在最后一次脱冰期间,东太平洋的冷却和大西洋的翻转循环在最后一次脱冰期间发生了变冷
Markus Kienast1, Stephanie S Kienast, Stephen E Calvert
1Department of Oceanography, Dalhousie University, Halifax, Nova Scotia, B3H 4J1 Canada. markus.kienast@dal.ca
Nature
|October 20, 2006
概括
冰河时代的全球气候变化可能源于海洋循环变化. 北大西洋寒冷时期太平洋的冷却表明全球联系,而不仅仅是区域影响.
科学领域:
- 古海洋学是古海洋学.
- 气候科学 气候科学
- 海洋学 海洋学 海洋学
背景情况:
- 在冰川时期的千年规模的气候变化受到辩论.
- 热带太平洋海面温度在这些变化中的作用尚不清楚.
- 之前的研究将北大西洋的寒冷时期与全球气候联系起来,而不是太平洋.
研究的目的:
- 为了研究北大西洋寒冷时期和热带太平洋海面温度之间的联系.
- 为了确定海洋循环变化是否导致全球气候变化.
主要方法:
- 高分辨率的海面温度重建使用烯酸不和.
- 对碳埋葬流程的分析,以推断海洋生产力和上游.
- 考古海洋记录的年代测定,以确定时间同步性.
主要成果:
- 在海因里希事件1期间,东部热带太平洋海面温度下降1°C.
- 在年轻的干事件期间,海面温度下降了~0.5°C.
- 表面海洋生产力的增加是巧合的,这表明在两个寒冷时期的上游增强.
结论:
- 赤道太平洋的冷却与北大西洋的寒冷时期同步发生.
- 这些发现表明,千年规模的气候变化是由海洋热环循环重组驱动的.
- 热带海洋 - 大气相互作用可能放大了这些气候变化.
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