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使用ICESat-2卫星高度计估活跃的冰下湖泊的有效压力
Aaron Stubblefield1,2, Aleah Nicholson Sommers3, Colin Meyer3
1Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, USA.
概括
研究人员开发了一种新方法,利用卫星高度测量来估计南极冰盖下方的有效压力. 这种技术有助于了解水流和冰的滑动,揭示压力通常接近浮动,但有时达到冰的抗拉强度.
科学领域:
- 冰川学的冰川学
- 地质物理学 地质物理学
- 水文学 水文学
背景情况:
- 有效压力 (冰压与水压) 控制了冰流和冰床界面的滑动.
- 直接的亚冰川测量是罕见的,使得亚冰川水文模型依赖于间接量化.
- 活跃的冰下湖泊提供了一个独特的机会,通过表面高度变化来限制有效压力.
研究的目的:
- 开发和应用一种新的方法,用卫星高度测量数据来估计冰下有效压力.
- 为了将亚冰川湖面上的地表升高异常与亚冰川水体积变化联系起来.
- 为亚冰川水文模型和冰川动态提供新的约束.
主要方法:
- 综合了现有的亚冰川湖有效压力理论与基于高度测量的反向方法.
- 相关的地表高度变化与亚冰川水体积波动.
- 将该方法应用于ICESat-2卫星高度测量数据在南极洲的冰湖下.
主要成果:
- 有效压力通常代表过载压力的一小部分 (约10kPa).
- 观察到更大的有效压力,有时超过100kPa,接近冰的抗拉强度.
- 这些偏差与高冰粘度时期有关.
结论:
- 开发的方法成功估计了活跃的冰下湖泊上方的有效压力.
- 这些发现为完善亚冰川水文模型提供了关键数据.
- 结果为南极洲的冰川床相互作用和动态提供了新的见解.
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