摘要
使用高空、地面观测资料、地面自动站雨量资料和美国国家环境预报中心(NCEP)再分析资料,通过水汽通量诊断分析、后向轨迹模型等方法,分析了昆仑山北麓和田地区2020年5月5—7日(简称“05·06”过程)和2021年6月14—17日(简称“06·15”过程)两次极端暴雨过程的环流形势、中尺度系统、水汽输送和收支特征。结果表明:(1)两次暴雨过程有共同的特点:影响系统都为中亚低涡,均有来自里海、咸海一带的水汽输送;对流层低层偏东急流作用显著,最强水汽辐合集中在700~850 h Pa。(2)两次暴雨过程也有明显差异:“05·06”过程的南亚高压为带状分布,水汽输送路径为西方和偏东路径,其中西方路径水汽输送最明显,西边界水汽输入贡献占88%;“06·15”过程的南亚高压为双体型,水汽输送路径为北方和偏南路径,水汽来自阿拉伯海和孟加拉湾的偏南气流向北输送,南方路径输送量远远大于其他路径,南边界水汽输入贡献占78%。(3)和田大气可降水量(PW)增大尤其是超过平均状态时,对强降水出现有指示意义,当PW≥20 mm以上时,可能会出现暴雨或极端暴雨天气。
On the basis of the meteorological observation data and the National Centers for Environmental Prediction reanalysis data and using water vapor flux diagnosis analysis and the hybrid single-particle lagrangian integrated trajectory model,two extreme rainstorms that occurred on May 5—7,2020(the“05·06”rainstorm),and June 14—17,2021(the“06·15”rainstorm),in the Hotan Prefecture,Xinjiang in the north slope of Kunlun Mountains,China were analyzed to study the transport mechanism of water vapor and its budget in the process.The results revealed that(1)the influence system of the two rainstorms was the Central Asian vortex,and they both received water vapor from the Caspian Sea and Aral Sea.During the two rainstorms,there was a clear easterly jet in the lower troposphere,and the strongest water vapor convergence was at the level of 700-850 h Pa.(2)The difference between the two rainstorms was that in the“05·06”rainstorm,the South Asia High was banded.Its water vapor transport path was from the west and east,and mainly from the west,because the west path contributed 88%of the total water vapor transport.However,in the“06·15”rainstorm,the South Asia High was bimodal.Its water vapor transport path was from the north and south,and mainly from the south,which contributed 78%of the total water vapor transport.(3)The southerly flow from the Arabian Sea and Bay of Bengal transported water vapor to the north.When the atmospheric precipitable water in the Hotan region increases,particularly exceeding the average state,heavy precipitation may occur.Rainstorm or extreme rainstorm is more likely to occur when the precipitable water is≥20 mm.
作者
李海花
闵月
李桉孛
李如琦
LI Haihua;MIN Yue;LI Anbei;LI Ruqi(Xinjiang Meteorological Observatory,Urumqi 830002,Xinjiang,China)
出处
《干旱区地理》
CSCD
北大核心
2022年第3期715-724,共10页
Arid Land Geography
基金
第二次青藏高原综合科学考察研究项目(2019QZKK0102)
国家重点研发计划项目(2019YFC1510501)资助。
关键词
极端暴雨
昆仑山北麓
水汽源地
水汽输送
水汽收支
extreme rainstorm
north slope of Kunlun Mountains
water vapor source
water vapor transport
vapor budget