North Atlantic Water Mass Distribution since the Last Glacial Maximum: New Insights

摘要: A prominent feature of the glacial North Atlantic was the presence of large hydrographic gradients in mid-depth-to deep-water properties, suggesting that the Atlantic Meridional Overturning circulation was fundamentally different from today. The different states in convection are related to a switch from mainly shallow overturning (glacial mode) to deep overturning in the North Atlantic (modern mode). However, sedimentary proxy data from shallow core sites of the North Atlantic is very sparse (white dots, Figure 1), impedes drawing a full picture of the glacial North Atlantic circulation regime. Here we present epibenthic stable carbon isotope records (13C) from a depth transect of high-resolution sediment cores off Newfoundland in the subpolar Northwest Atlantic. In particular, our new proxy records cover a wide range of water depths ranging between~ 1100 and 4000 m water depth (yellow stars, Figure 1), allowing us …