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19,000年前海平面迅速上升及其全球影响
Peter U Clark1, A Marshall McCabe, Alan C Mix
1Department of Geosciences, Oregon State University, Corvallis, OR 97331, USA. clarkp@geo.oregonstate.edu
Science (New York, N.Y.)
|May 25, 2004
概括
显著的海平面上升,或融水脉冲,发生在19,000年前,起源于北半球冰盖. 这一事件使北大西洋变冷,同时使热带和南半球变暖.
科学领域:
- 古气候学 古气候学
- 海洋学 海洋学 海洋学
- 冰川学的冰川学
背景情况:
- 降冰期间的海平面变化和气候动态对于了解地球气候系统至关重要.
- 北半球冰盖在突然气候变化中的作用需要进一步调查.
研究的目的:
- 为了调查海平面急剧上升事件的时间和来源,大约19,000年前 (B.P. ) 的情况.
- 为了阐明驱动全球气候对这种融水脉冲反应的机制.
主要方法:
- 对爱尔兰海盆地证据的分析.
- 检查气候记录,包括北大西洋深水形成和海洋温度.
主要成果:
- 证据支持19,000年B.P.海平面急剧上升 (融水脉冲). 在爱尔兰海盆地.
- 北大西洋深水形成的减少和北大西洋的冷却与融水脉冲相吻合.
- 热带大西洋,太平洋和南半球发生了同时的变暖.
结论:
- 融水脉冲很可能起源于北半球冰盖.
- 该研究确定了全球传播脱冰气候信号的机制,解释了北半球的降温和南半球的变暖.
