造成北京连续高温的河套高压结构分析  

A CASE STUDY OF THE STRUCTURE OF THE HETAO HIGH WHICH CAUSED LONG-LASTING HOT WEATHER IN BEIJING

作　　者：钱婷婷[1] 王迎春[2] 郑祉芳[2] 郑永光[1] 

机构地区：[1]北京大学物理学院大气科学系,暴雨与洪涝灾害实验室,北京100871 [2]北京城市气象研究所,北京100089

出　　处：《应用气象学报》2005年第2期167-173,共7页Journal of Applied Meteorological Science

基　　金：北京市科委项目H020620190091;自然科学基金项目40233036;40305004973项目2004CB418300资助。

摘　　要：就2000年7月11～14日北京连续4天≥35℃的高温天气,分析了与之相关的700hPa河套高压的水平和垂直结构,指出它是与我国西部干旱区大范围暖空气东移相关联的一个深厚的负涡度系统。由于河套高压是一个水平尺度较小的移动性系统,所以高温持续天数较短。作为一个暖性高压,河套高压所对应的负涡度系统在垂直方向可达到对流层上层。极锋急流出口区和副热带急流入口区的高空辐合机制使位于南北两条急流之间的河套高压为下沉运动控制,它所伴随的晴空区辐射增温和绝热增温有利于高温天气的形成。文章最后提出了河套高压的形成还可能和高空急流的动力加压有关。Based on the severe hot weather case taken place on July 11-14, 2000 in Beijing, we analysed the horizontal and vertical structure of the Hetao High on 700hPa associated with the hot weather. The result shows that the High is a deep negative vorticity system and related with a large-scale, eastward moving warm air mass in western arid region. The Hetao High is a relatively small and locomotive system, so hot weather usually sustains only several days.As a warm high, the Hetao High reached the high level of troposphere in vertical direction. Located between the exit region of Polar-front jet and the entrance region of subtropical jet, the upper level convergence makes Hetao High under the control of downward current. Adiabatic warming because of sinking and radiation heating are in favor of hot weather. At last, the paper pointed out that the formation of the Hetao High might be associated with dynamically pressure increase.

关 键 词：高压 结构分析 北京 2000年7月 高温天气 西部干旱区 副热带急流 垂直结构 垂直方向 运动控制 高空急流 系统 相关联 暖空气 大范围 移动性 水平尺 对流层 涡度 增温 上层 辐合 极锋 

分 类 号：P468.2[天文地球—大气科学及气象学]