限制南极冰盖对最后一个冰河间海平面的贡献
Robert L Barnett1,2, Jacqueline Austermann3, Blake Dyer4
1Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK.
Science advances
|July 5, 2023
概括
在最后的冰河间时期,更高的极地温度影响了冰盖. 南极冰的融化较早达到顶峰,随后格陵兰冰盖的质量损失较晚,显示出异步的冰盖行为.
科学领域:
- 古气候学 古气候学
- 冰川学的冰川学
- 海平面研究的研究.
背景情况:
- 最后的冰河间 (LIG) 时期 (~129-116 ka) 经历了比现在更温暖的极地温度.
- 了解LIG期间冰盖对变暖的反应对于未来气候预测至关重要.
- 关于LIG期间南极和格陵兰冰盖变化的时间和规模存在重大辩论.
研究的目的:
- 重建LIG期间南极和格陵兰冰盖在海平面上的贡献.
- 为了确定这些主要冰盖冰融的时间.
- 为了研究过去的间冰期期间冰盖质量损失的异步与同步性质.
主要方法:
- 来自英国,法国和丹麦的最后一个冰河间海平面观测的汇编和绝对约会.
- 使用冰川静态调整 (GIA) 模型来区分区域海平面变化.
- 通过尽量减少格陵兰岛冰盖的影响,限制南极冰盖的融化贡献.
主要成果:
- 南极冰盖对全球平均海平面的贡献在LIG早期 (在126 ka之前) 达到顶峰.
- 南极的最大贡献达到估计的5.7米 (有68%的概率范围为3.68.7米).
- 格陵兰冰盖的质量损失发生在LIG的后期,支持异步融化历史.
结论:
- 南极冰川融化是早期LIG海平面上升的主要驱动因素.
- 格陵兰冰盖在LIG的后期导致海平面上升.
- 在LIG期间的冰盖融化是异步的,南极和格陵兰的贡献时间不同.
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