气候变化领域集成服务门户(CCPortal): Improved clouds over Southern Ocean amplify Antarctic precipitation response to ozone depletion in an earth system model

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DOI	10.1007/s00382-020-05346-8
	Improved clouds over Southern Ocean amplify Antarctic precipitation response to ozone depletion in an earth system model
	Schneider D.P.; Kay J.E.; Lenaerts J.
发表日期	2020
ISSN	0930-7575
起始页码	1665
结束页码	1684
卷号	55
英文摘要	Increasing precipitation on the Antarctic Ice Sheet (AIS) in a warming climate has the potential to partially mitigate Antarctica’s contribution to sea level rise. We show that a simple, physically motivated change to the shallow convective cloud phase in the Community Earth System Model (CESM)—improving a long-standing bias in shortwave cloud forcing over the Southern Ocean—leads to an enhanced response of precipitation when the model is forced with realistic stratospheric ozone depletion, with other radiative forcing remaining constant. We analyze two ozone-forced ensemble experiments with the CESM version 1.1: one using the standard version of the model and the other using the cloud-modified version. The standard version exhibits a precipitation increase on the AIS of 34 gigatons year−1; the cloud-modified version shows an increase of 109 Gt year−1. The cloud-modified version shows a more robust, year-round poleward shift in the westerly jet and storm tracks, which brings more precipitation to the AIS, compared to the standard version. Greater surface warming and larger-amplitude stationary waves further increase the Antarctic precipitation response. The enhanced warming in the cloud-modified version is explained by larger positive shortwave cloud feedbacks, while the enhanced poleward jet shift is associated with a stronger meridional temperature gradient in the upper troposphere—lower stratosphere. These results illustrate (1) the sensitivity of forced changes in Antarctic precipitation to the mean state of a climate model and (2) the strong role of atmospheric dynamics in driving that forced precipitation response. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Antarctic ice sheet; Precipitation; Shortwave cloud feedbacks; Structural uncertainty
语种	英语
scopus关键词	climate change; cloud; convection; ozone depletion; precipitation (climatology); sea level change; shortwave radiation; warming; Antarctic Ice Sheet; Antarctica; Southern Ocean
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/145343
作者单位	Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, United States; Cooperative Institute for Research in Environmental Sciences, University of Colorado – Boulder, Boulder, CO, United States; Department of Atmospheric and Oceanic Sciences, University of Colorado – Boulder, Boulder, CO, United States
推荐引用方式 GB/T 7714	Schneider D.P.,Kay J.E.,Lenaerts J.. Improved clouds over Southern Ocean amplify Antarctic precipitation response to ozone depletion in an earth system model[J],2020,55.
APA	Schneider D.P.,Kay J.E.,&Lenaerts J..(2020).Improved clouds over Southern Ocean amplify Antarctic precipitation response to ozone depletion in an earth system model.Climate Dynamics,55.
MLA	Schneider D.P.,et al."Improved clouds over Southern Ocean amplify Antarctic precipitation response to ozone depletion in an earth system model".Climate Dynamics 55(2020).