Ezat, Mohamed M.Mohamed M.EzatRasmussen, Tine L.Tine L.RasmussenHain, Mathis P.Mathis P.HainGreaves, MervynMervynGreavesRae, James W. B.James W. B.RaeZamelczyk, KatarzynaKatarzynaZamelczykMarchitto, Thomas M.Thomas M.MarchittoSzidat, SönkeSönkeSzidat0000-0002-1824-6207Skinner, Luke C.Luke C.Skinner2024-09-022024-09-022021https://boris-portal.unibe.ch/handle/20.500.12422/42886The Fram Strait is the only deep gateway between the Arctic Ocean and the Nordic Seas and thus is a key area to study past changes in ocean circulation and the marine carbon cycle. Here, we study deep ocean temperature, δ18O, carbonate chemistry (i.e., carbonate ion concentration [CO3 2−]), and nutrient content in the Fram Strait during the late glacial (35,000–19,000 years BP) and the Holocene based on benthic foraminiferal geochemistry and carbon cycle modeling. Our results indicate a thickening of Atlantic water penetrating into the northern Nordic Seas, forming a subsurface Atlantic intermediate water layer reaching to at least ∼2,600 m water depth during most of the late glacial period. The recirculating Atlantic layer was characterized by relatively high [CO3 2−] and low δ13C during the late glacial, and provides evidence for a Nordic Seas source to the glacial North Atlantic intermediate water flowing at 2,000–3,000 m water depth, most likely via the Denmark Strait. In addition, we discuss evidence for enhanced terrestrial carbon input to the Nordic Seas at ∼23.5 ka. Comparing our δ13C and qualitative [CO3 2−] records with results of carbon cycle box modeling suggests that the total terrestrial CO2 release during this carbon input event was low, slow, or directly to the atmosphere.en500 - Science::540 - Chemistryarticle10.48350/15794310.1029/2021PA004216