在格陵兰岛,融的门反应导致了大规模的床层减弱
Nathan Maier1, Florent Gimbert2, Fabien Gillet-Chaulet2
1Université Grenoble Alpes, CNRS, IGE, Grenoble, France. ntmaier@gmail.com.
Nature
|July 27, 2022
概括
格陵兰岛
科学领域:
- 冰川学
- 气候科学
- 地球系统科学
背景情况:
- 冰盖的动态主要由基底运动控制,受冰床界面上的融水的影响.
- 增加融水可以增强冰下排水,可能增加摩擦并减缓冰流,限制融化驱动的质量损失.
研究的目的:
- 调查融水对格陵兰冰盖动态影响的主要因素.
- 分析格陵兰西部的摩擦变化及其与融化强迫的关系.
主要方法:
- 开发了一种新方法来评估整个冰盖的摩擦变化.
- 分析了融对床的强度的影响,并将它们与基底水储存和排水通道联系起来.
主要成果:
- 强迫融化导致床的强度从北向南发生显著的变化,而不是直接由融化速率解释的.
- 由于基底水储存,格陵兰南部的废弃区减弱了20-40%,而北部则增强了.
- 床的弱化与滑动和水电梯度有关,由陆地终结与海洋终结边缘控制.
结论:
- 冰盖的动态不仅仅取决于融化速度; 基本水储量和边缘类型至关重要.
- 在格陵兰北部,随着气温的上升,由于动态变化而增加的质量损失更有可能发生.
- 发现需要改进的物理表现,以便更准确的百年级冰盖演变模型.
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