太阳能强迫区域气候变化在马恩德最小值期间
D T Shindell1, G A Schmidt, M E Mann
1NASA Goddard Institute for Space Studies and Center for Climate Systems Research, Columbia University, New York, NY 10025, USA.
概括
太阳辐射的变化导致了全球温度的轻微变化,但北半球大陆的区域降温显著. 这种气候反应与北极振荡/北大西洋振荡状态有关.
科学领域:
- 气候科学是气候科学.
- 古气候学 古气候学
- 大气科学 大气科学
背景情况:
- 蒙德极小值 (17世纪末) 代表了太阳活动较低的时期.
- 了解过去的气候变化对于预测未来的气候变化至关重要.
研究的目的:
- 为了研究气候对太阳辐射变化的反应,在莫恩德最小值和18世纪末之间.
- 分析全球和区域温度变化.
主要方法:
- 利用气候模型来模拟气候反应.
- 采用经验重建和表面温度的代理数据.
主要成果:
- 全球平均气温的变化最小 (0.3-0.4°C).
- 观察到显著的区域温度变化,特别是冬季北半球大陆的寒冷条件 (1-2°C).
- 气候模型结果表明,北极振荡/北大西洋振荡向低指数状态的转变.
结论:
- 太阳辐射的变化对区域气候模式产生重大影响,即使全球平均温度的变化很小.
- 北极振荡/北大西洋振荡在调解区域气候对太阳强迫反应方面发挥着关键作用.
- 模型的发现与历史记录和代理数据保持一致,验证了模拟的气候反应.
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