晚期普莱斯托时代的冰川终点的斜率加速度
1Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA. phuybers@whoi.edu
Nature
|March 26, 2005
概括
地球轨道的斜率,而不是离心率或前行,很可能是导致了普莱斯托纪晚期冰川的终结. 冰盖每隔两到三个倾斜周期就会结束,支持米兰科维奇的原始理论.
科学领域:
- 古气候学 古气候学
- 气候动力学 气候动力学
- 地质物理学 地质物理学
背景情况:
- 晚期普莱斯托时代的冰川 - 间冰川周期 (大约. 700万年) 往往与地球轨道变化有关.
- 现有的模型包括地球的斜率 (大约. 40 kyr),离心率 (大约. 100 kyr),以及前cession (大约. 20 年前).
- 其他假设表明,内部气候变化驱动这些周期.
研究的目的:
- 为了统计测试轨道强迫假设的晚期普莱斯托纪冰川终结.
- 为了确定影响快速脱冰事件的主要轨道参数.
主要方法:
- 对冰川结束时间的统计分析.
- 测试关于独立于斜率,偏心和前行的零假设.
主要成果:
- 冰川终点独立于斜率的零假设在5%的显著性水平上被拒绝.
- 对于离心率和前行率的零假设没有被拒绝.
- 结果表明,冰盖在每第二或第三个倾斜周期结束一次.
结论:
- 地球的斜率是普莱斯托时代晚期冰川终结的主要轨道强迫.
- 这一发现支持米兰科维奇关于轨道影响冰河时代的原始假设.
- 简单的模型表明倾斜强迫可以解释终止时间.
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