在过去的400万年中,南大洋的尘埃与气候的结合
Alfredo Martínez-Garcia1, Antoni Rosell-Melé, Samuel L Jaccard
1Geological Institute, ETH Zürich, Zürich 8092, Switzerland. alfredo.martinez-garcia@erdw.ethz.ch
Nature
|August 5, 2011
概括
南大洋的尘埃供应大约在125万年前显著增加,与主要冰河时代的开始相吻合. 这一发现将大气中的尘埃增加与地球联系起来.
科学领域:
- 古气候学和地球系统科学
- 海洋地质化学和沉积物学
- 季度气候动力学 四季度气候动力学
背景情况:
- 大气中的尘埃通过改变辐射平衡和提供铁等海洋微量营养素来影响全球气候.
- 南大洋的尘埃沉积和相关的"铁化肥"与冰川时期大气中二氧化碳的减少有关.
- 南洋尘埃在纪冰川周期中的长期作用仍然不太清楚.
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