The QBO–MJO Connection: A Possible Role for the SST and ENSO
The QBO–MJO Connection: A Possible Role for the SST and ENSO
复制标题
QBO 与 MJO 的联系：SST 和 ENSO 的可能作用
DOI：
10.1175/jcli-d-23-0031.1
复制
发表时间：
2023
影响因子：
4.9
通讯作者：
Kang, Wanying
中科院分区：
文献类型：
--
作者：
Randall, David A.;Tziperman, Eli;Branson, Mark D.;Richter, Jadwiga H.;Kang, Wanying
我们研究的假设，观测到的平流层准两年振荡（QBO）和马登-朱利安振荡（MJO）的强度之间的联系调制的海表温度（SST）-例如，厄尔尼诺-南方涛动（ENSO）。综合分析表明，全球范围内，拉尼娜SST与QBO东风阶段发生的SST非常相似。一个最大的协方差分析表明，MJO功率和SST强烈联系在ENSO时间尺度和QBO时间尺度。我们分析模拟与社区地球系统模型的第2版的修改后的配置，具有较高的顶部和精细的垂直分辨率。该模式能够模拟ENSO、QBO和MJO。该模式的海洋耦合版本模拟了QBO，ENSO和MJO，但没有模拟观察到的QBO-MJO连接。然而，当根据QBO东部和QBO西部（QBOE和QBOW）的复合材料，用规定的观测SST异常驱动时，相同的大气模型在QBOE期间相对于QBOW产生了MJO功率的适度增强。我们探讨了海温异常是由QBO本身强迫的可能性。事实上，基于观测的复合霍夫默勒图显示了QBO纬向风异常从平流层上部一直传播到地面。此外，次表层海洋温度复合材料揭示了拉尼娜和QBOE之间的西太平洋和印度洋次表层信号之间的相似性。
We examine the hypothesis that the observed connection between the stratospheric quasi-biennial oscillation (QBO) and the strength of the Madden–Julian oscillation (MJO) is modulated by the sea surface temperature (SST)—for example, by El Niño–Southern Oscillation (ENSO). A composite analysis shows that, globally, La Niña SSTs are remarkably similar to those that occur during the easterly phase of the QBO. A maximum covariance analysis suggests that MJO power and SST are strongly linked on both the ENSO time scale and the QBO time scale. We analyze simulations with a modified configuration of version 2 of the Community Earth System Model, with a high top and fine vertical resolution. The model is able to simulate ENSO, the QBO, and the MJO. The ocean-coupled version of the model simulates the QBO, ENSO, and MJO, but does not simulate the observed QBO–MJO connection. When driven with prescribed observed SST anomalies based on composites for QBO east and QBO west (QBOE and QBOW), however, the same atmospheric model produces a modest enhancement of MJO power during QBOE relative to QBOW, as observed. We explore the possibility that the SST anomalies are forced by the QBO itself. Indeed, composite Hovmöller diagrams based on observations show the propagation of QBO zonal wind anomalies all the way from the upper stratosphere to the surface. Also, subsurface ocean temperature composites reveal a similarity between the western Pacific and Indian Ocean subsurface signal between La Niña and QBOE.