1982—83年厄尼诺现象与西北太平洋夏季(6—8月)低纬环流特征的初步分析

A PRELIMINERY ANALYSIS ON THE RELATIONSHIP BETWEEN THE TROPICAL CIRCULATION IN SUMMER (JUNE-AUGUST) IN NORTHWEST PACIFIC AND 1982-83 EL-NINO PHENOMENON

摘要:

1982—83年的厄尼诺和南方涛动是本世纪最强的一次ENSO(El-Nino/Southern Oscill-ation)事件。本文分析对比了El-Ni(?)o当年(1982)夏季(6—8月)和El-Nino次年(1983)夏季的西北太平洋低纬度环流特征发现有明显的差异,在1982年夏季,西北太平洋副热带高压明显偏弱;850hPa低纬度西风较强;200hPa上低纬度东风较强,在赤道海洋上已建立了沃克反环流,根据1982年和1983年夏季向外的长波辐射差异图可发现菲律宾以东洋面上ITCZ活跃。而在1983年夏季的低纬度环流几乎与1982年夏季的相反。这两年上述的差异是与赤道太平洋中部或东部的海温异常增暖有关的。

Abstract:

The 1982-83 Ei-Nino/Southern OScillation event(ENSO) was one of the strongest of the century. In this paper the relationship between the tropical circulation in summer (June-August) in North-west Pacific and 1982-83 ENSO event has been anal-yased. It is shown that a weak subtropical high pressure,strong equatorial westerly at 850mb and strong equatorial easterly at 200mb over the Northwest Pacific and the acwalker circulation were established in equatorial ocean, and an active ITCZ was found over eastern ocean from the phillipines on the difference map of OLR (outgoing longwave radiation) for the summer of 1982 and 1983 (1982 minus 1983) during 1982 summer. On the other hand, large-scale summer circulation in 1983 was almost reversed from those of 1982 summer.It is thought that the aformentioned difference in Tropical circulation over Northwest Pacific in 1982 and 1983 summer results from the anomalously warm water in the eastern or central equatorial Pacific.