阻塞形势破坏时期的东亚一次寒潮过程

作者对1956年2月下旬的一次东亚寒潮天气,进行了天气学的分析。分析得出,在寒潮爆发的时期,原先维持在大西洋和乌拉尔上空的阻塞高压发生崩溃。北半球的环流型式亦表现有极明显的改变,即从低指数的环流变向高指数的环流。此次寒潮的冷空气源地,一直可以溯源至格林兰东方的北冰洋上。此外,对此次寒潮爆发时期中,东经125度上空急流的结构亦作了分析,我们发现在这个时期中,有两个急流出现——即极锋急流及副热带急流。

A SYNOPTIC AND AEROLOGICAL STUDY ON A COLD WAVE IN THE FAR EAST DURING THE PERIOD OF THE BREAK DOWN OF THE BLOCKING SITUATION OVER EUROASIA AND ATLANTIC

A synoptic and aerological study on a cold wave in the Far East is made during the period of the break down of the blocking situation over Euroasia and Atlantic. It is found that during this period the hemispherical circulation pattern is markedly changed. It is changed from low index pattern into high index pattern. The onset of the cold wave occured during the period of changes. The source of the arctic air for this cold wave may be traced upstream to the Arctic Ocean to the east of Greenland, Furthermore, the structure of the jet streams over 125°E during the cold wave is analysed. Two distinct jet streams-polar front jet and the subtropical jet-were found.