Oscillations in wind speed and temperature are commonly observed in the atmospheric surface layer due to the ubiquitous presence of submeso‐scale motions (SSMs). These motions are of particular importance during stable and low‐wind conditions as their amplitudes are large compared with the background turbulence. We characterize both SSMs and turbulence by utilizing a universal feature of the Eulerian autocorrelation function (EAF) called the negative lobe. The negative lobe is the first negative minimum in the EAF and occurs when an oscillation is present in the signal. A novel analytic formulation of the EAF allows for the representation of both turbulence and SSMs over all atmospheric conditions. This is accomplished by taking into account the separation of scales between turbulence and SSMs. In addition to SSMs during stable conditions and for weak winds, large‐amplitude oscillations are also observed during moderate to high winds. These oscillations are caused by large‐scale turbulent structures known as longitudinal streaks and are correctly represented by the new theory. Due to the general applicability of the new theory, it is possible to develop a new and improved understanding of SSMs and turbulence.

中文翻译：

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大气表层亚尺度尺度运动和湍流表征的一般理论

由于普遍存在亚中尺度运动（SSM），因此通常在大气表层观测到风速和温度的振荡。这些运动在稳定和低风条件下尤为重要，因为它们的振幅比背景湍流大。我们利用欧拉自相关函数（EAF）的普遍特征（称为负波瓣）来表征SSM和湍流。负波瓣是EAF中的第一个负最小值，当信号中出现振荡时就会出现。EAF的新颖分析公式可表示所有大气条件下的湍流和SSM。这是通过考虑湍流和SSM之间的水垢分离来实现的。除了在稳定条件和弱风下的SSM之外，在中高风时也观察到大振幅振荡。这些振荡是由大型湍流结构（称为纵向条纹）引起的，并由新理论正确表示。由于新理论的普遍适用性，有可能发展出对SSM和湍流的新的和更好的理解。