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dc.contributor.authorWorne, S
dc.contributor.authorKender, S
dc.contributor.authorSwann, GEA
dc.contributor.authorLeng, MJ
dc.contributor.authorRavelo, AC
dc.date.accessioned2020-06-17T10:26:48Z
dc.date.issued2020-06-08
dc.description.abstractReduction in atmosphericpCO2has been hypothesised as a causal mechanism for the Mid-Pleistocene Transition(MPT), which saw global cooling and increased duration of glacials between 0.6 and 1.2 Ma. Sea ice-modulatedhigh latitude upwelling and ocean-atmospheric CO2flux is considered a potential mechanism forpCO2decline,although there are no long-term nutrient upwelling records from high latitude regions to test this hypothesis.Using nitrogen isotopes and opal mass accumulation rates from 0 to 1.2 Ma, we calculate a continuous highresolution nutrient upwelling index for the Bering Sea and assess possible changes to regional CO2fluxes and tothe relative control of sea ice, sea level and glacial North Pacific Intermediate Water (GNPIW) on deep mixingand nutrient upwelling in the region. Wefind nutrient upwelling in the Bering Sea correlates with global icevolume and air temperature throughout the study interval. From ~1 Ma, and particularly during the 900 kaevent, suppressed nutrient upwelling would have lowered oceanicfluxes of CO2to the atmosphere supporting areduction in globalpCO2during the MPT. This timing is consistent with a pronounced increase in sea ice duringthe early Pleistocene and restriction offlow through the Bering Strait during glacials after ~900 ka, both ofwhich would have acted to suppress upwelling. We suggest that sea-level modulated GNPIW expansion duringglacials after 900 ka was the dominant control on subarctic Pacific upwelling strength during the mid-latePleistocene, while sea ice variability played a secondary role.en_GB
dc.description.sponsorshipNatural Environment Research Council (NERC)en_GB
dc.identifier.citationVol. 555: 109845en_GB
dc.identifier.doi10.1016/j.palaeo.2020.109845
dc.identifier.grantnumberIP-1674-1116en_GB
dc.identifier.urihttp://hdl.handle.net/10871/121491
dc.language.isoenen_GB
dc.publisherElsevieren_GB
dc.rights.embargoreasonUnder embargo until 8 June 2021 in compliance with publisher policy.en_GB
dc.rights© 2020. This version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/  en_GB
dc.subjectMPTen_GB
dc.subjectSea Iceen_GB
dc.subjectCO2en_GB
dc.subjectBering Seaen_GB
dc.subjectUpwelling indexen_GB
dc.titleReduced upwelling of nutrient and carbon-rich water in the subarctic Pacific during the Mid-Pleistocene Transitionen_GB
dc.typeArticleen_GB
dc.date.available2020-06-17T10:26:48Z
dc.identifier.issn0031-0182
exeter.article-number109845en_GB
dc.descriptionThis is the author accepted manuscript. The final version is available from the publisher via the DOI in this recorden_GB
dc.identifier.journalPalaeogeography, Palaeoclimatology, Palaeoecologyen_GB
dc.rights.urihttps://creativecommons.org/licenses/by-nc-nd/4.0/  en_GB
dcterms.dateAccepted2020-06-03
rioxxterms.versionAMen_GB
rioxxterms.licenseref.startdate2020-06-03
rioxxterms.typeJournal Article/Reviewen_GB
refterms.dateFCD2020-06-17T10:22:53Z
refterms.versionFCDAM
refterms.panelBen_GB


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© 2020. This version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/  
Except where otherwise noted, this item's licence is described as © 2020. This version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/