ooyama
通讯作者：
K. Ooyama
影响因子：
3.1
作者：
Patrick Durán;J. Molinari
通讯作者：
Patrick Durán;J. Molinari