Weather Regimes, Low-Frequency Oscillations, and Principal Patterns of Variability: A Perspective of Extratropical Low-Frequency Variability
Weather Regimes, Low-Frequency Oscillations, and Principal Patterns of Variability: A Perspective of Extratropical Low-Frequency Variability
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天气状况、低频振荡和主要变率模式：温带低频变率的视角
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发表时间：
1999
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影响因子：
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通讯作者：
M. Kimoto
中科院分区：
文献类型：
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作者：
Hisanori Itoh;M. Kimoto
摘要 使用准地转模型在具有真实北半球地形的球体上研究温带低频变率 (LFV) 的动力学基础。该模型由牛顿弛豫驱动至轴对称辐射平衡温度。使用该模型的两个版本：一种具有两个垂直级别和水平 T15 分辨率，另一种具有五个级别和 T21 分辨率。作者在之前的研究中发现，前一个模型在模型参数的稳定范围内具有多个吸引子，并且在不稳定参数集的吸引子废墟中不规则地徘徊。对于更高分辨率的模型也发现了类似的行为。本文考虑了 LFV 的三个方面。前两种是间歇性出现准稳态天气状况和低频振荡。第三个是一些主要变异模式的主导地位，这些模式显示出类似红噪声的时间行为。在真实的气氛中...
Abstract The dynamical basis of extratropical low-frequency variability (LFV) is investigated using a quasigeostrophic model on a sphere with realistic Northern Hemisphere topography. The model is driven by Newtonian relaxation to an axisymmetric radiative equilibrium temperature. Two versions of the model are used: one with two vertical levels and horizontal T15 resolution and the other with five levels and T21 resolution. In previous investigations, by the authors, the former model has been found to possess multiple attractors in a stable range of the model parameters and to wander irregularly among attractor ruins for unstable parameter sets. A similar behavior is found for the higher-resolution model as well. Three aspects of LFV are considered in this paper. The first two are intermittent appearances of quasi-stationary weather regimes and low-frequency oscillations. The third is the dominance of a few principal patterns of variability that show red noise–like temporal behavior. In the real atmospher...