Polarimetric Radar Observations of the Persistently Asymmetric Structure of Tropical Cyclone Ingrid
Polarimetric Radar Observations of the Persistently Asymmetric Structure of Tropical Cyclone Ingrid
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DOI：
10.1175/2007mwr2077.1
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发表时间：
2008-02
影响因子：
3.2
通讯作者：
P. May;J. Kepert;T. Keenan
中科院分区：
文献类型：
--
作者：
P. May;J. Kepert;T. Keenan
热带气旋英格丽德（Ingrid）平行于澳大利亚北部达尔文市（Darwin）极化气象雷达附近的延伸海岸线并经过时，具有明显的非对称反射率结构和近海极大值。在热带气旋中，首次使用偏振气象雷达微物理分析来识别眼壁上广泛存在的霰和雨雹混合物。整体的微物理结构与其他一些由研究飞机采样的不对称风暴相似。环境剪切和陆海界面均对非对称性有显著贡献，但其相对贡献尚未确定。当风暴在一个半岛和提维群岛之间的开阔海域上移动时，切向风速也发生了非常迅速的变化。10 m s−1变化的时间尺度约为1 h。观测到的雨带也有两种不同的类型：嵌入d的大尺度主带。
Abstract Tropical Cyclone Ingrid had a distinctly asymmetric reflectivity structure with an offshore maximum as it passed parallel to and over an extended coastline near a polarimetric weather radar located near Darwin, northern Australia. For the first time in a tropical cyclone, polarimetric weather radar microphysical analyses are used to identify extensive graupel and rain–hail mixtures in the eyewall. The overall microphysical structure was similar to that seen in some other asymmetric storms that have been sampled by research aircraft. Both environmental shear and the land–sea interface contributed significantly to the asymmetry, but their relative contributions were not determined. The storm also underwent very rapid changes in tangential wind speed as it moved over a narrow region of open ocean between a peninsula and the Tiwi Islands. The time scale for changes of 10 m s−1 was of the order of 1 h. There were also two distinct types of rainbands observed—large-scale principal bands with embedded d...