摘要: |
利用自动站资料、探空资料、NCEP再分析资料以及雷达资料,对2016年6月26日浙西地区一次由列车效应引发的暴雨过程进行诊断分析。结果表明:暴雨产生于中低层暖切及地面低压环流的背景场中,降水的增大对应于500hPa以下湿度条件的显著增加和800hPa以下垂直上升速度的维持。中低层西南风风速的增加和暖平流的加强对水汽的输送和暖式切变的增强产生有利的影响,是降水增大的重要原因之一。中尺度Barnes滤波显示强降水区域有中尺度辐合线作用,配合该区域有正涡度和水汽通量辐合的持续作用,使得中尺度辐合线上不断有降水云系产生,同时引导气流方向与低层辐合线走向基本一致从而诱发列车效应,是本次强降水产生的主要原因。 |
关键词: 暴雨 Barnes滤波;中尺度辐合 列车效应 |
DOI: |
投稿时间:2017-10-17修订日期:2018-07-03 |
基金项目:国家自然科学41575047资助 |
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Analysis of a heavy rainfall process caused by train effect |
Lan jun qian |
(Quzhou Meteorology Bureau) |
Abstract: |
This paper uses automatic station data, sounding data, NCEP reanalysis data and radar data to analyze and diagnose the heavy rainfall process caused by train effect in western Zhejiang Province on June 26. The results show that the heavy rainfall occurred in the background field of the middle-low layer warm wind shear and the surface low pressure circulation. The increase of precipitation corresponds to the significant increase of humidity below 500hPa and the maintenance of vertical ascending velocity below 800hPa.The increase of southwest wind velocity and the enhancement of warm temperature advection have a favorable effect on the transport of water vapor and the enhancement of warm wind shear, which is one of the important reasons for the increase of precipitation.Barnes mesoscale wave filter shows mesoscale convergence line combined with positive vortex and water vapor flux have effect on the strong rain area,which makes mesoscale convergence line continuing to produce rain clouds.The occurrence of train effect attributed to the direction of the guiding airflow and the low level convergence line is basically the same,and that is the main reason for this heavy rainfall. |
Key words: heavy rainfall;Barnes wave filter;mesoscale convergence;train effect |