本文已被:浏览 307次 下载 2360次
投稿时间:2020-12-27 修订日期:2021-09-28
投稿时间:2020-12-27 修订日期:2021-09-28
中文摘要: 利用河北承德山区自动气象站观测资料、卫星资料、承德CB型多普勒天气雷达探测资料以及NCEP再分析资料,分析了2008—2017年夏季6—8月承德山区146次短时强降水事件,结果表明:夏季承德山区短时强降水的大尺度环流型特征表现为冷涡型的占比最高,达45%,西风槽型次之,占34%,副热带高压(以下简称副高)外围型仅占21%;其中,6月的短时强降水大多发生在冷涡背景下且强降水落区分散,而7月上旬至中旬的短时强降水多受西风槽影响,7月下旬之后转变为副高外围型;副高外围型和西风槽型短时强降水空间分布相似,多集中在承德南缘燕山迎风坡。此外,与华北雨季主要受副高北跳影响不同,承德山区短时强降水集中在6月下旬至7月下旬,且其峰值出现在冷涡和西风槽共同影响期间。产生短时强降水的中尺度对流系统主要从西南(北京东北部)、西北(内蒙古)移入承德区界,另外还有相当一部分承德本地新生的对流风暴。传统雨季以副高外围型为主,其水汽含量较高且存在明显的湿舌,南部山区850 hPa比湿在12 g·kg-1以上,且有较大范围水汽输送,其他流型下的短时强降水过程水汽含量低且水汽输送量不显著,冷涡型850 hPa水汽含量仅为8 g·kg-1。承德山区区域平均大气可降水量中位数值仅为33 mm,冷涡型低至29 mm,即使是副高外围型大气整层可降水量中位数值(38 mm)亦较南侧平原地区低15 mm。承德山区短时强降水发生在层结极不稳定的环境下:冷涡型和西风槽型850 hPa和500 hPa温差中位数值分别为28.6℃ 和27.9℃,而我国其他地区(包括山区)多在25℃以下。
中文关键词: 山区,短时强降水,时空分布,环境参数
Abstract:146 short-time severe precipitation cases in summer (JJA) were selected to analyze the distribution characteristics of short-time severe precipitation in Chengde from 2008 to 2017 based on the multiple data of automatic weather station, meteorological satellite, Doppler radar and NCEP reanalysis. The results show that the synoptic circulation patterns controlling severe precipitation in the Chengde Montains can be divided into the cold vortex type (45%), westerly trough type (34%) and edge of the western Pacific subtropical high (WPSH) type (21%). The short-time severe rainfall in June mostly occurs under the background of cold vortex circulations, with scattered rain falling areas. The dominant circulation pattern in the early-mid July is the westerly trough type but turns to be the edge of WPSH type after the late July. The severe precipitation under both the westerly trough type and the edge of WPSH type are generally distributed on the windward slope of Yanshan Mountain in the southern edge of Chengde. Differing from the traditional rainy season in North China, which is influenced by the position of subtropical high, the concentrated period of the short-term severe precipitation in Chengde is from late June to late July, and the peak appears when the cold vortex and the westerly trough circulations take action together. Mesoscale convective systems which are responsible for short-time severe precipitation move in Chengde mainly through southwest (northeastern Beijing) and northwest (Inner Mongolia) channels. In addition, a considerable number of convective storms are born locally in Chengde. The short-time severe precipitation in Chengde are often along with less water vapor and poor transportation compared with that in conventional rainy season. The water vapor content of cold vortex type is only 8 g·kg-1 at 850 hPa. The median of the area averaged atmospheric precipitable water (PW) is 33 mm in the Chengde Mountains and is only 29 mm under the cold vortex circulation. Even if the median of PW under the edge of WPSH type gets to 38 mm, it is still 15 mm lower than that in the south plain areas. The short-time severe precipitation often occurrs in extremely unstable stratification. The medians of temperature difference between 850 hPa and 500 hPa of cold vortex type and the westerly trough type are 28.6℃ and 27.9℃ respectively, while the others are below 25℃ in most of areas (including mountainous areas) of China.
文章编号: 中图分类号: 文献标志码:
基金项目:国家重点研发计划重点专项(2018YFC1507602)和国家自然科学基金项目(41875058)共同资助
引用文本:
王宏,王秀明,姜云雁,高艳春,杨杰,尤国军,冯钰博,胡琪琭,李兆祺,张宇杰,2021.承德山区夏季短时强降水的时空分布及环境参数特征[J].气象,47(12):1469-1483.
WANG Hong,WANG Xiuming,JIANG Yunyan,GAO Yanchun,YANG Jie,YOU Guojun,FENG Yubo,HU Qilu,LI Zhaoqi,ZHANG Yujie,2021.Spatio-Temporal Distribution and Environmental Parameters of Short-Time Severe Precipitation in the Chengde Mountains in Summer[J].Meteor Mon,47(12):1469-1483.
王宏,王秀明,姜云雁,高艳春,杨杰,尤国军,冯钰博,胡琪琭,李兆祺,张宇杰,2021.承德山区夏季短时强降水的时空分布及环境参数特征[J].气象,47(12):1469-1483.
WANG Hong,WANG Xiuming,JIANG Yunyan,GAO Yanchun,YANG Jie,YOU Guojun,FENG Yubo,HU Qilu,LI Zhaoqi,ZHANG Yujie,2021.Spatio-Temporal Distribution and Environmental Parameters of Short-Time Severe Precipitation in the Chengde Mountains in Summer[J].Meteor Mon,47(12):1469-1483.