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投稿时间:2019-11-13 修订日期:2020-11-28
投稿时间:2019-11-13 修订日期:2020-11-28
中文摘要: 统计分析了2014—2016年5—10月国家站共出现的219站次有效短时强降水及云南省7部多普勒天气雷达资料,将云南省副热带高压(以下简称副高)外围的短时强降水进一步细分为两高(青藏高压和西太平洋副高)辐合类、单纯副高外围类及副高西侧配合西风槽类。初步得出以下结论:8月为云南省副高外围类短时强降水的高发期且降水时段集中在午后及前半夜;两高辐合类降水沿着辐合区呈显著的带状分布特征,降水强度强、落区相对集中。单纯副高外围类降水主要位于滇南地区,存在三个强降水中心。副高西侧配合西风槽类降水主要位于云南省的边缘地区,落区较为分散;三类降水回波主体平均强度均在35~45 dBz,平均持续9个体扫;近1/4的回波出现回波倾斜及强回波梯度特征,且降水明显强于未出现的回波,一定程度上可以作为判断降水强度的参考依据;三类降水的最强雷达回波顶高及垂直累积液态含水量出现的时间均同最强回波出现的时间基本一致或略有滞后;两高辐合类的垂直风廓线中有近一半的个例在低层存在西南风或西风气流,对应明显的暖平流输送特征。随着降水发展与副高外围晴空区相对应的无资料区的逐渐消失则是单纯副高外围类降水的垂直风廓线表现最为明显的特征。副高西侧配合西风槽类降水开始前后均存在高空西北气流入侵及中层风切变特征,与低槽后部带来的冷平流及冷暖气流交汇相对应。
中文关键词: 副热带高压外围,短时强降水,雷达回波特征
Abstract:Based on the data of effective short-time severe rainfall at 219 national stations and from 7 Doppler weather radars in Yunnan Province from May to October in 2014-2016, the short-time severe rainfall in the periphery of the subtropical high in Yunnan is further subdivided into three categories, including the Qinghai-Tibet high and western Pacific subtropical high convergence category, simple periphery of the subtropical high category and the west side of subtropical high with westerly trough category. The conclusions are as follows. August is the high incidence period of short-time severe rainfall in the periphery of the subtropical high in Yunnan Province, and the precipitation period is concentrated in the afternoon and the first half of the night. The Qinghai-Tibet high and western Pacific subtropical high convergence precipitation distributes along the convergence area, with high intensity and relatively concentrated falling area. The simple periphery of the subtropical high precipitation is mainly located in southern Yunnan, manifested as three large-value zones. The west side of subtropical high with westerly trough precipitation is mainly located at the edge of Yunnan with scattered falling areas. The average intensity of the three types of precipitation echoes is between 35 dBz and 45 dBz with average duration of 9 volume scans. Nearly a quarter of the echoes have inclination and strong echo gradients, and the precipitation is obviously heavier than the echo which does not appear. In a way that can be used as a basis for judging the intensity of precipitation. The occurrence time of the strongest ET and VIL of the three types of precipitation is basically at the same time as that of the strongest echo, or slightly lagged behind. Nearly half of the Qinghai-Tibet high and western Pacific subtropical high convergence VWPs have southwesterly or westerly airflows in the lower layer, which corresponds to the obvious characteristics of warm advection. With the development of precipitation, the disappearance of no-data area corresponding to the clear sky area around the subtropical high is the most obvious feature of VWPs of precipitation in the simple periphery of the subtropical high. For the west side of subtropical high with westerly trough category, whether precipitation begins or not, invasion of upper northwest airflow and middle-level wind shear both exist, corresponding to the cold advection brought by the rear of the low trough and the intersection of warm and cold air currents.
文章编号: 中图分类号: 文献标志码:
基金项目:中国气象局预报员专项(CMAYBY2017-069和CMAYBY2020-121)共同资助
作者 | 单位 |
何钰 | 云南省气象台,昆明 650100 |
陈小华 | 云南省气象台,昆明 650100 |
李耀孙 | 云南省气象台,昆明 650100 |
尹丽云 | 云南省人工影响天气中心,昆明 650100 |
李华宏 | 云南省气象台,昆明 650100 |
引用文本:
何钰,陈小华,李耀孙,尹丽云,李华宏,2021.云南省副热带高压外围类短时强降水的雷达回波特征[J].气象,47(4):450-462.
HE Yu,CHEN Xiaohua,LI Yaosun,YIN Liyun,LI Huahong,2021.Radar Echo Characteristics of Short-Time Severe Rainfall in the Periphery of Subtropical High in Yunnan Province[J].Meteor Mon,47(4):450-462.
何钰,陈小华,李耀孙,尹丽云,李华宏,2021.云南省副热带高压外围类短时强降水的雷达回波特征[J].气象,47(4):450-462.
HE Yu,CHEN Xiaohua,LI Yaosun,YIN Liyun,LI Huahong,2021.Radar Echo Characteristics of Short-Time Severe Rainfall in the Periphery of Subtropical High in Yunnan Province[J].Meteor Mon,47(4):450-462.