Weaker Nordic Seas convection and bottom water warming during Greenland stadials

Weaker Nordic Seas convection and bottom water warming during Greenland stadials | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Weaker Nordic Seas convection and bottom water warming during Greenland stadials Christine Lockwood-Ireland, Tine Rasmussen, Mohamed Ezat, James Rae, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6687057/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Deep water formation maintains stronger bottom currents in the modern Nordic Seas, supplying overflow waters which feed the Atlantic Meridional Overturning Circulation (AMOC). Past glacial millennial-scale abrupt cold-warm climate transitions, called Dansgaard-Oeschger (D-O) events, and their driving mechanisms remain poorly understood. Here, we combine the palaeo-flow bottom-current strength proxy (´sortable silt´) with geochemical (benthic foraminiferal Mg/Ca and δ 18 O) analyses from an archive from the central eastern Nordic Seas. During most cold D-O and Heinrich stadials, intermediate waters warmed and bottom currents were weak, suggesting that the inflowing Atlantic water had thickened, and convection was suppressed. Warm interstadials had opposite conditions, with stronger bottom currents and cold intermediate waters. Bottom currents weakened during the long interstadial transitional cooling phases. Prior to the stadial onsets, bottom currents and advection of warm Atlantic surface water were revived, likely triggering cryosphere and salinity changes that resulted in stadial climate. Earth and environmental sciences/Climate sciences/Palaeoceanography Earth and environmental sciences/Climate sciences/Palaeoclimate Earth and environmental sciences/Climate sciences/Cryospheric science Earth and environmental sciences/Ocean sciences/Marine chemistry Earth and environmental sciences/Climate sciences/Climate change/Projection and prediction Full Text Additional Declarations There is NO Competing Interest. Supplementary Files LockwoodIrelandetalSupplementaryDataset1.xlsx Dataset 1 LockwoodIrelandetal.SupplementaryInformation.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6687057","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":458581267,"identity":"1be0a171-06ac-49fb-8b30-4de304683db6","order_by":0,"name":"Christine 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Past glacial millennial-scale abrupt cold-warm climate transitions, called Dansgaard-Oeschger (D-O) events, and their driving mechanisms remain poorly understood. Here, we combine the palaeo-flow bottom-current strength proxy (\u0026acute;sortable silt\u0026acute;) with geochemical (benthic foraminiferal Mg/Ca and δ\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003eO) analyses from an archive from the central eastern Nordic Seas. During most cold D-O and Heinrich stadials, intermediate waters warmed and bottom currents were weak, suggesting that the inflowing Atlantic water had thickened, and convection was suppressed. Warm interstadials had opposite conditions, with stronger bottom currents and cold intermediate waters. Bottom currents weakened during the long interstadial transitional cooling phases. 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