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A Rapid Method for Modeling a Variable Cycle Engine
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大西洋南部翻转循环在北北25度减速
Harry L Bryden1, Hannah R Longworth, Stuart A Cunningham
1National Oceanography Centre, Empress Dock, Southampton SO14 3ZH, UK. h.bryden@noc.soton.ac.uk
Nature
|December 2, 2005
概括
自1957年以来,大西洋南部翻转循环的速度已经减慢了30%. 这种显著的减速影响热传输,对气候变化和欧洲天气模式产生影响.
科学领域:
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
- 地球系统科学 地球系统科学
背景情况:
- 大西洋南部翻转循环 (AMOC) 对于全球热量分布至关重要.
- AMOC的热传输显著减轻了欧洲的气候.
- 在AMOC的变化对气候变化有深远的影响.
研究的目的:
- 评估大西洋南部翻转循环 (AMOC) 的变化.
- 为了量化AMOC的热传输变化超过五十年.
- 为了分析AMOC减速的驱动因素.
主要方法:
- 在北方25度处对一个新的跨大西洋海洋学段进行分析.
- 与1957年至2004年间的四个历史跨大西洋部分进行比较.
- 量化不同深度的水质运输.
主要成果:
- 大西洋南部翻转循环 (AMOC) 在1957年至2004年期间减速了约30%.
- 在北极25度的海湾流向北传输的热量仍然相对不变.
- 观察到热水的南向循环增加和深水的南向运输减少.
结论:
- 观察到的AMOC减速归因于亚热带旋转中循环模式的变化.
- 不太深的水正在向南返回,这表明循环的深层肢体正在减弱.
- 这些变化对未来的气候预测有重大影响.
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