College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA.
Australian National University, Canberra ACT.
Science. 2020 Nov 6;370(6517):716-720. doi: 10.1126/science.aba7096. Epub 2020 Oct 1.
New radiocarbon and sedimentological results from the Gulf of Alaska document recurrent millennial-scale episodes of reorganized Pacific Ocean ventilation synchronous with rapid Cordilleran Ice Sheet discharge, indicating close coupling of ice-ocean dynamics spanning the past 42,000 years. Ventilation of the intermediate-depth North Pacific tracks strength of the Asian monsoon, supporting a role for moisture and heat transport from low latitudes in North Pacific paleoclimate. Changes in carbon-14 age of intermediate waters are in phase with peaks in Cordilleran ice-rafted debris delivery, and both consistently precede ice discharge events from the Laurentide Ice Sheet, known as Heinrich events. This timing precludes an Atlantic trigger for Cordilleran Ice Sheet retreat and instead implicates the Pacific as an early part of a cascade of dynamic climate events with global impact.
来自阿拉斯加湾的新放射性碳和沉积学研究结果表明，太平洋通风在过去 42000 年里与快速的科迪勒拉冰盖排放同步发生了反复的千年规模事件，表明冰海动力学的紧密耦合。北太平洋中层水的通风与亚洲季风的强度有关，支持了低纬度地区的水分和热量向北太平洋古气候输送的作用。中间水的碳-14 年龄变化与科迪勒拉冰漂碎屑输送的峰值同步，且均先于被称为 Heinrich 事件的拉伦蒂德冰盖的冰排放事件。这种时间关系排除了北大西洋触发科迪勒拉冰盖退缩的可能性，而是暗示了太平洋作为一系列具有全球影响的动态气候事件的早期部分。
