在过去的116,000年里,在巴西亚热带地区,阳光照射导致大气循环的变化
Francisco W Cruz1, Stephen J Burns, Ivo Karmann
1Department of Geosciences, University of Massachusetts, Amherst, 01002 Massachusetts, USA. fdacruz@geo.umass.edu
Nature
|March 4, 2005
概括
丹斯加德-奥什格尔周期影响了热带水文循环,影响了巴西的降雨量. 然而,这些千年规模的气候变化不像北半球那样占主导地位.
科学领域:
- 古气候学 古气候学
- 气候动力学 气候动力学
- 南美气候历史 南美气候历史
背景情况:
- 千年规模的温度振荡,称为丹斯加尔德-奥什格尔周期,是北半球在最后一个冰川时期的主导气候信号.
- 丹斯加德-奥什格尔周期对热带和亚热带南半球的影响程度,特别是其水文周期,仍然不确定.
- 太阳化变化是由地球的周期周期驱动的,被认为是南半球的主要直接气候强迫因素.
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