On the Near-Inertial Resonance of the Atlantic Meridional Overturning Circulation
On the Near-Inertial Resonance of the Atlantic Meridional Overturning Circulation
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DOI：
10.1175/jpo-d-13-092.1
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发表时间：
2013-12
影响因子：
3.5
通讯作者：
F. Sévellec;J. Hirschi;A. Blaker
中科院分区：
文献类型：
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作者：
F. Sévellec;J. Hirschi;A. Blaker
大西洋纬向翻转环流（AMOC）是全球气候系统的重要组成部分。它负责大约四分之一的全球向北热量输送，并有助于欧洲温和的气候。观测和数值模式表明，AMOC的变化范围很广。最近的海洋环流模式（OGCM）在高分辨率配置（1/4 °）的结果表明，存在的超惯性变化的AMOC。在这项研究中，这一结果在理论框架的有效性进行了测试。在低Rossby数和存在的瑞利摩擦，它表明，不同于一个典型的强迫阻尼振荡器（显示亚惯性共振），AMOC经历超和亚惯性共振（除了在低纬度和高摩擦）。无量纲数Sr，测量年龄强迫与地转强迫的比率（即，纬向压力梯度与纬向压力梯度），表明这些共振中哪一种占主导地位。
AbstractThe Atlantic meridional overturning circulation (AMOC) is a crucial component of the global climate system. It is responsible for around a quarter of the global northward heat transport and contributes to the mild European climate. Observations and numerical models suggest a wide range of AMOC variability. Recent results from an ocean general circulation model (OGCM) in a high-resolution configuration (¼°) suggest the existence of superinertial variability of the AMOC. In this study, the validity of this result in a theoretical framework is tested. At a low Rossby number and in the presence of Rayleigh friction, it is demonstrated that, unlike a typical forced damped oscillator (which shows subinertial resonance), the AMOC undergoes both super- and subinertial resonances (except at low latitudes and for high friction). A dimensionless number Sr, measuring the ratio of ageo- to geostrophic forcing (i.e., the zonal versus meridional pressure gradients), indicates which of these resonances dominates....