Interannual oscillatory modes, atmospheric and oceanic, are present in several large regions of the globe. We examine here low-frequency variability (LFV) over the entire globe in the Community Earth System Model (CESM) and in the NCEP-NCAR and ECMWF ERA5 reanalyses. Multichannel singular spectrum analysis (MSSA) is applied to these three datasets. In the fully coupled CESM1.1 model, with its resolution of \(0.1 \times 0.1\) degrees in the ocean and \(0.25 \times 0.25\) degrees in the atmosphere, the fields analyzed are surface temperatures, sea level pressures and the 200-hPa geopotential. The simulation is 100-year long and the last 66 yr are used in the analysis. The two statistically significant periodicities in this IPCC-class model are 11 and 3.4 year. In the NCEP-NCAR reanalysis, the fields of sea level pressure and of 200-hPa geopotential are analyzed at the available resolution of \(2.5 \times 2.5\) degrees over the 68-years interval 1949–2016. Oscillations with periods of 12 and 3.6 years are found to be statistically significant in this dataset. In the ECMWF ERA5 reanalysis, the 200-hPa geopotential field was analyzed at its resolution of \(0.25 \times 0.25\) degrees over the 71-years interval 1950–2020. Oscillations with periods of 10 and 3.6 years are found to be statistically significant in this third dataset. The spatio-temporal patterns of the oscillations in the three datasets are quite similar. The spatial pattern of these global oscillations over the North Pacific and North Atlantic resemble the Pacific Decadal Oscillation and the LFV found in the Gulf Stream region and Labrador Sea, respectively. We speculate that such regional oscillations are synchronized over the globe, thus yielding the global oscillatory modes found herein, and discuss the potential role of the 11-year solar-irradiance cycle in this synchronization. The robustness of the two global modes, with their 10–12 and 3.4–3.6 years periodicities, also suggests potential contributions to predictability at 1–3 years horizons.

年际振荡模式，大气和海洋，存在于全球几个大区域。我们在社区地球系统模型 (CESM) 以及 NCEP-NCAR 和 ECMWF ERA5 再分析中检查了整个全球的低频变化 (LFV)。多通道奇异谱分析 (MSSA) 应用于这三个数据集。在完全耦合的CESM1.1模型中，其分辨率为\(0.1 \times 0.1\)度在海洋和\(0.25 \times 0.25\)度，分析的场是地表温度、海平面压力和 200 hPa 位势。模拟时间长达 100 年，分析中使用了最近的 66 年。该 IPCC 级模型中的两个统计显着周期是 11 年和 3.4 年。在 NCEP-NCAR 再分析中，在1949-2016 年的 68 年间隔内，以\(2.5 \times 2.5\)度的可用分辨率分析了海平面压力场和 200-hPa 位势场。在该数据集中，发现周期为 12 年和 3.6 年的振荡具有统计显着性。在 ECMWF ERA5 再分析中，200 hPa 位势场的分析分辨率为\(0.25 \times 0.25\)在 1950-2020 年的 71 年间获得学位。在第三个数据集中，发现周期为 10 年和 3.6 年的振荡具有统计显着性。三个数据集中振荡的时空模式非常相似。北太平洋和北大西洋上空的这些全球振荡的空间模式分别类似于太平洋年代际振荡和在墨西哥湾流地区和拉布拉多海发现的 LFV。我们推测这种区域振荡在全球范围内是同步的，从而产生了本文发现的全球振荡模式，并讨论了 11 年的太阳辐照度周期在这种同步中的潜在作用。两种全球模式的稳健性（具有 10-12 年和 3.4-3.6 年的周期）也表明对 1-3 年范围内的可预测性的潜在贡献。