这是一个很好的例子. 在最后一个冰川时期,一个温暖而通风不良的深北极地中海
D J R Thornalley1, H A Bauch2, G Gebbie3
1Woods Hole Oceanographic Institution (WHOI), Woods Hole, MA 02543, USA. Department of Geography, University College London, London WC1E 6BT, UK.
概括
北极地中海 (AM) 的冰川空气通风不佳,而且比今天更热. 这种深水的降冰混合可能有助于融化冰盖和海冰.
科学领域:
- 海洋学
- 古气候学
- 气候科学
背景情况:
- 北极地中海 (AM) 密集水形成的变化影响全球气候.
- 了解过去的AM循环是重建冰川时期气候动态的关键.
研究的目的:
- 为了重建过去3万年来AM循环的变化
- 在冰川时期和脱冰过程中研究深层AM的通风和温度.
主要方法:
- 在北欧深海的放射性碳通风年龄的重建.
- 对深度AM温度变化的代理数据的分析.
主要成果:
- 冰川深度的AM表现出极其糟糕的通风,年龄高达1万年.
- 北大西洋的老化深水在脱冰过程中出现过度溢出.
- 深冰期的AM比现在的温度高2°3°C.
结论:
- 低通风和高温是冰川深度AM的特征.
- 降冰过程中AM的脱水可能影响了海冰,冰山和冰盖融化.
- AM循环变化是冰川间气候变化的重要因素.
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