摘要
本文利用23年夏季3个月的500hPa位势高度场，对20°N以北的热带以外地区的位势高度异常进行了分析，着重研究了持续时间超过天气尺度扰动时间（大约1周）的持续异常。结果表明：500hPa高度场上持续异常的产生具有很大的地理依赖性，在以下几个地区最容易产生持续异常：（1）北太平洋中东部到阿拉斯加南部（NEP）。（2）北大西洋东部到欧洲大陆西海岸（EAT）。（3）前苏联西北部的新地岛附近（WNSU）。（4）加拿大北部的哈得逊湾附近（NCA）。（5）白令海峡以北的北冰洋地区（ARC）。进一步对异常关键区统计分析得到：异常多发区特征显著地不同于异常少发区，正异常与负异常也有所差别。
In this paper, we use 500hPa geopotential height to study the abnormal disturbance for the North-ern Hemisphere poleward of 20°N summertime from 1957 to 1979, special focusing on persistent anom-alies which persistent time are longer than that of synoptic scale variability. The results show that occur rences of persistent anomalies have their geographical dependence, and there are high numbers of per-sistent positive anomaly and persistent negative anomaly in the following areas: (1) the northeast of the northern Pacific Ocean to the south of Alaska (NEP), (2) the east of the northern Atlantic to the west coast of Europe (EAT), (3) the northwest of the former Soviet Union (WNSU), (4) the north of Canada (NCA); (5) the Arctic ocean of the north of Bering Strait (ARC). In addition, through analysing the key regional characteristics, we find that the characteristics is obvious different betWeen the areas having high numbers of anomaly and the areas having low numbers of anomaly, the difference between the areas having low numbers of anomaly and persistent negative anomaly also exists.
出处
《大气科学》
CSCD
北大核心
1994年第2期163-172,共10页
Chinese Journal of Atmospheric Sciences
关键词
地理分布
持续异常
位势高度场
geographical distribution, persistent anormaly
persistence, regional characteristics
