夏季太平洋低纬地区季风环流与信风环流一种可能的连接机制

THE MECHANISM JOINING THE MONSOON CIRCU-LATION TO THE TRADE WIND CIRCULATION OVER THE PACIFIC LOW-LATITUDES DURING SUMMER SEASON

摘要:

北半球夏季太平洋低纬地区的平均经向环流,西部(150°E以西)为季风环流;中部和东部(170°W以东)为信风区的Hadley环流;150°E—170°W之间为季风环流与信风环流的连接区或过渡区。连接季风环流与信风环流的水平环流系统,在高层为太平洋中部热带对流层高层槽(TUTT),低层为强大的太平洋副热带高压。太平洋中部高空槽区就是季风环流与信风环流的连接区或过渡区。本文分析了高空槽的流场结构,并根据各层水平环流和各经度带的垂直环流给出了太平洋低纬地区的三维气流分布示意图。

Abstract:

The general situation of longitudinal circulations over the Pacific low-latitude region of the northern hemisphere during summer, exhibits that to the west of 150°E there is the monsoon circulation, and to the east of 170°W there is the obvious trade circulation. From 150°E to 170°W lies a region of joining or transition between the monsoon and trade circulation. The horizontal circulation systems between the monsoon and the trade are the tropical upper tropos-pheric trough(TUTT)in the upper and the Pacific subtropical high in the lower. The dominent region of TUTT would be the joining or transition zone betweenthe monsoon and trade circulations.In this paper the structure of TUTT was analysed emphatically. Based on the vertical and horizontal circulations over the Pacific area, three-dimensional air-flow picture was given.