气候变化领域集成服务门户(CCPortal): The incorporation of the Tripleclouds concept into the-Eddington two-stream radiation scheme: Solver characterization and its application to shallow cumulus clouds

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DOI	10.5194/acp-20-10733-2020
	The incorporation of the Tripleclouds concept into the-Eddington two-stream radiation scheme: Solver characterization and its application to shallow cumulus clouds
	Crnivec N.; Mayer B.
发表日期	2020
ISSN	1680-7316
起始页码	10733
结束页码	10755
卷号	20 期号:17
英文摘要	The treatment of unresolved cloud-radiation interactions in weather and climate models has considerably improved over the recent years, compared to conventional plane-parallel radiation schemes, which previously persisted in these models for multiple decades. One such improvement is the state-of-The-Art Tripleclouds radiative solver, which has one cloud-free and two cloudy regions in each vertical model layer and is thereby capable of representing cloud horizontal inhomogeneity. Inspired by the Tripleclouds concept, primarily introduced by Shonk and Hogan (2008), we incorporated a second cloudy region into the widely employed-Eddington two-stream method with the maximum-random overlap assumption for partial cloudiness. The inclusion of another cloudy region in the two-stream framework required an extension of vertical overlap rules. While retaining the maximum-random overlap for the entire layer cloudiness, we additionally assumed the maximum overlap of optically thicker cloudy regions in pairs of adjacent layers. This extended overlap formulation implicitly places the optically thicker region towards the interior of the cloud, which is in agreement with the core-shell model for convective clouds. The method was initially applied on a shallow cumulus cloud field, evaluated against a three-dimensional benchmark radiation computation. Different approaches were used to generate a pair of cloud condensates characterizing the two cloudy regions, testing various condensate distribution assumptions along with global cloud variability estimate. Regardless of the exact condensate setup, the radiative bias in the vast majority of Tripleclouds configurations was considerably reduced compared to the conventional plane-parallel calculation. Whereas previous studies employing the Tripleclouds concept focused on researching the top-of-The-Atmosphere radiation budget, the present work applies Tripleclouds to atmospheric heating rate and net surface flux. The Tripleclouds scheme was implemented in the comprehensive libRadtran radiative transfer package and can be utilized to further address key scientific issues related to unresolved cloud-radiation interplay in coarse-resolution atmospheric models. © 2020 BMJ Publishing Group. All rights reserved.
语种	英语
scopus关键词	cloud radiative forcing; cumulus; radiation budget; radiative transfer; top of atmosphere
来源期刊	Atmospheric Chemistry and Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/141098
作者单位	Experimental Meteorology, Ludwig-Maximilians-Universität München, Munich, Germany; Institut für Physik der Atmosphäre, Deutsches Zentrum für Luft-und Raumfahrt, Oberpfaffenhofen, Germany
推荐引用方式 GB/T 7714	Crnivec N.,Mayer B.. The incorporation of the Tripleclouds concept into the-Eddington two-stream radiation scheme: Solver characterization and its application to shallow cumulus clouds[J],2020,20(17).
APA	Crnivec N.,&Mayer B..(2020).The incorporation of the Tripleclouds concept into the-Eddington two-stream radiation scheme: Solver characterization and its application to shallow cumulus clouds.Atmospheric Chemistry and Physics,20(17).
MLA	Crnivec N.,et al."The incorporation of the Tripleclouds concept into the-Eddington two-stream radiation scheme: Solver characterization and its application to shallow cumulus clouds".Atmospheric Chemistry and Physics 20.17(2020).