20世纪初全球变暖的模拟
1Geophysical Fluid Dynamics Laboratory (GFDL)/National Oceanic and Atmospheric Administration, Princeton, NJ 08542, USA.
概括
全球变暖发生在两个不同的时期. 气候模型模拟表明,20世纪初的变暖是人类对温室气体的强迫和自然海洋大气变化的结果.
科学领域:
- 气候科学 气候科学
- 地球系统科学 地球系统科学
- 古气候学 古气候学
背景情况:
- 全球变暖已经在两个不同的时期被观察到: 1925-1944年和1978年至今.
- 后期的变暖时期是由于温室气体增加,但早期变暖的原因不太清楚.
研究的目的:
- 为了调查20世纪初全球变暖的原因.
- 确定人类诱导的辐射强迫和内部气候变异在历史变暖时期的作用.
主要方法:
- 利用一个合的海洋大气气候模型.
- 进行了六次与特定的时间变化的人为诱导辐射强迫的整合.
- 分析模型输出,以评估对变暖的贡献.
主要成果:
- 模型模拟表明,20世纪初的变暖 (1925年至1944年) 可能源于人类辐射强迫和自然多十年变化的结合.
- 相对贡献取决于模型的气候灵敏度和内部可变性.
结论:
- 内部的多十年变化可能在20世纪初的全球变暖中发挥了重要作用.
- 了解自然变化对于归因历史气候变化至关重要.
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