2007年夏季我国深对流活动时空分布特征  

Distribution and Spatiotemporal Variations of Deep Convection over China and Its Vicinity During the Summer of 2007

作　　者：祁秀香[1,2] 郑永光 

机构地区：[1]国家气象中心,北京100081 [2]南京信息工程大学江苏省气象灾害重点实验室,南京210044

出　　处：《应用气象学报》2009年第3期286-294,共9页Journal of Applied Meteorological Science

基　　金：国家重点基础研究发展计划(2004CB418300);国家自然科学基金项目(40875019);2005年江苏省"六大人才高峰"项目共同资助。

摘　　要：利用逐时FY-2C卫星红外亮温(T_(BB))资料讨论了2007年夏季(6—8月)我国深对流活动的时空演变特征,并同10年的深对流活动特征进行了对比分析。从Y_(BB)≤-52℃统计特征来看,2007年夏季我国大陆深对流活动主要集中在4个区域:华南沿海地区,青藏高原,云贵高原东部及四川、重庆,江淮流域。我国中东部地区深对流日际变化特征表明:不同月份深对流分布特征不同,深对流活动具有明显的间歇性、波动性特征。对比10年T_(BB)≤-52℃统计结果来看,2007年夏季深对流日变化具有如下异常特征:华南地区深对流具有午后发展特征;青藏高原深对流活动持续时间明显短于10年统计结果,并且东传特征不明显;贵州东部、四川东北部山区、湖北西部山区、山东丘陵地带、江淮流域与华北平原深对流日变化表现出明显的多峰特征;江淮流域深对流日变化具有明显的向东传播特征。The large-scale persisting rainstorm, extremely heavy precipitation and severe convective events result in tremendous damage in economy and severe personnel casualty during the summer of 2007. Based on FY- 2C hourly infrared TBB dataset from June to August in 2007, the distribution and spatiotemporal variations of deep convection over China and its vicinity during the summer of 2007 is analyzed and compared with the atmospheric circulation background based on the NCEP final analysis dataset and the climatological distribution of deep convection based on 10-year TBB dataset. The statistical characteristics of TBB less than --52℃ show that there are four active deep convection areas over China during the summer of 2007. South China seaside, the Tibetan Plateau, the Yunan-Guizhou Plateau, Sichuan Province together with Chongqing City and the Yangtze Huaibe River Basin. The daily variations of deep convection over Central and East China show that the deep convection distribution is very different in different months, and the deep convection activity has an obviously fluctuating feature. The active deep convection areas are farther south and are located to the south of 30°N in June, and the active deep convection areas advance to the north of 40°N in July, however, the active deep convection areas retreat to the south of 25°N in August. The characteristics of the daily variations of deep convection are close associated with the evolution of the large-scale atmospheric circulation. The deep convection over the Tibetan Plateau and the Yunnan-Guizhou Plateau has one active peak and lasts longer time in the diurnal variations, but the deep convection over the Sichuan Basin and Chongqing City has a nocturnal characteristic and develops in the early morning. Comparing with the 10-year statistical results of TBB less than --52 ℃, there are some characteristics different from the 10-year results. First, the deep convection over South China occurrs more frequently in the afternoon than those in the 10-year statistical

关 键 词：深对流 红外亮温 时空分布 

分 类 号：P458.2[天文地球—大气科学及气象学]