Abstract:
The secular variation of the winter atmosphere circulation teleconnection pattern is studide in this paper.It is shown that Western Atlantic (WA),Pacific/North American (PNA) pattern had clearly trend and interdecadal change.The significant negative trend of the WA intensity index was abserved.however.the intensity of the PNA pattern had positive trend.The abrupt change of their intensity occurred in the early 1980's when WA pattern changed fron strong to weak and in the middle 1970's when PNA pattern changed fron weak to strong,respectively.Almost at the same time,the winter meridional circulation intensity in the area of Asia and Eurasia abruptly weaked in 1983.This interdecadal change of the intensity indices of the atmospheric and teleconnection pattern may be an important reason that causes climatic warming over China in winter.