南极冰盖的损失是由冰架的基底融化驱动的
H D Pritchard1, S R M Ligtenberg, H A Fricker
1British Antarctic Survey, Natural Environment Research Council, Madingley Road, Cambridge CB3 0ET, UK. h.pritchard@bas.ac.uk
Nature
|April 28, 2012
概括
南极冰架由于基底融化的增加而变薄,主要是由不断变化的风驱动的. 这种稀释减少了冰架的支,加速了冰川的流动,并导致全球海平面上升.
科学领域:
- 冰川学的冰川学
- 气候科学 气候科学
- 海洋学 海洋学 海洋学
背景情况:
- 南极冰盖边缘的冰川加速正在加剧.
- 冰架薄化和崩塌可以减少支,导致冰川流量增加.
- 了解冰架薄化的原因和影响对于预测海平面上升至关重要.
研究的目的:
- 为了调查南极冰架变薄的模式和原因.
- 为了确定冰架薄化,基底融化和冰川加速之间的联系.
- 评估气候强迫对南极冰盖质量平衡和海平面的影响.
主要方法:
- 卫星激光测高仪用于测量冰架厚度变化.
- 模拟表面的第一层.
- 海洋学和大气强迫的分析.
主要成果:
- 鉴定了一种围绕南极的冰架薄化模式,其原因是基底融化的增加.
- 推断出基底融化是南极冰盖通过减少支损失的主要驱动因素.
- 观察到的稀释率最高的地方是温暖的深水通过潜水槽进入冰架.
- 连接的风力迫使基底融化和冰架崩通过海洋上升和大气变暖.
结论:
- 气候强迫,特别是风力变化,显著影响南极冰盖质量平衡.
- 由于基底融化的冰架稀薄是控制南极冰盖对全球海平面上升贡献的关键因素.
- 这些过程在一年到十年的时间尺度上运行.
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