在过去的750万年里,东格陵兰冰层持续存在
Paul R Bierman1, Jeremy D Shakun2, Lee B Corbett1
1Department of Geology and Rubenstein School of the Environment and Natural Resources, University of Vermont, Burlington, Vermont 05405, USA.
Nature
|December 9, 2016
概括
东格陵兰冰层已经持续了数百万年,在普世早期出现了动态变化,后来出现了广泛的冰层. 这挑战了过去温暖时期完全脱冰的观念.
科学领域:
- 古气候学
- 冰川学
- 海洋地质化学
背景情况:
- 了解过去的冰盖行为对于预测未来海平面上升至关重要.
- 地球上古代冰盖的记录往往被侵蚀,年龄也很差.
- 海洋沉积物提供了更连续的冰盖变化记录.
研究的目的:
- 在过去的750万年里重建东格陵兰冰盖的历史.
- 在关键气候转变期间调查冰盖动态.
- 挑战过去的冰河间完全消融的假设.
主要方法:
- 在海洋沉积物中分析和同位素 (10Be和26Al).
- 使用宇宙核化物追踪冰川侵蚀和沉积物运输.
- 解释同位素特征以推断冰盖的范围和活动.
主要成果:
- 东格陵兰冰盖已经持续存在至少750万年.
- 冰层在普莱斯托纪早期是动态的,在普莱斯托纪中后期是广泛的.
- 同位素数据与主要的气候转变相关,表明冰盖的行为发生了变化.
结论:
- 这项研究提供了数百万年来东格陵兰完全和扩展脱冰的证据.
- 过去的冰盖行为是复杂而多样化的,特别是在气候变化期间.
- 未来的沉积率较高的地点研究可以更好地了解冰川间的冰盖动态.
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