云南两次灾害性特大暴雨不稳定机制的对比分析  

Contrastive analysis of instability mechanism of two extra torrential rain events in Yunnan Province

作　　者：朱莉[1] 张腾飞[1] 丁治英[2] 

机构地区：[1]云南省气象台,云南昆明650034 [2]南京信息工程大学大气科学学院,江苏南京210044

出　　处：《自然灾害学报》2015年第2期178-185,共8页Journal of Natural Disasters

基　　金：国家自然科学基金项目(41265001);中国气象局预报员专项(CMAYBY2015-070);国家重点基础研究计划项目(2013CB430103);云南省气象局预报员技术开发专项(YB201102)

摘　　要：将NCEP 1°×1°格点资料作为初始场,应用MM5(V3.6)中尺度数值模式对位于我国低纬度高原云南的两次典型的局地特大暴雨个例进行了数值模拟。使用模式输出的高时空分辨率资料绘制了T-ln P图,计算了LI指数、CAPE指数、CIN指数、相当位涡(EPV)等物理量,对云南两次局地特大暴雨个例的条件不稳定性、对流不稳定性以及条件性对称不稳定性进行了分析。研究表明:两次局地特大暴雨个例的不稳定机制各不相同,当层结稳定、对流稳定或弱不稳定时,条件性对称不稳定也会引发强降水。1° × 1°NCEP reanalyzed data and MM5V3. 6 numerical model were used to simulate two typical local extra torrential rain events happened in Yunnan Province which located in lower latitude plateau of china. High space-time resolution data from MM5V3. 6 numerical model was utilized to draw T-ln P diagram and calculate LI index,CAPE index,CIN index and equivalent potential vortex(EPV). These physical quantities were used to analyze the conditional instability,convective instability and conditional symmetrical instability of the two local extra torrential rain events. Results indicate that,the two local extra torrential rain events have different instability mechanism.When atmosphere is stratification stable and convective stable or weak unstable,the conditional symmetrical instability may lead to heavy precipitation.

关 键 词：灾害性特大暴雨 数值模拟 条件不稳定 对流不稳定 条件性对称不稳定 

分 类 号：P458.121.1[天文地球—大气科学及气象学]