Atlantic and Pacific tropics connected by mutually interactive decadal-timescale processes
Atlantic and Pacific tropics connected by mutually interactive decadal-timescale processes
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DOI：
10.1038/s41561-020-00669-x
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发表时间：
2020-12-14
影响因子：
18.3
通讯作者：
Rosenbloom, Nan
中科院分区：
文献类型：
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作者：
Meehl, Gerald A.;Hu, Aixue;Rosenbloom, Nan
十年期气候预测假设存在十年期时间尺度的过程和机制，如果在模型中正确初始化，可能提供未来一年或两年以上的预测技能。候选机制包括太平洋年代际变率和大西洋年代际变率，其要素涉及热带太平洋和大西洋海表温度（SST）从正异常（正相位）到负异常（负相位）的缓慢波动。在这里，我们使用模型实验表明，往往是一个弱的相反的迹象SST响应在热带太平洋时，观察到的SST指定在大西洋，而有一个弱的同号SST响应在热带大西洋时，观察到的SST指定在热带太平洋。大西洋的净表面热通量和太平洋的海洋动力学在海洋对各自流域特定SST的响应中起着截然不同的作用。我们建议，在太平洋和大西洋的过程是通过大气步行者环流沿着与中纬度遥相关的贡献，大西洋对太平洋的响应顺序互动。
Decadal climate prediction presumes there are decadal-timescale processes and mechanisms that, if initialized properly in models, potentially provide predictive skill more than one or two years into the future. Candidate mechanisms involve Pacific decadal variability and Atlantic multidecadal variability, elements of which involve slow fluctuations of tropical Pacific and Atlantic sea surface temperatures (SSTs) from positive anomalies (positive phase) to negative anomalies (negative phase). Here we use model experiments to show that there tends to be a weak opposite-sign SST response in the tropical Pacific when observed SSTs are specified in the Atlantic, while there is a weak same-sign SST response in the tropical Atlantic when observed SSTs are specified in the tropical Pacific. Net surface heat flux in the Atlantic and ocean dynamics in the Pacific play contrasting roles in the ocean response to specified SSTs in the respective basins. We propose that processes in the Pacific and Atlantic are sequentially interactive through the atmospheric Walker circulation along with contributions from midlatitude teleconnections for the Atlantic response to the Pacific.