格陵兰中部的全新纪稀薄,由东北格陵兰冰流控制
Ilaria Tabone1,2,3, Alexander Robinson4,5, Marisa Montoya4,6
1Departamento de Geofísica, Universidad de Concepción, Concepción, Chile. itabone@dgeo.udec.cl.
Nature communications
|July 31, 2024
概括
格陵兰冰盖在全新纪期间的稀薄受到了冰流动力学的影响. 格陵兰东北部的撤退引发了海拔变化,解释了超过一半的观察到的冰层稀释.
科学领域:
- 冰川学的冰川学
- 古气候学 古气候学
- 地球系统科学 地球系统科学
背景情况:
- 全新世冰芯记录显示,格陵兰冰盖在广泛地变薄.
- 数值冰川学模型往往低估了这种稀释,引发了对模型准确性的担忧.
- 东北格陵兰冰流 (NEGIS) 可能影响了格陵兰冰盖早期的动态.
研究的目的:
- 为了调查NEGIS动态在Holocene冰盖稀释中的作用.
- 为了确定格陵兰东北部的接地线撤退是否会影响格陵兰中部冰盖的升高.
- 评估冰流动力学对全新纪地表海拔变化的贡献.
主要方法:
- 对冰盖动态的数值模拟.
- 在格陵兰东北部模拟接地线撤退.
- 分析格陵兰岛中部冰盖升高的冰动态影响.
主要成果:
- 格陵兰东北部的接地线撤退引发了北方山峰的海拔变化.
- 快速的冰流流,由降低基底剪压驱动,解释了55% (±18%) 估计的冰稀释.
- 格陵兰东北部的冰流动力学显著影响格陵兰中部的冰面海拔变化.
结论:
- 冰流动力学是格陵兰中部全新纪地表海拔降低的主要驱动因素.
- 古代NEGIS系统调节了影响格陵兰冰盖稀释的冰动态效应.
- 对冰流动力学的准确建模对于了解过去和未来的冰盖行为至关重要.
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