模拟的千年规模的气候变化,由一个对流 - 引流振荡器驱动
Yvan M Romé1, Ruza F Ivanovic1, Lauren J Gregoire1
1School of Earth and Environment, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT UK.
概括
一个新的对流 - 引流振荡器机制解释了千年规模的气候变化和在最后一个冰川时期的气候突然变化. 这个模型将丹斯加尔德-奥什格尔周期与大西洋翻转南流动 (AMOC) 动态的变化联系起来.
科学领域:
- 古气候学 古气候学
- 气候动力学 气候动力学
- 海洋学 海洋学 海洋学
背景情况:
- 最后一个冰河时期出现了千年的气候变化,包括突然的丹斯加尔德-奥斯格尔 (D-O) 周期.
- 这些周期与大西洋翻转南部循环 (AMOC) 的变化有关,但确切的机制尚不清楚.
研究的目的:
- 介绍并解释对流 - 引流振荡器机制.
- 为了解气候模型中的千年级波动和突然气候变化提供一个框架.
主要方法:
- 利用HadCM3的一般循环模型模拟.
- 强制模拟与淡化融水历史的快照.
- 分析了千年规模的振荡和AMOC制度的变化.
主要成果:
- 对流 - 引流振荡器机制解释了千年规模的振荡.
- 该机制涉及快速对流和缓慢对流组成部分,影响北大西洋分层和盐度.
- 在特定的背景条件和淡水释放模式下发生振荡,导致全球盐分重组.
结论:
- 对流 - 引流振荡器为突然的气候变化和AMOC制度转变提供了新的解释.
- 这种机制扩展了有关千年气候变化的现有理论.
- 这些发现为理解一般循环模型中的气候动态提供了一个一般框架.
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