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关于"床上的摩擦不能控制冰川的快速流动"的评论
Leigh A Stearns1, Cornelis van der Veen2
1Department of Geological Sciences, University of Kansas, Lawrence, KS, USA. stearns@ku.edu.
Science (New York, N.Y.)
|February 9, 2019
概括
这项研究支持结论, 冰川基底摩擦并不能控制冰川的快速流动. 作者澄清了他们的方法,并强调了有关基底滑动和冰川学设置的对立研究的局限性.
科学领域:
- 冰川学
- 地球科学
- 地质学
背景情况:
- 基底摩擦与冰川流动力学之间的关系是冰川学研究的一个关键领域.
- 之前的研究表明冰川床上的摩擦控制了冰川的快速流动, 但作者对这一结论提出了质疑.
- 了解这些动态对于预测冰川的行为和海平面上升至关重要.
研究的目的:
- 为了回应关于基底摩擦不能控制快速冰川流动的批评.
- 进一步证明原研究中使用的方法.
- 解决Minchew等人引用的数值和观察研究的局限性.
主要方法:
- 重新评估和捍卫原始研究的方法.
- 对数值建模研究中的假设进行分析,特别是滑动关系.
- 引用的观察研究适用于特定的冰川学设置的比较.
主要成果:
- 作者的方法进一步得到了验证.
- 由Minchew等人引用的数值研究. 显示依赖于滑动关系,其中滑动速度与基底阻力成比例.
- 由Minchew等人引用的观察研究. 已被证明适用于不同于所研究的冰川环境.
结论:
- 原来的结论是基底摩擦不能控制快速的冰川流动.
- 使用的方法是合理的,适合研究格陵兰的出口冰川.
- 基于某些数值和观测研究的批评受到其基础假设和不同的冰川学背景的限制.
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