Pacific Decadal Oscillation-like variability at a millennial timescale during the Holocene
Pacific Decadal Oscillation-like variability at a millennial timescale during the Holocene
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全新世千年时间尺度上的太平洋年代际振荡类变化
DOI：
10.1016/j.gloplacha.2021.103448
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发表时间：
2021
影响因子：
3.9
通讯作者：
Xiaojian Zhang
中科院分区：
文献类型：
--
作者：
Chunzhu Chen;Wenwei Zhao;Xiaojian Zhang
北太平洋海表温度对全球气候和生态系统变化有重要影响。太平洋年代际振荡（PDO）是北太平洋海温年代际变化的主导模态。在全新世的千年时间尺度的PDO样的变化仍然知之甚少。在这项研究中，千年尺度PDO样的变化在全新世进行了探讨，使用模型数据比较。为了减少不同年龄控制所带来的不确定性，本研究使用两种类型的代理记录重建了全新世PDO类指数，包括1）北太平洋外的东西SST对比和2）PDO相关的东亚降水异常。这两个重建结果揭示了全新世PDO型的一致变化，在10.4- 8.5kaBP和3.5- 3.0kaBP出现了正相，在8.5- 3.5kaBP和3.0- 0.2kaBP出现了负相。气候模拟表明，千年尺度的PDO的变化主要是由轨道强迫在全新世，导致一个积极的阶段的PDO的政权在全新世早期。在3.5 ~ 3.0kaBP之间的PDO机制的正相可能是由气候系统的内部反馈引起的，而气候模拟未能捕捉到这一点。
Sea surface temperatures (SSTs) in the North Pacific exert a great influence on global climate and ecosystem changes. The Pacific Decadal Oscillation (PDO) is the leading mode of decadal SST variability in the North Pacific. The PDO-like variability at a millennial timescale during the Holocene is still poorly understood. In this study, the millennial-scale PDO-like variability during the Holocene is explored using model–data comparisons. To reduce the uncertainties caused by differential age controls, this study reconstructs the Holocene PDO-like index using two types of published proxy records, including 1) east–west SST contrast in the extratropical North Pacific and 2) PDO-related precipitation anomalies in East Asia. These two reconstructions reveal coherent changes in the PDO-like pattern during the Holocene, showing positive phases at 10.4–8.5 ka BP and 3.5–3.0 ka BP, and negative phases at 8.5–3.5 ka BP and 3.0–0.2 ka BP. Climate simulations suggest that the millennial-scale PDO-like variability is predominantly controlled by orbital forcing during the Holocene, leading to a positive phase of the PDO-like regime during the early Holocene. The positive phase of the PDO-like regime between 3.5 and 3.0 ka BP was probably caused by the internal feedback of the climate system, which the climate simulations fail to capture.