海洋热量迫使西南极洲冰盖在最后一个冰川最大期之后撤退
Elaine M Mawbey1, James A Smith2, Claus-Dieter Hillenbrand1
1British Antarctic Survey, High Cross, Madingley Road, Cambridge, UK.
Nature communications
|February 6, 2026
概括
温暖的海洋水导致西南极洲冰盖在最后一次降冰期间退缩. 随后的冷却使冰盖稳定,表明海洋热量,而不是大气变暖,主要控制其长期稳定性.
科学领域:
- 古海洋学是古海洋学.
- 冰川学的冰川学
- 气候科学 气候科学
背景情况:
- 西南极冰盖 (WAIS) 由于温暖的环极深水 (CDW) 融化而迅速变薄.
- 由于历史数据有限,对WAIS稳定性的长期海洋温度影响仍然不确定.
研究的目的:
- 在过去的18,000年里重建过去的海洋温度和水质属性.
- 调查海洋热量对WAIS稳定性的影响,自最后一个冰川最大期以来.
主要方法:
- 对基基菌 Mg/Ca 和 δ13C 记录的分析.
- 来自阿蒙森海的沉积物核心分析.
主要成果:
- 温暖的CDW存在于大陆架上从约18.0到10.1 kyr BP,与显著的WAIS撤退相吻合.
- 在大约10.1 kyr BP之后的海洋冷却导致冰盖稳定,没有观察到主要的接地线撤退.
- 在Holocene中期的大气变暖并没有导致WAIS进一步退缩,强调海洋热量是主导因素.
结论:
- 海洋热量,特别是CDW,是最后一次降冰期间WAIS撤退的主要驱动因素.
- WAIS的稳定性与过去的海洋条件,特别是底层水温密切相关.
- 了解长期的海洋冰相互作用对于预测未来的冰盖行为至关重要.
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