Rigalleau Vincent, Lamy Frank, Ruggieri Nicoletta, Sadatzki Henrik, Arz Helge W, Barker Stephen, Lembke-Jene Lester, Wegwerth Antje, Knorr Gregor, Venancio Igor M, Pinho Tainã M L, Tiedemann Ralf, Winckler Gisela
Alfred-Wegener-Institute, Helmholtz Center for Polar and Marine Research, Bremerhaven, Germany.
MARUM-Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany.
Nat Commun. 2025 Apr 1;16(1):3105. doi: 10.1038/s41467-025-58458-2.
Millennial-scale variations in the strength and position of the Antarctic Circumpolar Current exert considerable influence on the global meridional overturning circulation and the ocean carbon cycle. The mechanistic understanding of these variations is still incomplete, partly due to the scarcity of sediment records covering multiple glacial-interglacial cycles with millennial-scale resolution. Here, we present high-resolution current strength and sea surface temperature records covering the past 790,000 years from the Cape Horn Current as part of the subantarctic Antarctic Circumpolar Current system, flowing along the Chilean margin. Both temperature and current velocity data document persistent millennial-scale climate variability throughout the last eight glacial periods with stronger current flow and warmer sea surface temperatures coinciding with Antarctic warm intervals. These Southern Hemisphere changes are linked to North Atlantic millennial-scale climate fluctuations, plausibly involving changes in the Atlantic thermohaline circulation. The variations in the Antarctic Circumpolar Current system are associated with atmospheric CO changes, suggesting a mechanistic link through the Southern Ocean carbon cycle.
南极绕极流强度和位置的千年尺度变化对全球经向翻转环流和海洋碳循环产生了相当大的影响。对这些变化的机制理解仍不完整，部分原因是缺乏具有千年尺度分辨率的、覆盖多个冰期-间冰期循环的沉积物记录。在这里，我们展示了来自合恩角海流的过去79万年的高分辨率海流强度和海面温度记录，合恩角海流是亚南极南极绕极流系统的一部分，沿着智利边缘流动。温度和流速数据都记录了在过去八个冰期期间持续存在的千年尺度气候变化，海流更强、海面温度更高的时期与南极暖期相吻合。这些南半球的变化与北大西洋千年尺度的气候波动有关，可能涉及大西洋热盐环流的变化。南极绕极流系统的变化与大气二氧化碳变化有关，这表明通过南大洋碳循环存在一种机制联系。
