东南极冰盖的广泛持续加厚是由于从底部开始结而导致的
Robin E Bell1, Fausto Ferraccioli, Timothy T Creyts
1Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA. robinb@ldeo.columbia.edu
概括
在东南极洲下面发生广泛的结.
科学领域:
- 冰川学的冰川学
- 地质物理学 地质物理学
- 气候科学 气候科学
背景情况:
- 冰盖的增长主要是由表面积积雪所驱动的.
- 亚冰川过程可以显著影响冰盖动态.
- 了解基底冰的形成对于准确的冰盖建模至关重要.
研究的目的:
- 调查东南极洲基本结的程度和影响.
- 分析驱动亚冰川冰形成的机制.
- 评估结如何影响冰盖质量平衡和动态.
主要方法:
- 在国际北极年期间进行空气地质物理调查.
- 冰盖基层组成和厚度的分析.
- 模拟亚冰川水的行为和冰的形成.
主要成果:
- 在A圆顶下方的冰盖基面积的24%有结的证据.
- 在某些地区,基底结占冰厚的50%左右.
- 冰是山脊和山谷墙壁附近的亚冰川水的冷却和超级冷却造成的.
结论:
- 基本结是一个重要的过程,推动了东南极洲的大规模重新分配.
- 结会改变冰的风湿学,扭曲冰盖,并影响气候档案.
- 目前的冰盖模型可能无法完全捕捉基底结对冰流的影响.
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