2004年7月北京和上海两次重大气象事件的异同及其科学问题

SIMILARITIES AND DIFFERENCES BETWEEN TWO DISASTROUS WEATHER EVENTS OCCURRED IN BEIJING AND SHANGHAI JULY 2004 AND THE AROUSED SCIENTIFIC PROBLEMS (PRIMARY RESEARCH REPORT)

中文关键词:  暴雨  飑线  对流系统  季风  经向环流

英文关键词:Heavy rainfall  Squall line  Convection  Monsoon  Meridional circulation

中文摘要:

      004年7月10日北京市出现的局地强降水导致城区交通严重拥堵,12日强对流伴随的飑线造成上海市重大的人员伤亡。这两次突发性气象事件都引起了社会公众和政府部门的高度关注。文中给出的观测分析和理论估算初步表明,这两次重大气象事件都是由中尺度对流系统(MCS)引起的。但是在卫星云图上,造成北京强降水的对流云团外形不规则、云顶温度较高、云体边缘不光滑并且没有密集的亮温梯度,与大多数MCS有很大的不同。此外,这两个事件都发生在季风极度北涌,同时冷空气又强烈南下的经向环流背景下,但两者发生的位置差别很大。文章认为对于这种非典型性MCS的结构和发生条件以及2004年夏东亚季风极度北涌是否与全球环流异常有关等科学问题值得引起重视。

英文摘要:

      Two disastrous weather events in July 2004,the local heavy precipitation caused the serious traffic jam in Beijing July 10 and a squall line associated with the severe convection caused seven lives loss in Shanghai July 12,turned into the focus of the public and government authority attention.The primary research of observational analysis and theoretical estimation suggested that both of them were caused by meso-β-scale convective systems (MCS).But,the infrared satellite images of GOES shown that the MCS caused heavy precipitation of Beijing had irregular external form,higher temperature of cloud top,un-smooth edge of cloud body,and weak temperature gradient.Those characteristics were different to the normal MCS.Otherwise,both two cases toke place when the large-scale circulation were in verystrong meridional situation and the Asia summer monsoon pushing northward exceedingly too,but the locations of two MCSs occurrence were different considerable.Finally,the scientific problems were suggested which are the internal structure and development conditions of this kind of at ypical MCS,and the relationship between the exceedingly pushing northward of Asia summer monsoon and the global general circulation.