降冰导致海平面迅速上升的原因是冰盖的塌
Lauren J Gregoire1, Antony J Payne, Paul J Valdes
1School of Geographical Sciences, University of Bristol, University Road, Bristol BS8 1SS, UK. lauren.gregoire@bristol.ac.uk
Nature
|July 13, 2012
概括
在最后一次脱冰过程中,冰盖的崩导致了急剧的融水脉冲,导致海平面迅速上升. 这种机制解释了像融水脉冲1A和8200年事件这样的重大事件.
科学领域:
- 古气候学 古气候学
- 冰川学的冰川学
- 气候建模 气候建模
背景情况:
- 最后一次降冰的特点是融水突发的脉冲导致气候变化.
- 大约14000年前的融水脉冲1A (MWP-1A) 在350年内导致海平面上升14-18米.
- 关于MWP-1A和类似事件的来源和机制仍在争论中.
研究的目的:
- 为了研究主要融水脉冲背后的冰盖动态.
- 确定MWP-1A的地理来源和物理机制.
- 为了探索冰塌和突发气候事件之间的潜在联系.
主要方法:
- 进行了冰盖建模模拟.
- 该模型模拟了北美冰盖 (劳伦蒂和科德里勒山) 的分离.
- 该模型调查了冰圆顶分离和表面降低在融水释放中的作用.
主要成果:
- 模拟的冰盖分离,特别是劳伦蒂和科尔迪勒山,产生了与MWP-1A一致的脉冲.
- 拉布拉多和巴芬冰顶的分离模拟了与8200年事件相关的脉冲.
- 由于变暖和表面降低而导致冰的崩加速了融化,在模拟事件中导致500年内海平面上升约9米.
结论:
- 冰"马崩"被提出为MWP-1A和8200年事件的机制.
- 这种机制突显了冰盖动态对过去海平面和气候的重大影响.
- 了解这些事件可以了解冰盖的行为和气候反应.
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