自中生代以来一直活跃的厄尔尼诺-南方振荡
Xiang Li1,2, Shineng Hu2, Yongyun Hu1,3
1Laboratory for Climate and Ocean-Atmosphere Studies, Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China.
概括
在过去的2.5亿年里,厄尔尼诺-南方振荡 (ENSO) 的强度发生了变化. 海洋深度和大气噪声的变化主要由ENSO控制.
科学领域:
- 古气候学 古气候学
- 气候动力学 气候动力学
- 海洋学 海洋学 海洋学
背景情况:
- 厄尔尼诺-南方振荡 (ENSO) 是全球气候变化的主要驱动因素.
- 了解ENSO的长期演变对于预测未来的气候变化至关重要.
- 过去的ENSO在地质时间尺度上的行为仍然不太了解.
研究的目的:
- 调查过去2.5亿年来ENSO的历史行为和变化.
- 确定控制ENSO在不同地质时期的振幅波动的关键因素.
主要方法:
- 结合时间切片气候模拟的分析.
- 在过去的2.5亿年中,由古地理学,大气中的二氧化碳和太阳辐射数据在1000万年间隔进行模拟.
- 使用线性稳定性分析来确定影响ENSO振幅的因素.
主要成果:
- 在过去的2.5亿年里,ENSO一直是热带海洋表面温度变化的主要模式.
- 在不同地质时期,ENSO的振幅有显著的变化.
- ENSO振幅的变化主要是由热点深度和大气噪声的变化驱动的,这解释了76%的周期间变化.
结论:
- 海洋垂直热结构 (热线深度) 和大气噪声是ENSO振幅的关键调节器.
- 这些发现强调了这些因素对于了解过去的ENSO动态和预测未来ENSO变化的重要性.
- 该研究提供了对未来ENSO变化的不确定性的见解.
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