气候变化领域集成服务门户(CCPortal): Response of vertical velocities in extratropical precipitation extremes to climate change

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DOI	10.1175/JCLI-D-19-0766.1
	Response of vertical velocities in extratropical precipitation extremes to climate change
	Li Z.; O'Gorman P.A.
发表日期	2020
ISSN	0894-8755
起始页码	7125
结束页码	7139
卷号	33 期号:16
英文摘要	Precipitation extremes intensify in most regions in climate model projections. Changes in vertical velocities contribute to the changes in intensity of precipitation extremes but remain poorly understood. Here, we find that midtropospheric vertical velocities in extratropical precipitation extremes strengthen overall in simulations of twenty-first-century climate change. For each extreme event, we solve the quasigeostrophic omega equation to decompose this strengthening into different physical contributions. We first consider a dry decomposition in which latent heating is treated as an external forcing of upward motion. Much of the positive contribution to upward motion from increased latent heating is offset by negative contributions from increases in dry static stability and changes in the horizontal length scale of vertical velocities. However, taking changes in latent heating as given is a limitation when the aim is to understand changes in precipitation, since latent heating and precipitation are closely linked. Therefore, we also perform a moist decomposition of the changes in vertical velocities in which latent heating is represented through a moist static stability. In the moist decomposition, changes in moist static stability play a key role and contributions from other factors such as changes in the depth of the upward motion increase in importance. While both dry and moist decompositions are self-consistent, the moist dynamical perspective has greater potential to give insights into the causes of the dynamical contributions to changes in precipitation extremes in different regions. © 2020 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).
英文关键词	Climate models; Decomposition; Heating; Velocity; External forcing; Extratropical; Extreme events; Precipitation extremes; Quasi-geostrophic; Static stability; Upward motion; Vertical velocity; Climate change; climate change; climate modeling; extratropical environment; precipitation assessment; precipitation intensity; regional climate
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/171181
作者单位	Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, United States
推荐引用方式 GB/T 7714	Li Z.,O'Gorman P.A.. Response of vertical velocities in extratropical precipitation extremes to climate change[J],2020,33(16).
APA	Li Z.,&O'Gorman P.A..(2020).Response of vertical velocities in extratropical precipitation extremes to climate change.Journal of Climate,33(16).
MLA	Li Z.,et al."Response of vertical velocities in extratropical precipitation extremes to climate change".Journal of Climate 33.16(2020).