Nature. 2006 Nov 9;444(7116):195-8. doi: 10.1038/nature05301.
Precise knowledge of the phase relationship between climate changes in the two hemispheres is a key for understanding the Earth's climate dynamics. For the last glacial period, ice core studies have revealed strong coupling of the largest millennial-scale warm events in Antarctica with the longest Dansgaard-Oeschger events in Greenland through the Atlantic meridional overturning circulation. It has been unclear, however, whether the shorter Dansgaard-Oeschger events have counterparts in the shorter and less prominent Antarctic temperature variations, and whether these events are linked by the same mechanism. Here we present a glacial climate record derived from an ice core from Dronning Maud Land, Antarctica, which represents South Atlantic climate at a resolution comparable with the Greenland ice core records. After methane synchronization with an ice core from North Greenland, the oxygen isotope record from the Dronning Maud Land ice core shows a one-to-one coupling between all Antarctic warm events and Greenland Dansgaard-Oeschger events by the bipolar seesaw6. The amplitude of the Antarctic warm events is found to be linearly dependent on the duration of the concurrent stadial in the North, suggesting that they all result from a similar reduction in the meridional overturning circulation.
精确了解两个半球气候变化之间的相位关系是理解地球气候动力学的关键。对于上一个冰期，冰芯研究表明，通过大西洋经向翻转环流，南极洲最大的千年尺度暖事件与格陵兰最长的丹斯加德-奥施格事件之间存在强烈耦合。然而，尚不清楚较短的丹斯加德-奥施格事件在较短且不太显著的南极温度变化中是否有对应事件，以及这些事件是否通过相同机制相联系。在此，我们展示了一份来自南极洲毛德皇后地冰芯的冰川气候记录，它代表了南大西洋气候，分辨率与格陵兰冰芯记录相当。在将甲烷与北格陵兰的一个冰芯同步后，毛德皇后地冰芯的氧同位素记录显示，所有南极暖事件与格陵兰丹斯加德-奥施格事件之间通过双极跷跷板效应呈现一一对应关系。发现南极暖事件的幅度与北半球同期冰期的持续时间呈线性相关，这表明它们都是由经向翻转环流的类似减弱导致的。
