气候变化领域集成服务门户(CCPortal): Global Impact of Cloud Longwave Scattering in an Atmosphere-Only General Circulation Model Simulation

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DOI	10.1029/2020JD033968
	Global Impact of Cloud Longwave Scattering in an Atmosphere-Only General Circulation Model Simulation
	Gu B.; Ren T.; Kuo C.-P.; Yang P.; Bowman K.
发表日期	2021
ISSN	2169897X
卷号	126 期号:3
英文摘要	Most general circulation models (GCMs) neglect cloud longwave scattering in pursuit of computational efficiency. This study implements the 2-/4-stream (2/4S) method, a relatively fast cloud longwave scattering treatment, in Community Atmospheric Model version 5 (CAM5) to analyze the impact of cloud longwave scattering on the large-scale circulation. Two 45-years-long integrations are performed with prescribed sea surface temperature (SST). In the experiment run, cloud longwave scattering is included using the 2/4S method; in the control run, clouds only absorb in the longwave. The results show that cloud longwave scattering acts to enhance the cloud longwave (greenhouse) effect by reducing outgoing longwave radiation (OLR) and enhancing downward longwave irradiance at the surface. The OLR reduction is most significant over the tropics, where surface temperatures and cloud elevations are high. The surface downward irradiance increase is most significant over polar areas and the Tibetan Plateau, where cloud elevations are low and the air below clouds is dry. Inclusion of cloud longwave scattering enhances the Walker circulation, suggestive of the importance of diabatic radiative heating in the tropical circulation. Inclusion of cloud longwave scattering also appears to shift the eddy-driven jet poleward in the austral summer in the Southern Hemisphere, suggesting that the cloud longwave effect plays a role in shaping the jet position. Persistent equatorward jet biases in GCMs may be reduced if cloud longwave scattering is considered. © 2021. American Geophysical Union. All Rights Reserved.
语种	英语
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185519
作者单位	Department of Atmospheric Sciences, Texas A&M University, College Station, TX, United States; Cooperative Institute for Research in the Atmosphere, Fort Collins, CO, United States
推荐引用方式 GB/T 7714	Gu B.,Ren T.,Kuo C.-P.,et al. Global Impact of Cloud Longwave Scattering in an Atmosphere-Only General Circulation Model Simulation[J],2021,126(3).
APA	Gu B.,Ren T.,Kuo C.-P.,Yang P.,&Bowman K..(2021).Global Impact of Cloud Longwave Scattering in an Atmosphere-Only General Circulation Model Simulation.Journal of Geophysical Research: Atmospheres,126(3).
MLA	Gu B.,et al."Global Impact of Cloud Longwave Scattering in an Atmosphere-Only General Circulation Model Simulation".Journal of Geophysical Research: Atmospheres 126.3(2021).