非典型环流形势下天津一次局地暴雨过程中尺度特征分析  

Analysis on the mesoscale characteristics of a local rainstorm event under atypical circulation situation in Tianjin

作　　者：张楠[1] 何群英[1] 刘彬贤[1] 吴振玲[1] 刘一玮[1] 卢焕珍[1] ZHANG Nan;HE Qunying;LIU Binxian;WU Zhenling;LIU Yiwei;LU Huanzhen(Tianjin Meteorological Observatory,Tianjin 30007)

机构地区：[1]天津市气象台,天津300074

出　　处：《暴雨灾害》2018年第3期230-237,共8页Torrential Rain and Disasters

基　　金：国家自然科学基金项目(41575049;41675046;41475050);中国气象局预报员专项(CMAYBY2016-006;CMAYBY2017-005);天津市气象局重点项目(201723zdxm04)

摘　　要：利用EC再分析资料、VDRAS资料以及多种观测资料,对2014年8月16日天津地区非典型环流形势下局地暴雨过程的中尺度特征进行分析。结果表明:(1)在对流发生前,偏东气流将海上暖湿空气输送到天津上空,使得天津上空大气水汽含量突增,为短时强降水的发生提供充足的水汽条件;(2)天津西侧雷暴在近地面形成辐散气流,向天津地区输送干冷平流形成干线,当锋生扰动向东推进时,与来自渤海湾的暖湿气流相遇,加强了扰动,触发了天津城区附近对流的发展;(3)干线在东移过程中,与正在向北推进的阵风锋在天津东南部的水汽大值区相碰,且阵风锋以南的中尺度急流为短时强降水的发生提供了源源不断的水汽,使强降水的进一步发展;(4)近地层冷暖空气的交汇,配合中低层气旋式切变,为降水发展的动力机制。Based on EC reanalyzed data, VDRAS data, and a variety of observations, the mesoscale characteristics of a local rainstorm event under atypical circulation situation happened in Tianjin on 16 August 2014 were discussed. The results are as follows.（1） Before the convection occurred, the easterly transported warm air to Tianjin, which makes the atmospheric moisture contents over Tianjin increased suddenly,providing sufficient water vapor condition for the occurrence of the short time heavy precipitation.（2） There was a divergence airflow at boundary layer on the west side of Tianjin, which led to the formation of dry line.When the frontogenesis disturbance moved eastward, it met with the warm air from the Gulf of Bohai.The disturbance then became stronger, triggering the convection near the area of Tianjin City.（3） When the dry line moved eastward, the gust front interacted moist region in the southeast of Tianjin. Additionally, water vapor transport provided by meso-scale low-level jet stream further enhanced the development of heavy precipitation.（4） The intersection between the cold and warm air masses near surface with the cyclonic shear at low level is a favorable dynamic mechanism for the development of precipitation.

关 键 词：局地暴雨 干线 锋生扰动 边界层辐合线 水汽输送 

分 类 号：P458.121.1[天文地球—大气科学及气象学]