气候变化领域集成服务门户(CCPortal): The Impact of Resolving Subkilometer Processes on Aerosol-Cloud Interactions of Low-Level Clouds in Global Model Simulations

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DOI	10.1029/2020MS002274
	The Impact of Resolving Subkilometer Processes on Aerosol-Cloud Interactions of Low-Level Clouds in Global Model Simulations
	Terai C.R.; Pritchard M.S.; Blossey P.; Bretherton C.S.
发表日期	2020
ISSN	19422466
卷号	12 期号:11
英文摘要	Subkilometer processes are critical to the physics of aerosol-cloud interaction (ACI) but have been dependent on parameterizations in global model simulations. We thus report the strength of ACI in the Ultra-Parameterized Community Atmosphere Model (UPCAM), a multiscale climate model that uses coarse exterior resolution to embed explicit cloud-resolving models with enough resolution (250 m horizontal, 20 m vertical) to quasi-resolve subkilometer eddies. To investigate the impact on ACIs, UPCAM's simulations are compared to a coarser multiscale model with 4 km horizontal resolution. UPCAM produces cloud droplet number concentrations (Nd) and cloud liquid water path (LWP) values that are higher than the coarser model but equally plausible compared to observations. Our analysis focuses on the Northern Hemisphere (20–50°N) oceans, where historical aerosol increases have been largest. We find similarities in the overall radiative forcing from ACIs in the two models, but this belies fundamental underlying differences. The radiative forcing from increases in LWP is weaker in UPCAM, whereas the forcing from increases in Nd is larger. Surprisingly, the weaker LWP increase is not due to a weaker increase in LWP in raining clouds, but a combination of weaker increase in LWP in nonraining clouds and a smaller fraction of raining clouds in UPCAM. The implication is that as global modeling moves toward finer than storm-resolving grids, nuanced model validation of ACI statistics conditioned on the existence of precipitation and good observational constraints on the baseline probability of precipitation will become key for tighter constraints and better conceptual understanding. ©2020. The Authors.
英文关键词	aerosol-cloud interaction; climate change; clouds; GCM; multiscale model
语种	英语
scopus关键词	Aerosols; Atmospheric radiation; Aerosol-cloud interaction; Cloud droplet number concentrations; Cloud liquid water path; Cloud resolving model; Community atmosphere model; Conceptual understanding; Horizontal resolution; Northern Hemispheres; Climate models; climate forcing; climate modeling; cloud droplet; cloud microphysics; concentration (composition); historical record; Northern Hemisphere; parameterization
来源期刊	Journal of Advances in Modeling Earth Systems
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/156588
作者单位	Department of Earth System Science, University of California, Irvine, CA, United States; Lawrence Livermore National Laboratory, Livermore, CA, United States; Department of Atmospheric Sciences, University of Washington, Seattle, WA, United States
推荐引用方式 GB/T 7714	Terai C.R.,Pritchard M.S.,Blossey P.,et al. The Impact of Resolving Subkilometer Processes on Aerosol-Cloud Interactions of Low-Level Clouds in Global Model Simulations[J],2020,12(11).
APA	Terai C.R.,Pritchard M.S.,Blossey P.,&Bretherton C.S..(2020).The Impact of Resolving Subkilometer Processes on Aerosol-Cloud Interactions of Low-Level Clouds in Global Model Simulations.Journal of Advances in Modeling Earth Systems,12(11).
MLA	Terai C.R.,et al."The Impact of Resolving Subkilometer Processes on Aerosol-Cloud Interactions of Low-Level Clouds in Global Model Simulations".Journal of Advances in Modeling Earth Systems 12.11(2020).