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在洛伦蒂冰层脱冰过程中,冰流活动缩小到冰盖体积
C R Stokes1, M Margold1, C D Clark2
1Department of Geography, Durham University, Durham, UK.
Nature
|February 19, 2016
概括
古老的劳伦蒂冰层上的冰流数量随着时间的推移而减少. 这表明冰流对冰盖质量平衡的影响可能比以前认为的要小.
科学领域:
- 古气候学
- 冰川学
- 冰盖动力学
背景情况:
- 格陵兰和南极的冰盖在海平面上升方面发挥了重要作用,原因是冰川的稀疏和退缩.
- 预测未来海平面上升的不确定性源于冰流行为的有限长期数据.
- 了解冰流的演变对于准确的冰盖质量平衡预测至关重要.
研究的目的:
- 为了重建洛伦蒂冰层脱冰期间的冰流的历史活动.
- 调查冰河流网络如何在千年内演变.
- 评估冰流对冰盖质量平衡的长期影响
主要方法:
- 在洛伦蒂冰层脱冰过程中117个冰流活动的重建 (22,0007,000年前).
- 分析冰流的数量,空间范围,以及随着时间的推移而发生的排放.
- 冰流活动与底层地质,地形和冰盖体积变化的相关性.
主要成果:
- 随着洛伦蒂冰层的退缩,活跃冰流的数量减少.
- 随着时间的推移,冰流占据了冰盖周围的较小比例.
- 在整个脱冰期,冰流的排放总量都在下降.
结论:
- 根据冰盖体积的变化而调整的冰流活动和排水网络.
- 与一些理论相反,冰流在脱冰过程中对劳伦蒂冰层的质量平衡的影响越来越小.
- 尽管直接翻译需要谨慎,
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