Department of Geography, University of Cambridge, Cambridge, CB2 3EN, UK.
Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, 10964, USA.
Nat Commun. 2019 Mar 20;10(1):1272. doi: 10.1038/s41467-019-09237-3.
Constraining the response time of the climate system to changes in North Atlantic Deep Water (NADW) formation is fundamental to improving climate and Atlantic Meridional Overturning Circulation predictability. Here we report a new synchronization of terrestrial, marine, and ice-core records, which allows the first quantitative determination of the response time of North Atlantic climate to changes in high-latitude NADW formation rate during the last deglaciation. Using a continuous record of deep water ventilation from the Nordic Seas, we identify a ∼400-year lead of changes in high-latitude NADW formation ahead of abrupt climate changes recorded in Greenland ice cores at the onset and end of the Younger Dryas stadial, which likely occurred in response to gradual changes in temperature- and wind-driven freshwater transport. We suggest that variations in Nordic Seas deep-water circulation are precursors to abrupt climate changes and that future model studies should address this phasing.
约束气候系统对北大西洋深层水（NADW）形成变化的响应时间对于提高气候和大西洋经向翻转环流的可预测性至关重要。在这里，我们报告了一个新的陆地、海洋和冰芯记录的同步，这使得首次能够定量确定北大西洋气候对末次冰消期高纬度 NADW 形成率变化的响应时间。利用来自北欧海的深部通风的连续记录，我们确定了在格陵兰冰芯记录的年轻冰期开始和结束时记录的突发性气候变化之前，高纬度 NADW 形成的变化大约提前了 400 年，这可能是由于温度和风驱动的淡水输送的逐渐变化而发生的。我们认为，北欧海深层水环流的变化是突发性气候变化的前兆，未来的模型研究应该解决这个问题。
