Tropical Pacific Decadal Variability Induced by Nonlinear Rectification of El Niño–Southern Oscillation
Tropical Pacific Decadal Variability Induced by Nonlinear Rectification of El Niño–Southern Oscillation
复制标题
厄尔尼诺-南方涛动非线性校正引起的热带太平洋年代际变化
DOI：
10.1175/jcli-d-19-0123.1
复制
发表时间：
2019
影响因子：
4.9
通讯作者：
J. Kug
中科院分区：
文献类型：
--
作者：
Geon;J. Kug
在32个长期模拟的基础上，我们研究了热带太平洋年代际变率(TPDV)与厄尔尼诺-南方涛动(ENSO)的关系。在耦合模式中，11年移动海面温度(SSTs)的第一经验正交函数(EOF)模通常具有类厄尔尼诺(El Niño)的年代际变化特征，并伴随着海气相互作用。然而，第二个EOF模可以分为两类：1)一些模式具有纬向偶极子SST模式；2)其他模式具有经向偶极子模式的特征。我们发现，与其他模式相比，具有第二模纬向偶极子模式的模式倾向于模拟较强的ENSO振幅和不对称性。同时，定义为El Niño和La Niña SST综合异常的残差型与年代际偶极子型非常相似，表明ENSO残余型可以引起偶极子年代际变化。结果表明，在这些模式中，ENSO变率的年代际调制强烈地依赖于偶极子年代际变率的相位。ENSO残差的年代际变化与偶极子模式的年代际变化有很好的对应关系，ENSO异常的非线性动力加热项与年代际偶极子模式有很好的匹配。
On the basis of 32 long-term simulations with state-of-the-art coupled GCMs, we investigate the relationship between tropical Pacific decadal variability (TPDV) and El Niño–Southern Oscillation (ENSO). The first empirical orthogonal function (EOF) mode for the 11-yr moving sea surface temperatures (SSTs) in the coupled models is commonly characterized by El Niño–like decadal variability with Bjerknes air–sea interaction. However, the second EOF mode can be separated into two groups, such that 1) some models have a zonal dipole SST pattern and 2) other models are characterized by a meridional dipole pattern. We found that models with the zonal dipole pattern in the second mode tend to simulate strong ENSO amplitude and asymmetry in comparison with those of the other models. Also, the residual patterns, which are defined as the summation of El Niño and La Niña SST composite anomalies, are very similar to the decadal dipole pattern, which suggests that ENSO residuals can cause the dipole decadal variability. It is found that decadal modulation of ENSO variability in these models strongly depends on the phase of the dipole decadal variability. The decadal changes in ENSO residual correspond well with the decadal changes in the dipole pattern, and the nonlinear dynamic heating terms by ENSO anomalies are well matched with the decadal dipole pattern.
影响因子：
4.6
作者：
Dommenget, Dietmar;Bayr, Tobias;Frauen, Claudia
通讯作者：
Frauen, Claudia