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Updated: Jun 24, 2026

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Study of Protein Dynamics via Neutron Spin Echo Spectroscopy
Published on: April 13, 2022
厄尔尼诺-南方振荡在冰川-冰川间周期的变化
A W Tudhope1, C P Chilcott, M T McCulloch
1Department of Geology & Geophysics, Edinburgh University, Edinburgh, EH9 3JW, UK. mail: sandy.tudhope@ed.ac.uk
概括
厄尔尼诺-南方振荡 (ENSO) 持续了13万年,甚至在冰川时期. 然而,ENSO在20世纪的活动比之前的温暖和凉爽时期更强大.
科学领域:
- 古气候学 古气候学
- 气候科学 气候科学
- 海洋学 海洋学 海洋学
背景情况:
- 厄尔尼诺-南方振荡 (ENSO) 是全球年度间气候变化的主要驱动因素.
- 了解ENSO对气候变化的敏感性至关重要,因为温室气体变暖影响的不确定性.
- 过去的ENSO行为提供了对其对不同气候条件的反应的见解.
研究的目的:
- 调查过去13万年来ENSO的历史行为和变化.
- 为了确定ENSO是否在过去的冰川和冰川间时期运行.
- 为了比较ENSO在20世纪的强度与它在以前的气候状态中的行为.
主要方法:
- 来自巴布亚新几内亚的每年带带的珊瑚骨的分析.
- 从珊瑚记录中使用地化学代理来重建过去的ENSO活动.
- 在不同古气候条件 (冰期,冰期间和20世纪) 中对ENSO振幅进行比较.
主要成果:
- 证据表明,ENSO至少存在了13万年,包括在降温和改变太阳强迫的冰川时期.
- 在20世纪,ENSO活动的幅度明显高于之前的冰川和冰川间时期的幅度.
- 恩索的振幅似乎在寒冷的冰川条件下减弱,并受到 precessional 轨道变化的影响.
结论:
- 恩索是一个长期存在的气候现象,能够抵御过去的重大气候变化.
- 20世纪经历了一段相对于ENSO长期历史的增强ENSO活动的时期.
- 恩索振幅的变化可能与冰川气候状态和轨道强迫之间的相互作用有关.
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