论文标题
通过喷气速度黑暗：在没有喷气速度可变性的情况下，强大的欧洲大西洋制度的出现
Through a Jet Speed Darkly: The Emergence of Robust Euro-Atlantic Regimes in the Absence of Jet Speed Variability
论文作者
论文摘要
通常使用涡流驱动器的纬度或在500HPA地理电位高度（Z500）的相位空间中识别欧洲大西洋制度。但是，尽管在喷气纬度指数中明显明显的三峰性，但Z500簇需要高度敏感的显着性测试，以将它们与自相关噪声区分开。结果，即使被考虑到时间周期的小变化也可以显着改变诊断的制度。修复最佳制度编号也很难证明是合理的。我们认为，这种速度是这种缺乏鲁棒性的来源。一旦消除了影响，Z500相空间就会显然非高斯，聚类算法很容易恢复三个非常稳定的机制，与喷气纬度方案相对应。进一步的分析支持存在与倾斜和拆分射流相对应的另外两个方案。因此，该框架自然会统一两个制度的观点。
Euro-Atlantic regimes are typically identified using either the latitude of the eddy-driven jet, or clustering algorithms in the phase space of 500hPa geopotential height (Z500). However, while robust trimodality is visibly apparent in jet latitude indices, Z500 clusters require highly sensitive significance tests to distinguish them from autocorrelated noise. As a result, even small shifts in the time-period considered can notably alter the diagnosed regimes. Fixing the optimal regime number is also hard to justify. We argue that the jet speed, a near-Gaussian distribution projecting strongly onto the Z500 field, is the source of this lack of robustness. Once its influence is removed, the Z500 phase space becomes visibly non-Gaussian, and clustering algorithms easily recover three extremely stable regimes, corresponding to the jet latitude regimes. Further analysis supports the existence of two additional regimes, corresponding to a tilted and split jet. This framework therefore naturally unifies the two regime perspectives.
