在冰川时期,太平洋南部海洋的尘埃沉积增加
F Lamy1, R Gersonde, G Winckler
1Alfred-Wegener-Institut (AWI) Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany.
Science (New York, N.Y.)
|January 25, 2014
概括
在过去的百万年里,南大洋的尘埃沉积量在冰川时期增加了三倍. 整个南太平洋,南极洲和南大西洋的类似模式表明,广泛的气候强迫因素影响了尘埃来源.
科学领域:
- 古气候学 古气候学
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
背景情况:
- 南大洋中的尘埃沉积显著影响了过去的全球气候动态.
- 这种尘埃沉积的时间和地理变化尚未完全理解.
- 极地南太平洋是研究这些变化的最大南大洋区域.
研究的目的:
- 为了重建过去一百万年的南太平洋极地冰川-冰川间尘埃供应周期.
- 将这些循环与其他南大洋地区和潜在来源地区的尘埃记录进行比较.
- 为了确定常见的气候强迫因素,驱动大规模的尘埃沉积模式.
主要方法:
- 分析来自极地南太平洋的尘埃沉积数据.
- 石质沉积物沉积模式与南极和南大西洋尘埃记录的比较.
- 尘埃沉积时间和模式与澳大利亚,新西兰和巴塔哥尼亚等潜在来源地区的相关性.
主要成果:
- 极地南太平洋的尘埃沉积量在冰川时期是过去一百万年间的冰川期之间的三倍.
- 南太平洋的冰川-冰川间尘埃沉积模式与南极洲和南大西洋的尘埃沉积模式相似.
- 这些相似之处表明,共同的气候强迫因素影响了来自澳大利亚,新西兰和巴塔哥尼亚的尘埃供应.
结论:
- 大规模的气候强迫,如南部西风的转移和加强冰川性尘埃动员,影响了南大洋的尘埃沉积.
- 这项研究提供了关于过去南洋尘埃对气候变异性调节的关键数据.
- 了解这些过去的尘埃周期可以增强我们对气候系统相互作用的了解.
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