气候变化领域集成服务门户(CCPortal): Opposite tropical circulation trends in climate models and in reanalyses

CCPortal

DOI	10.1038/s41561-019-0383-x
	Opposite tropical circulation trends in climate models and in reanalyses
	Chemke R.; Polvani L.M.
发表日期	2019
ISSN	17520894
英文摘要	The Hadley circulation has large climate impacts at low latitudes by transferring heat and moisture between the tropics and subtropics. Climate projections show a robust weakening of the Northern Hemisphere Hadley circulation by the end of the twenty-first century. Over the past several decades, however, atmospheric reanalyses indicate a strengthening of the Hadley circulation. Here we show that the strengthening of the circulation in the Northern Hemisphere is not seen in climate models; instead, these models simulate a weakening of the circulation in the past 40 years. Using observations and a large ensemble of model simulations we elucidate this discrepancy between climate models and reanalyses, and show that it does not stem from internal climate variability or biases in climate models, but appears related to artefacts in the representation of latent heating in the reanalyses. Our results highlight the role of anthropogenic emissions in the recent slowdown of the atmospheric circulation, which is projected to continue in coming decades, and question the reliability of reanalyses for estimating trends in the Hadley circulation. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/124729
作者单位	Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY, United States; Department of Earth and Environmental Sciences, and Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States
推荐引用方式 GB/T 7714	Chemke R.,Polvani L.M.. Opposite tropical circulation trends in climate models and in reanalyses[J],2019.
APA	Chemke R.,&Polvani L.M..(2019).Opposite tropical circulation trends in climate models and in reanalyses.Nature Geoscience.
MLA	Chemke R.,et al."Opposite tropical circulation trends in climate models and in reanalyses".Nature Geoscience (2019).