Paleobathymetric reconstructions of the SW Barents Seaway and their implications for Atlantic–Arctic ocean circulation

Abstract

Abstract Unravelling past, large-scale ocean circulation patterns is crucial for deciphering the long-term global paleoclimate. Here we apply numerical modelling to reconstruct the detailed paleobathymetry-topography of the southwestern inlet of the Barents Seaway that presently connects the Atlantic and Arctic oceans. Subaerial topography was likely enough to block Atlantic Water from entering the Barents Seaway in the earliest Eocene (c. 55 Ma). The water may have entered in the middle Eocene (c. 47 Ma) as observed from major basin subsidence, but paleotopographic highs to the east may have hindered connections between the two oceans. From the Oligocene (c. 33 Ma) until the onset of the Quaternary (c. 2.7 Ma), basin shallowing and regional shelf uplift blocked Atlantic Water from entering the Barents Seaway. Our results imply that the Fram Strait remained the sole gateway for Atlantic Water into the Arctic Ocean since its opening in the Miocene until the Quaternary.