模拟了最后一次冰川时期海洋反对轨道强迫的放大
M Khodri1, Y Leclainche, G Ramstein
1LSCE, CF-Saclay, 91191, Gif sur Yvette, France. khodri@lsce.saclay.cea.fr
Nature
|March 30, 2001
概括
较低的夏季太阳辐射在115,000年前开始了冰河时代. 海洋反放大了这种冷却,在高度增加了雪,并解释了最后一次冰川的开始.
科学领域:
- 古气候学 古气候学
- 气候建模气候模型
背景情况:
- 米兰科维奇理论认为,夏季阳光照射减少引发了过去的冰川.
- 之前的气候模型未能仅仅使用阳光强迫来模拟最后一次冰河.
研究的目的:
- 为了研究海洋-大气反在扩大轨道强迫在最后一次冰川时期的作用.
- 为了模拟冰盖的积累,使用结合的海洋大气模型.
主要方法:
- 利用一个完全合的海洋-大气模型.
- 强迫模型与与最后一次冰河相关的阳光照射变化.
主要成果:
- 在关键的冰盖位置成功模拟了多年积雪的积累.
- 证明海洋反会导致高度地区的冷却.
- 显示了极地大气湿度转移的增加.
结论:
- 海洋的反对于放大弱轨道强迫和启动冰期至关重要.
- 该模型的结果与过去冰盖的地质证据一致.
- 这种机制解释了最后一个冰川时期的开始,可能被植被变化放大.
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