一次弱天气背景下极端短时强降水过程的风廓线雷达分析  

Wind Profiler Radar Analysis of an Extremely Short Time Strong Precipitation Process under Weak Weather Background

作　　者：张东方 张涛 成青燕 韦玮 ZHANG Dongfang;ZHANG Tao;CHENG Qingyan;WEI Wei(Chengdu Meteorological Service,Chengdu 610000,China)

机构地区：[1]四川省成都市气象局,成都610000

出　　处：《高原山地气象研究》2023年第3期99-105,共7页Plateau and Mountain Meteorology Research

基　　金：成都市气象局重点课题(2022-1(3));中国气象局复盘总结专项(FPZJ2023-112);高原与盆地暴雨旱涝灾害四川省重点实验室科技发展基金项目(SCQXKJYJXZD202308)。

摘　　要：基于风廓线雷达、多普勒天气雷达和分钟级自动气象站观测资料,分析了2022年8月3日成都一次极端短时强降水过程中水平风、垂直速度、大气折射率结构常数、低空急流指数和垂直风切变的演变特征,探讨了风廓线雷达对短时强降水天气的应用。结果表明:(1)此次极端短时强降水是在弱天气背景、本地水汽条件好的条件下,由低层东风脉动触发的降水效率极高的暖云降水。(2)风廓线雷达组网资料能够捕捉到大气环流中小尺度的变化,对本次短时强降水的发生及落区有较好的短临预报意义。(3)风廓线雷达测得的风场变化较降水发生时间更早,对降水预报有较好的指示价值。(4)垂直速度和大气折射率结构常数能够很好地反映降水的发生和结束。(5)低空急流指数和垂直风切变在降水发生前40 min出现明显增大。Based on the observation data of wind profiler radar,Doppler weather radar and minute-level automatic weather station,the evolution characteristics of horizontal wind,vertical velocity,atmospheric refractive index structure constant,low-level jet index and vertical wind shear during an extreme short-term heavy rainfall process in Chengdu on August 3,2022 were analyzed,and the application of wind profiler radar to short-term heavy rainfall weather was discussed.The results show that:(1)The extreme short-term strong precipitation is a warm cloud precipitation with high precipitation efficiency triggered by the low-level easterly pulsation under the weak weather background and good local water vapor conditions.(2)The wind profiler radar network data can capture the small and medium-sized changes in the atmospheric circulation,which has a good short-term and imminent forecast significance for the occurrence and falling area of this short-term heavy precipitation.(3)The change of wind field measured by wind profiler radar is earlier than that of precipitation,which has a good indication for precipitation forecast.(4)The vertical velocity and atmospheric refractive index structure constant can well reflect the occurrence and the end of precipitation.(5)The low-level jet index and vertical wind shear increase significantly 40 minutes in advance before precipitation.

关 键 词：短时强降水 垂直速度 大气折射率结构常数 低空急流 垂直切变 

分 类 号：P458.3[天文地球—大气科学及气象学] P412.25