格陵兰西北部在海洋同位素第11阶段的脱冰
Andrew J Christ1,2, Tammy M Rittenour3, Paul R Bierman1,2
1Rubenstein School of the Environment and Natural Resources, University of Vermont, Burlington, VT 05405, USA.
概括
在过去的冰河间期,格陵兰西北地区是没有冰的,海上同位素阶段11. 这一发现表明格陵兰冰盖对海平面上升有很大影响.
科学领域:
- 古气候学
- 冰川学
- 地质时间学
背景情况:
- 过去的冰河间时期为未来气候变化对冰盖和海平面上升的影响提供了关键的类比.
- 没有冰的地区的地质记录对于了解过去的冰盖行为至关重要, 但很少.
研究的目的:
- 调查格陵兰西北部在过去的间冰期的无冰状态.
- 使用冰下沉积物重建无冰期的时间和环境条件.
- 估计格陵兰冰盖在间冰期对海平面上升的潜在贡献.
主要方法:
- 潜冰层沉积物的发光年龄,以确定沉积年龄.
- 来源分析以确定沉积物来源.
- 测定宇宙原核的年龄,以评估沉积物暴露史.
- 模拟无冰条件和海平面贡献的冰盖建模.
主要成果:
- 来自Camp Century冰芯的冰下沉积物提供了海上同位素阶段11期间格陵兰西北部无冰的直接证据.
- 发光日期表明沉积物在416±38000年前被流水所沉积.
- 在沉积之前的16000年内发生了沉积物再处理和表面暴露.
- 冰盖模型表明,一个没有冰的世纪营需要至少1.4米的海平面相当于格陵兰冰盖的贡献.
结论:
- 格陵兰西北部在海洋同位素阶段11期期间是没有冰的.
- 格陵兰冰层在过去的间冰期中经历了大量的冰损失.
- 这些发现凸显了格陵兰在气候变暖的条件下海平面上升的潜力.
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