On the Similarity of Lower-Stratospheric Potential Vorticity Dipoles above Tropical and Midlatitude Deep Convection
On the Similarity of Lower-Stratospheric Potential Vorticity Dipoles above Tropical and Midlatitude Deep Convection
复制标题
热带与中纬度深对流上层低平流层位涡偶极子的相似性
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
S. M. Rowe
中科院分区：
文献类型：
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作者：
M. Hitchman;S. M. Rowe
深对流对对流层上部和平流层下部（UTLS）位涡结构影响的模拟表明，在环境水平涡存在的情况下，一个共同的信号是水平位涡偶极子。利用威斯康星州非静力模式系统（UWNMS），对热带气旋塔拉斯和温带“超级星期二”气旋UTLS中对流场与位涡结构的关系进行了研究。UTLS中的位温偶极子被解释为上升气流（冷）上的环境气流向上偏转，然后在背风面（暖）下沉，与风向一致。发现了大于±20 PV单位（1 PVU = 10−6 K kg−1 m2 s−1）的PV偶极子，典型的垂直和水平范围分别为~3 km和~200 km，寿命可达12 h。与Chagnon和Gray的研究结果相一致，发现水平PV偶极子与涡旋倾斜有关，其中水平PV偶极子与涡旋倾斜有关。
AbstractSimulations of the effects of deep convection on the structure of potential vorticity (PV) in the upper troposphere and lower stratosphere (UTLS) have shown that a common signature in the presence of ambient horizontal vorticity is a horizontal PV dipole. Here, the relationship between convection and PV structures in the UTLS in Tropical Cyclone Talas and the extratropical “Super Tuesday” cyclone is investigated with the University of Wisconsin Nonhydrostatic Modeling System (UWNMS). Dipoles of potential temperature in the UTLS are interpreted as an upward deflection of the ambient flow over the updraft (cold), followed by subsidence in its lee (warm), aligned with the wind direction. PV dipoles larger than ±20 PV units (1 PVU = 10−6 K kg−1 m2 s−1) are identified, with typical vertical and horizontal extents of ~3 and ~200 km, respectively, and lifetimes up to 12 h. Confirming the findings of Chagnon and Gray, it is found that horizontal PV dipoles are related to vortex tilting, where horizontally...
影响因子：
8.9
作者：
J. Chagnon;S. Gray;J. Methven
通讯作者：
J. Chagnon;S. Gray;J. Methven