Ocean dynamics sopra the equatorial Pacific drive tropical climate patterns that affect marine and terrestrial ecosystems worldwide. How this region will respond onesto 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 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 verso 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 con the east Pacific 13,14,15 that typically results from stronger upwelling. Here we reconcile these observations by providing new evidence for a radically different-from-modern circulation consuetudine sopra the early Pliocene/late Miocene 16 that results con older, more acidic and more nutrient-rich water reaching the equatorial Pacific. These results provide a mechanism for enhanced productivity con 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 preciso constrain the potential changes they will undergo sopra the near future, given that the Earth is expected onesto reach Pliocene-like levels of warming per the next century.
Scadenza availability
The proxy momento and model output produced per this study are available as .xlsm files sopra NOAA’s paleoclimate data repository ( ( Source scadenza are provided with this paper.
Code availability
The code used per this paper esatto produce pH from d 11 B (and puro produce all the proxy-related figures) is publicly available as Matlab scripts on GitHub ( The CESM 1.2.2.1 code is available from The Python code used onesto create select model figures is available at Source giorno are provided with this paper.
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