气候变化领域集成服务门户(CCPortal): Importance of Laplacian of low-level warming for the response of precipitation to climate change over tropical oceans

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DOI	10.1175/JCLI-D-19-0365.1
	Importance of Laplacian of low-level warming for the response of precipitation to climate change over tropical oceans
	Duffy M.L.; O’Gorman P.A.; Back L.E.
发表日期	2020
ISSN	0894-8755
起始页码	4403
结束页码	4417
卷号	33 期号:10
英文摘要	Several physical mechanisms have been proposed for projected changes in mean precipitation in the tropics under climate warming. In particular, the ‘‘wet-get-wetter’’ mechanism describes an amplification of the pattern of precipitation in a moister atmosphere, and the ‘‘warmer-get-wetter’’ mechanism describes enhanced upward motion and precipitation in regions where the increase in SST exceeds the tropical-mean increase. Studies of the current climate have shown that surface convergence over the tropical oceans is largely driven by horizontal gradients of low-level temperature, but the influence of these gradients on the precipitation response under climate warming has received little attention. Here, a simple model is applied to give a decomposition of changes in precipitation over tropical oceans in twenty-first-century climate model projections. The wet-get-wetter mechanism and changes in surface convergence are found to be of widespread importance, whereas the warmer-get-wetter mechanism is primarily limited to negative anomalies in the tropical southern Pacific. Furthermore, surface convergence is linked to gradients of boundary layer temperature using an atmospheric mixed layer model. Changes in surface convergence are found to be strongly related to changes in the Laplacian of boundary layer virtual temperature, and, to a lesser extent, the Laplacian of SST. Taken together, these results suggest that a ‘‘Laplacian-of-warming’’ mechanism is of comparable importance to wet get wetter and warmer get wetter for the response of precipitation to climate change over tropical oceans. © 2020 American Meteorological Society.
英文关键词	Atmospheric boundary layer; Atmospheric temperature; Climate models; Laplace transforms; Oceanography; Tropics; Boundary layer temperature; Climate warming; Horizontal gradients; Mean precipitation; Mixed-layer models; Physical mechanism; Simple modeling; Virtual temperature; Climate change; climate change; climate modeling; convergence; decomposition analysis; Laplace transform; precipitation (climatology); sea surface temperature; tropical environment; warming; Pacific Ocean; Pacific Ocean (South)
语种	英语
来源期刊	Journal of Climate
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/171301
作者单位	Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, United States; Department of Oceanic and Atmospheric Sciences, University of Wisconsin–Madison, Madison, WI, United States
推荐引用方式 GB/T 7714	Duffy M.L.,O’Gorman P.A.,Back L.E.. Importance of Laplacian of low-level warming for the response of precipitation to climate change over tropical oceans[J],2020,33(10).
APA	Duffy M.L.,O’Gorman P.A.,&Back L.E..(2020).Importance of Laplacian of low-level warming for the response of precipitation to climate change over tropical oceans.Journal of Climate,33(10).
MLA	Duffy M.L.,et al."Importance of Laplacian of low-level warming for the response of precipitation to climate change over tropical oceans".Journal of Climate 33.10(2020).