Pliocene decoupling of equatorial Pacific temperature and pH gradients

Pliocene decoupling of equatorial Pacific temperature and pH gradients

Ocean dynamics durante the equatorial Pacific drive tropical climate patterns that affect marine and terrestrial ecosystems worldwide. How this region will respond sicuro 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 spillo) and late Miocene (around 6 million years spillo) as an analogue for the future behaviour of the region under global warming 1,2,3,4,5,6,7,8,9,10,11,12 . Palaeoceanographic records from this time present an apparent paradox with proxy evidence of per reduced east–west sea surface temperature gradient along the equatorial Pacific 1,3,7,8 -indicative of reduced wind-driven upwelling-conflicting with evidence of enhanced biological productivity durante the east Pacific 13,14,15 that typically results from tagliandi biker planet stronger upwelling. Here we reconcile these observations by providing new evidence for per radically different-from-modern circulation governo per the early Pliocene/late Miocene 16 that results mediante older, more acidic and more nutrient-rich water reaching the equatorial Pacific. These results provide a mechanism for enhanced productivity durante the early Pliocene/late Miocene east Pacific even mediante the presence of weaker wind-driven upwelling. Our findings shed new light on equatorial Pacific dynamics and help onesto constrain the potential changes they will undergo durante the near future, given that the Earth is expected to reach Pliocene-like levels of warming con the next century.

Datazione availability

The proxy giorno and model output produced mediante this study are available as .xlsm files per NOAA’s paleoclimate momento repository ( ( Source tempo are provided with this paper.

Code availability

The code used mediante this paper esatto produce pH from d 11 B (and to produce all the proxy-related figures) is publicly available as Matlab scripts on GitHub ( The CESM code is available from The Python code used to create select model figures is available at Source datazione are provided with this paper.


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