由冰盖变化控制的突如其来的冰川气候变化.
Xu Zhang1, Gerrit Lohmann2, Gregor Knorr3
1Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bussestrasse 24, D-27570 Bremerhaven, Germany.
Nature
|August 15, 2014
概括
北半球冰盖 (NHIS) 的逐渐变化可以引发快速的冰川气候变化,如Dansgaard-Oeschger (DO) 事件. 这种机制解释了千年规模的气候变化和冰河时代的突然变化.
科学领域:
- 古气候学 古气候学
- 气候建模 气候建模
- 四年纪地质学四年纪地质学
背景情况:
- 千年规模的变暖事件,称为Dansgaard-Oeschger (DO) 事件,是晚期普莱斯托纪冰川时期的突出特征.
- 代理数据揭示了冰川期间的反复,快速的气候变化,可以追溯到80万年前,促使对其原因进行了广泛的研究.
研究的目的:
- 通过使用综合气候模型,研究产生Dansgaard-Oeschger (DO) 事件的连贯机制.
- 探索北半球冰盖 (NHIS) 高度在引发冰川气候突然变化的作用.
主要方法:
- 使用了一个全面的完全合的大气-海洋-海冰模型.
- 模拟北半球冰盖 (NHIS) 高度的逐渐变化.
- 分析了模拟的全球气候反应,包括北大西洋温度,热带雨带转移和南半球冷却.
主要成果:
- 逐渐的NHIS高度变化可以诱导类似于DO事件的快速冰川气候变化.
- 模拟反应,如北大西洋变暖和双极波动,与经验证据一致.
- 确定了一种涉及两个冰川海洋循环状态和北大西洋正反循环的机制.
结论:
- 北半球冰盖 (NHIS) 的体积变化为DO事件和千年级气候变化提供了一个连贯的机制.
- 急剧的气候转型是由NHIS高度和CO2水平的微小变化引发的,由海洋循环状态促进.
- 这项研究将冰川千年规模的变化和突然的气候变化与中间冰盖动态联系起来.
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