百年级的气候冷却与一个突然的寒冷事件大约8,200年前
Eelco J Rohling1, Heiko Pälike
1Southampton Oceanography Centre, Southampton SO14 3ZH, UK. E.Rohling@soc.soton.ac.uk
Nature
|April 23, 2005
概括
在全新纪期间的气候变化是有争议的. 大约8200年前,与北大西洋深水减速相关的格陵兰岛显著的温度异常使全球气候异常评估变得复杂.
科学领域:
- 古气候学 古气候学
- 气候科学 气候科学
- 四年纪地质学四年纪地质学
背景情况:
- 全新世气候变化仍然是科学辩论的主题.
- 格陵兰冰芯 (8,2008,100年前) 的显著温度异常与北大西洋融水事件有关.
- 这一事件对于了解北大西洋新鲜化及其全球影响至关重要.
研究的目的:
- 为了研究全新世纪气候信号的复杂性.
- 为了澄清8200年前的事件与更长期的气候模式之间的关系.
- 为了确定快速冷却事件的地理范围和影响.
主要方法:
- 对格陵兰岛中部冰芯温度记录的分析.
- 全球气候代理记录与格陵兰异常的相关性.
- 检查气候异常的时间和持续时间.
主要成果:
- 全球气候异常常常与格陵兰事件相关,但跨度为400600年,比它更早.
- 在Holocene中观察到更长期的冷却模式.
- 8,200年前的冷却似乎叠加在这些事先存在的趋势上.
结论:
- 全新纪气候信号的复杂性质使北大西洋深水减速影响的直接评估变得复杂.
- 远场气候异常不能直接归因于8200年前的事件.
- 需要进一步的研究来确定快速冷却事件的全部地理范围.
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