相关实验视频
Updated: Jun 5, 2026

07:28
Evolution of Staircase Structures in Diffusive Convection
Published on: September 5, 2018
北大西洋深层对流的脱冰进化
David J R Thornalley1, Stephen Barker, Wallace S Broecker
1School of Earth and Ocean Sciences, Cardiff University, Cardiff, CF10 3YE, UK. d.thornalley@cantab.net
概括
北大西洋深水形成对于海洋循环和气候调节至关重要,在寒冷时期减少. 这允许南极中间水进入,影响大气循环.
科学领域:
- 海洋学 海洋学 海洋学
- 古气候学 古气候学
- 气候科学 气候科学
背景情况:
- 北大西洋的深水形成是大西洋翻转循环和全球气候调节的关键.
- 开放的海洋对流驱动了这种深水形成过程.
研究的目的:
- 调查自最后一个冰川最大期以来北大西洋深水形成和对流的变化.
- 了解北大西洋对流和全球气候调节之间的关系.
主要方法:
- 利用水柱放射性碳重建来分析过去的对流模式.
- 在东北和西北大西洋之间的深度对流中比较时间变化.
主要成果:
- 在东北大西洋在寒冷的间隔内推断减少了开放海洋对流.
- 在这些寒冷时期确定了极为放射性碳贫乏的南极中间水的入侵.
- 观察到,东北和西北大西洋的对流减少是解释大气循环变化的必要条件.
结论:
- 东北大西洋对流活动显著影响格陵兰的气温.
- 北大西洋公海对流的同步减少与大气循环中的扰动有关.
- 南极洲中间水的入侵与冰川寒冷阶段的深水形成减少有关.
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