松岛冰川在 holocene 早期的快速稀释
J S Johnson1, M J Bentley, J A Smith
1British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK.
概括
松岛冰川在全新世纪早期经历了快速稀薄,类似于今天. 这种古老的冰损失,是由冰架变化驱动的,持续了几个世纪,突出了长期的冰盖不稳定性.
科学领域:
- 冰川学的冰川学
- 古气候学 古气候学
- 西南极洲冰盖的动态 西南极洲冰盖的动态
背景情况:
- 松岛冰川 (PIG) 是西南极冰盖的一个主要出口冰川.
- 在过去的二十年中,PIG表现出显著的稀薄和退缩.
研究的目的:
- 为了调查过去的松岛冰川快速稀释事件.
- 为了比较早期Holocene稀释率与当代变化.
主要方法:
- 利用了冰川地质数据.
- 采用了地质年代学技术,特别是宇宙学 (10) 测定冰川运输的岩石的年代.
主要成果:
- 松岛冰川在大约8000年前在早期的全新纪期间经历了快速稀释.
- 稀释速度超过100厘米/年,持续数十年到几个世纪.
- 这种过去的稀释与当前的速度相似,可能是由于冰架支力的减少造成的.
结论:
- 松岛冰川有着快速稀释事件的历史.
- 一旦启动,该地区的快速冰盖变化可能会持续很长时间,持续几个世纪.
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