在过去的80万年里,来自EPICA Dome C冰芯的尘土气候合
F Lambert1, B Delmonte, J R Petit
1Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland.
Nature
|April 4, 2008
概括
冰川时期显示出尘埃流和南极温度之间有很强的联系,与冰川间时期不同. 较冷的气候增强了这种尘埃温度的相关性,这表明南极和较低度气候之间的合增加了.
科学领域:
- 古气候学 古气候学
- 大气科学 大气科学
- 地质化学 地质化学
背景情况:
- 太阳系尘埃影响地球的辐射平衡和海洋营养供应.
- 冰川 - 冰川间时间尺度上的气候变化可能会影响尘埃周期.
研究的目的:
- 研究过去八个气候周期中尘埃流和气候之间的关系.
- 了解在冰川时期控制尘埃输入的因素.
主要方法:
- 在东南极洲的EPICA Dome C冰芯中高分辨率分析岩尘埃.
- 尘埃流量记录与南极温度记录的比较.
主要成果:
- 在冰川时期发现了尘埃流量和温度之间的显著相关性,但不是在冰川间时期.
- 尘埃流与南极温度的相关性随着气候降温而增加.
- 大气传输时间的有限变化表明,尘埃来源和寿命是高冰川尘埃输入的关键.
结论:
- 这项研究表明,南极和低度气候逐渐与更冷的条件相结合.
- 增加的冰川尘埃流量归因于加强了南美尘埃来源和更长的大气尘埃颗粒寿命,这是由于降低了冰河时代的水文循环.
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