Pliocene decoupling of equatorial Pacific temperature and pH gradients
Pliocene decoupling of equatorial Pacific temperature and pH gradients
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DOI：
10.1038/s41586-021-03884-7
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发表时间：
2021-10
期刊：
影响因子：
64.8
通讯作者：
M. Shankle;N. Burls;A. Fedorov;M. Thomas;Wei Liu;D. Penman;H. Ford;Peter H Jacobs;N. Planavsky-N.
中科院分区：
文献类型：
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作者：
M. Shankle;N. Burls;A. Fedorov;M. Thomas;Wei Liu;D. Penman;H. Ford;Peter H Jacobs;N. Planavsky-N.
赤道太平洋的海洋动力驱动着影响全世界海洋和陆地生态系统的热带气候模式。该地区如何应对全球变暖对全球气候、经济稳定和生态系统健康具有深远影响。因此，许多研究调查了上新世（530 - 260万年前）和中新世晚期（约600万年前）的赤道太平洋动力学，作为该地区在全球变暖下未来行为的模拟，-。从这个时候的古海洋学记录提出了一个明显的矛盾与代理证据减少东西海面温度梯度沿着赤道太平洋，-表明减少风驱动的上升与证据相冲突的增强生物生产力在东太平洋，-这通常是由于更强的上升流。在这里，我们调和这些意见，提供了一个完全不同的现代流通制度在上新世早期/中新世晚期，结果在更老，更酸性和更富营养的水到达赤道太平洋的新证据。这些结果提供了一个机制，提高生产力在上新世早期/中新世晚期东太平洋，即使在存在较弱的风驱动的上升流。我们的发现为赤道太平洋动力学提供了新的线索，并有助于限制它们在不久的将来将经历的潜在变化，因为预计地球将在下个世纪达到上新世的变暖水平。
Ocean dynamics in the equatorial Pacific drive tropical climate patterns that affect marine and terrestrial ecosystems worldwide. How this region will respond to global warming has profound implications for global climate, economic stability and ecosystem health. As a result, numerous studies have investigated equatorial Pacific dynamics during the Pliocene (5.3–2.6 million years ago) and late Miocene (around 6 million years ago) as an analogue for the future behaviour of the region under global warming, , , , , , , , , , –. Palaeoceanographic records from this time present an apparent paradox with proxy evidence of a reduced east–west sea surface temperature gradient along the equatorial Pacific,,,—indicative of reduced wind-driven upwelling—conflicting with evidence of enhanced biological productivity in the east Pacific, –that typically results from stronger upwelling. Here we reconcile these observations by providing new evidence for a radically different-from-modern circulation regime in the early Pliocene/late Miocene that results in older, more acidic and more nutrient-rich water reaching the equatorial Pacific. These results provide a mechanism for enhanced productivity in the early Pliocene/late Miocene east Pacific even in the presence of weaker wind-driven upwelling. Our findings shed new light on equatorial Pacific dynamics and help to constrain the potential changes they will undergo in the near future, given that the Earth is expected to reach Pliocene-like levels of warming in the next century.