摘要
１９９７年北半球主要环流特征为：５００ｈＰａ西太平洋副热带高压盛夏由弱转强、西伸明显、脊线位置偏北；亚洲中纬度经、纬向环流交替出现，纬向环流盛行，春、秋季经向环流加强，冬、夏季冷空气异常偏弱；盛夏南海季风增强，印度季风偏弱；赤道辐合带偏弱。北半球１００ｈＰａ中低纬度位势高度持续偏高，南亚高压东扩明显；热带海洋出现异常，一次新的厄尔尼诺事件发生，强度大、发展快。在ＥＮＳＯ和大气环流的共同影响下我国天气气候发生明显异常。
General circulation featrues over the Northern Hemisphere in 1997 are analysed. It is shown that the subtropical high over the west Pacific turns stronger, and extends to the west, and at the same time moves northward in the midsummer. At 500hPa, zonal circulation is dominant in the middle latitude of Asia in the most time of the year. Meridinal circulation strengthen during the spring and autumn. Cold air is weaker than normal during the winter and summer. Monsoon over the South China Sea is stronger than normal, monsoon over India is weaker than normal in the midsummer. ITCZ over the west Pacific is werker than normal. At 100hPa, the geopotential height at the mid low latitude is above normal. The location of the South Asia High is farther to the east than normal. A new El Nino event took place in the tropical Pacific region in 1997. the anomaly of both the tropical Pacific and atmosphere circulation exerted a significant impact on the weather and climate in China.
出处
《气象》
CSCD
北大核心
1998年第4期16-21,共6页
Meteorological Monthly
关键词
北半球
大气环流
环流特征
气候
季风
generral circulation\ the subropical high\ climate\ monsoon\ El Nino
