冬季东亚副热带西风急流变化及其与夏季风环流关系研究.doc

文档介绍：
冬季东亚副热带西风急流变化及其与夏季
风环流关系研究#
况雪源,曹明明*
5
10
15
20
25
30
(南京大学大气科学学院)
摘要:本文利用 NCEP/ NCAR 月平均再分析资料对冬季 200hPa 纬向风场进行 EOF 分解,
探讨东亚副热带西风急流位置和强度变化特征,分析其对后期东亚夏季风的影响,并对影响
机理进行初步探究。研究结果表明冬季东亚副热带西风急流强度变化具有显著的 3~4 年的
年际振荡;急流的南北位移具有 12 年的年代际振荡及 2~3 年的年际振荡周期。相关分析
表明冬季急流的强度及位置异常对后期东亚夏季风的强度变化有显著影响:冬季高空急流偏
强(弱),夏季风偏弱(强);冬季急流位置南移(北移),夏季风偏强(偏弱)。这种影
响是通过冬季风与低纬海气相互作用,从而影响后期夏季风变化而实现的。
关键词:东亚副热带西风急流; 东亚夏季风;SST
中图分类号:P4
Study on the relation between winter East Asian subtropical
westerly jet and summer monsoon systems
Kuang Xueyuan, Cao Mingming
(School of Atmospheric Sciences,Nanjing University)
Abstract: Winter 200hPa zonal wind of NCEP / NCAR reanalysis data is posed by using
EOF method to study the variation of the East Asian subtropical westerly jet in this paper. Its
relationships with the following East Asian summer monsoon systems are further examined. The
results show that the intensity of the East Asian subtropical westerly jet in winter takes significant
3-4 years interannual oscillation while its meridional displacement exhibits 12 years interdecadal
variation and 2-3 years interannual oscillation. Correlation analysis implies that the abnormal
intensity and location of the winter jet can lead to response of the East Asian summer monsoon
systems: Stronger (weaker) intensity of winter jet stream corresponds to weaker (stronger)
summer monsoon; Meanwhile, so