当前位置： 首页»科研成果» 2015 李建平与合作者在JOURNAL OF CLIMATE上发表论文 全球院

 

Cheng Sun^1,2 Jianping Li^1,3 Juan Feng^1,2 Fei Xie^1,2

 

1 College of Global Change and Earth System Science (GCESS), Beijing Normal University, Beijing 100875, China

2 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China

3 Joint Center for Global Change Studies, Beijing 100875, China

 

ABSTRACT

The time series of twentieth-century subtropical eastern Australian rainfall (SEAR) shows evident fluctuations over decadal to multidecadal time scales. Using observations from the period 1900–2013, it was found that SEAR is connected to the North Atlantic Oscillation (NAO) over decadal time scales, with the NAO leading by around 15 yr. The physical mechanism underlying this relationship was investigated. The NAO can have a delayed impact on sea surface temperature (SST) fluctuations in the subpolar Southern Ocean (SO), and these SST changes could in turn contribute to the decadal variability in SEAR through their impacts on the Southern Hemisphere atmospheric circulation. This observed lead of the NAO relative to SO SST and the interhemispheric SST seesaw mechanism are reasonably reproduced in a long-term control simulation of an ocean–atmosphere coupled model. The NAO exerts a delayed effect on the variation of Atlantic meridional overturning circulation that further induces seesaw SST anomalies in the subpolar North Atlantic and SO. With evidence that the NAO precedes SEAR decadal variability via a delayed SO bridge, a linear model for SEAR decadal variability was developed by combination of the NAO and Pacific decadal oscillation (PDO). The observed SEAR decadal variability is considerably well simulated by the linear model, and the relationship between the simulation and observation is stable. SEAR over the coming decade may increase slightly, because of the recent NAO weakening and the return of negative PDO phase.

 

PUBLISHED BY: JOURNAL OF CLIMATE, 2015, 28, DOI: 10.1175/JCLI-D-14-00372.1

 

SOURCE: http://journals.ametsoc.org/doi/full/10.1175/JCLI-D-14-00372.1?queryID=14/617626