最近北半球热带扩张主要是由黑碳和热层臭氧驱动的
Robert J Allen1, Steven C Sherwood, Joel R Norris
1Department of Earth Sciences, University of California, Riverside 92521, USA. rjallen@ucr.edu
Nature
|May 19, 2012
概括
黑碳和热层臭氧气溶是北半球热带扩张的主要驱动因素,与温室气体不同. 这些变暖剂改变了大气循环,重新调整了气候区.
科学领域:
- 大气科学 大气科学
- 气候科学 气候科学
- 环境科学 环境科学
背景情况:
- 观测研究表明,热带的扩大与全球变暖有关.
- 热带扩张影响大气循环和气候区转移.
- 南半球的扩张与臭氧层的减少有关,但北半球的驱动因素仍然不清楚,模型无法复制.
研究的目的:
- 调查北半球热带扩张的驱动因素.
- 确定气溶与温室气体在热带扩张中的作用.
- 为了解释观察到的热带扩张的夏季最大值.
主要方法:
- 使用了气候模型,详细介绍了气溶物理.
- 模拟了温室气体,黑碳气溶和热层臭氧的影响.
- 分析了大气加热对中度和热层喷流的影响.
主要成果:
- 黑碳和热层臭氧气溶的增加在推动热带扩张方面比温室气体更有效.
- 这些气溶可以解释观测到的夏季热带扩张的最大值.
- 在中度的气溶引起大气加热,导致热层喷气向极点转移.
结论:
- 黑碳和热层臭氧是北半球热带扩张的最可能的原因.
- 人类活动显著影响这些气溶剂.
- 需要进一步的研究来调查模型的不敏感性,并完善气溶强迫估计.
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