摘要
使用高空和地面定时观测资料、区域站降水资料、云图和NCEP 1°×1°再分析资料,对2011年6月15—16日敦煌暴雨的影响系统、干侵入、垂直涡度收支、视热源和视水汽汇进行了分析。结果表明:这次暴雨是中高纬度天气系统与低纬度天气系统相互作用,在敦煌附近上空形成中尺度涡旋造成的结果。在低涡生成初期,低涡南侧对流层高层有明显的干侵入发生;低涡快速发展期,干侵入达到最强;对流层中下层辐散作用项对垂直涡度正贡献最大,在对流层中层水平平流项和垂直输送项对垂直涡度正贡献起主要作用;低涡成熟期,干侵入开始减弱。对流层下层辐散作用项对垂直涡度正贡献进一步加强,对流层中层水平平流项正贡献作用减弱,垂直输送项正贡献作用增强。视热源与视水汽汇加热强度变化与低涡发生、发展的不同阶段紧密相关,视热源、视水汽汇中心与垂直上升运动中心相对应,说明大气加热与大气上升运动密切相关,水汽凝结潜热释放加速垂直上升运动,垂直输送在视热源、视水汽汇中起主要作用。
In this paper,the synoptic situation,dry intrusion,vorticity budget,apparent heat source and apparent moisture sink of a rainstorm occurred in Dunhuang during June 15-16,2011 were analyzed using the sounding and surface meteorological data,satellite cloud images and reanalyzed data of NCEP 1°×1°.The results show that the rainstorm was caused by an interaction of the mid-high-latitude weather system and a low-latitude weather system.During the genesis of vortex,dry intrusion occurred in upper troposphere on the south side of the vortex.During the rapid development of the vortex,the dry intrusion was the strongest.During the maturity of the vortex,dry intrusion began to wane.During the rapid development of the vortex,the contribution of horizontal divergence term was the highest for the vertical vorticity in low troposphere,however,horizontal advection term and vertical transmission term played a main role in middle troposphere.During the maturity of the vortex,effect of horizontal divergence term in low troposphere and vertical transmission term in middle troposphere were enhanced,however,the effect of horizontal advection term in middle troposphere was weakened.The negative center of vertical velocity corresponded to the heating center of apparent heat source and apparent moisture sink.These indicated that atmospheric heating and ascending motion were closely coupled,and the condensed latent heat release was the main heat source.
出处
《干旱区研究》
CSCD
北大核心
2013年第1期56-66,共11页
Arid Zone Research
基金
高原低涡切变线在河西走廊极端降水中的作用机制及预报方法研究(甘肃省气象局气象科研项目2013-10)
冰雹云CIN-RAD/CD雷达预警及防雹作业指挥系统集成应用(CAMGJ2012M52)共同资助
关键词
暴雨
高原低涡
干侵入
对流层
垂直涡度
非绝热加热
敦煌
rainstorm
plateau vortex
dry intrusion
troposphere
vorticity budget
diabatic heating
Dunhuang
