在阿蒙森海湾观察到的快速岩层升起促进了冰盖的稳定性
Valentina R Barletta1,2, Michael Bevis2, Benjamin E Smith3
1DTU Space, National Space Institute, Geodynamics Department, Technical University of Denmark, Kgs. Lyngby, Denmark. vr.barletta@gmail.com.
概括
阿蒙森海湾 (ASE) 的快速冰川静态调整表明西南极冰盖 (WAIS) 的稳定性可能被低估. 新的GPS数据显示地基岩石的升起速度更快,
科学领域:
- 地质学
- 冰川学
- 气候科学
背景情况:
- 西南极冰层 (WAIS) 在阿蒙森海湾 (ASE) 显著导致全球海平面上升,并面临崩的风险.
- 冰川静态调整 (GIA) 是岩基对冰块质量变化的反应,传统上被认为是一个长期的过程 (10,000年).
研究的目的:
- 通过使用新的GPS测量来研究ASE下的地幔粘度.
- 重新评估该脆弱地区的冰川静态调整 (GIA) 的时间表.
主要方法:
- 利用新的GPS测量来检测阿蒙森海湾 (ASE) 的快速岩层升起.
- 根据观察到的升起速度计算了亚ASE地幔的粘度.
主要成果:
- 在ASE中观察到异常快速的升高41mm/年.
- 确定地幔粘度明显低于全球平均值 (4 x 10^18 Pa·s).
- 将估计的GIA响应时间从几千年缩短到几百年.
结论:
- 快速的GIA表明基岩对冰损失的反应比之前所认为的要快.
- 需要从重力数据上对冰质量损失的估计进行10%的上调.
- 这表明西南极冰层 (WAIS) 面临的灾难性崩可能比以前担心的更稳定.
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