结合倾斜性和前行加速,使得普莱斯托时代晚期降冰的速度提升
1Department of Earth and Planetary Sciences, Harvard University, 20 Oxford Street, Cambridge, Massachusetts 02138, USA. phuybers@fas.harvard.edu
Nature
|December 14, 2011
概括
地球 地球 地球 地球 地球 地球
科学领域:
- 古气候学 古气候学
- 气候科学 气候科学
- 地质物理学 地质物理学
背景情况:
- 建议米兰科维奇周期会影响地球的冰川状态.
- 之前的研究表明,斜率会加快冰川周期的步伐,但前行的作用仍然不清楚.
- 时间的不确定性阻碍了对轨道强迫脱冰的定量测试.
研究的目的:
- 量化测试斜度和前行在普世晚期冰川周期上的双重效应.
- 为了克服分析脱冰轨道节奏的时间控制缺陷.
- 为轨道参数对气候变化的综合影响提供坚实的证据.
主要方法:
- 开发一种新的统计测试,专注于轨道强迫的最大值.
- 对代晚期冰川周期的分析.
- 倾斜和前行效应的分阶段分析.
主要成果:
- 发现倾斜和前行都与普莱斯托时代晚期的冰川周期相匹配.
- 一种新的统计方法成功克服了时间控制问题.
- 结果支持米兰科维奇关于间冰期状态的假设.
结论:
- 斜率和前行协同作用,以加快晚期普世冰川周期的速度.
- 这些发现证实了轨道强迫在脱冰过程中的双重作用.
- 南半球较长的夏季也可能导致脱冰.
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