在普略世的温暖时期冷却拉尼娜?
1Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK.
概括
过去温暖时期的厄尔尼诺-南方振荡 (ENSO) 动态受到辩论. 有证据表明,在普略世时代盛行的是类似拉尼娜的状态,而不是厄尔尼诺,这表明了"海洋恒温器"效应.
科学领域:
- 古气候学 古气候学
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
背景情况:
- 厄尔尼诺-南方振荡 (ENSO) 在全球变暖和气候变化中的作用受到辩论.
- 了解过去的ENSO状态对于预测未来的气候反应至关重要.
研究的目的:
- 为了研究ENSO在温暖的早期至中期新纪时期的条件.
- 为了测试持续的厄尔尼诺状况与动态海洋反应的假设.
主要方法:
- 使用普略世古热度计重建了海面温度.
- 分析了在赤道太平洋地区热线倾斜和上游的证据.
主要成果:
- 发现了增强热线倾斜和冷涌的证据,表明类似于拉尼娜的状态.
- 在此期间,持久的温暖的厄尔尼诺状况与之前的建议相矛盾.
- 观察到一个动态的"海洋恒温器",其中热带太平洋的加热导致东部的冷却.
结论:
- 早期至中期的普略纪可能出现了动态的ENSO,有利于类似于拉尼娜的条件.
- 这表明一个令人惊叹的结果.
- 海洋恒温器海洋恒温器
- 它是调节热带太平洋温度的机制.
- 研究结果提供了关于在持续变暖情景下海洋与大气相互作用的见解.
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