近18年青海不同类型强降水关键对流参数特征对比  

Comparison of Key Convective Parameter Characteristics of Classified Heavy Precipitation in Qinghai in the last 18 Years

作　　者：苏永玲[1,2] 李剑婕 王有莲 廖淑君 胡垚 Su Yongling;Li Jianjie;Wang Youlian;Liao Shujun;Hu Yao(Qinghai Meteorological Station,Xining 810001,China;Sichuan Key Laboratory of Heavy Rainfall,Drought and Flood Disasters in Plateau and Basin,Chengdu 610072,China)

机构地区：[1]青海省气象台,西宁810001 [2]高原与盆地暴雨旱涝灾害四川省重点实验室,成都610072

出　　处：《青海科技》2024年第5期150-156,共7页Qinghai Science and Technology

基　　金：青海省重点研发与转化项目“青海省高影响天气智能网格预报技术研究和应用”(2023-SF-111);高原与盆地暴雨旱涝灾害四川省重点实验室开放基金项目“高原低涡影响下短时强降水环境特征研究”(SZKT202109)。

摘　　要：利用2004—2021年5—9月50个国家自动站统计出的青海145站次短时强降水个例,根据环流形势分3类,统计对比不同类型下强降水发生前能量、水汽、不稳定、动力等关键对流参数特征,以期提高此类强对流天气预报预警能力。分析结果表明:(1)青海145个短时强降水根据环流形势可分为西风气流型55个、低涡切变型43个、副热带高压型47个,其中西风气流型主要分布在青海东部农业区,低涡切变型集中分布在青南地区,副热带高压型中心分布在35.5°N并向南北递减。(2)西风气流型具有最高的对流有效位能和对流抑制能量、动力强迫条件;低涡切变型需要较大的不稳定层结度条件即沙氏指数、最大抬升指数及700 hPa与500 hPa温差或600 hPa与400 hPa温差。西风气流型和低涡切变型可产生伴雷暴大风、冰雹等混合性的强对流天气;副热带高压型具有较高的水汽条件,产生以短时强降水为主的强对流天气。Using the 145 cases of short-term heavy precipitation in Qinghai counted by 50 national automatic stations during May-September from 2004 to 2021,which were classified into three categories according to the circulation situation,the characteristics of key convective parameters such as energy,water vapor,instability,and dynamics before the occurrence of heavy precipitation of different types were statistically compared,aiming to deepen the understanding of the characteristics of convective parameters of different types of heavy precipitation in Qinghai and to improve the forecasting and warning capability for this type of strong convective weather.The results showed that:(1)The 145 short-duration heavy precipitation events in Qinghai could be divided into 55 westerly flow-type,43 low vortex shear-type,and 47 subtropical high-pressure-type according to the circulation situation.The heavy precipitation of westerly flow-type was mainly distributed in the eastern agricultural area of Qinghai,the heavy precipitation of low vortex shear-type was centrally distributed in the south of Qingnan area,and the center of the heavy precipitation of subtropical high-pressure-type was distributed at 35.5°N and decreases to the north and south.(2)The heavy precipitation of westerly flow-type had the highest convective effective potential energy and convective suppression energy.The heavy precipitation of low vortex shear-type required larger unstable layer junction conditions,namely,Shah’s index,the maximum lifting index,and the temperature difference between 700hPa and 500hPa or 600hPa and 400hPa.The heavy precipitation of both westerly flow-type and low vortex shear-type could produce mixed strong convective weather with thunderstorms,gusty winds,and hail.The heavy precipitation of subtropical high-pressure-type,with higher water vapor conditions,resulted in strong convective weather dominated by short-term heavy precipitation.

关 键 词：青海 环流分型 短时强降水 对流参数 

分 类 号：P426.6[天文地球—大气科学及气象学]