Effects of the 18.6-yr Modulation of Tidal Mixing on the North Pacific Bidecadal Climate Variability in a Coupled Climate Model
Effects of the 18.6-yr Modulation of Tidal Mixing on the North Pacific Bidecadal Climate Variability in a Coupled Climate Model
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耦合气候模型中18.6年潮汐混合调制对北太平洋年代际气候变率的影响
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发表时间：
2012
期刊：
影响因子：
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通讯作者：
S. Osafune
中科院分区：
文献类型：
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作者：
Yuki Tanaka;I. Yasuda;H. Hasumi;H. Tatebe;S. Osafune
由潮汐-地形相互作用引起的贯向混合是维持全球海洋环流和全球气候的重要因素之一，它受月球轨道倾角18.6年周期振荡的调制，因此被认为影响了双十年气候变率。在这项研究中，空间分布的diapycnal扩散连同其18.6年的振荡估计从全球潮汐模式被纳入一个国家的最先进的数值耦合气候模式，研究其对北太平洋气候变率的影响，并了解潜在的物理机制。结果表明，黑潮-俄亥俄延伸区存在显著的海表温度（SST）异常，其周期为18.6年，强（弱）潮混合时，SST往往出现正（负）异常。这首先是由千岛海峡附近的异常水平环流引起的，那里的潮汐调制增强。
AbstractDiapycnal mixing induced by tide–topography interaction, one of the essential factors maintaining the global ocean circulation and hence the global climate, is modulated by the 18.6-yr period oscillation of the lunar orbital inclination, and has therefore been hypothesized to influence bidecadal climate variability. In this study, the spatial distribution of diapycnal diffusivity together with its 18.6-yr oscillation estimated from a global tide model is incorporated into a state-of-the-art numerical coupled climate model to investigate its effects on climate variability over the North Pacific and to understand the underlying physical mechanism. It is shown that a significant sea surface temperature (SST) anomaly with a period of 18.6 years appears in the Kuroshio–Oyashio Extension region; a positive (negative) SST anomaly tends to occur during strong (weak) tidal mixing. This is first induced by anomalous horizontal circulation localized around the Kuril Straits, where enhanced modulation of tida...