气候变化领域集成服务门户(CCPortal): Climate models permit convection at much coarser resolutions than previously considered

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DOI	10.1175/JCLI-D-19-0286.1
	Climate models permit convection at much coarser resolutions than previously considered
	Vergara-Temprado J.; Ban N.; Panosetti D.; Schlemmer L.; Schär C.
发表日期	2020
ISSN	0894-8755
起始页码	1915
结束页码	1933
卷号	33 期号:5
英文摘要	The "gray zone" of convection is defined as the range of horizontal grid-space resolutions at which convective processes are partially but not fully resolved explicitly by the model dynamics (typically estimated from a few kilometers to a few hundred meters). The representation of convection at these scales is challenging, as both parameterizing convective processes or relying on the model dynamics to resolve them might cause systematic model biases. Here, a regional climate model over a large European domain is used to study model biases when either using parameterizations of deep and shallow convection or representing convection explicitly. For this purpose, year-long simulations at horizontal resolutions between 50- and 2.2-km grid spacing are performed and evaluated with datasets of precipitation, surface temperature, and top-of-theatmosphere radiation over Europe. While simulations with parameterized convection seem more favorable than using explicit convection at around 50-km resolution, at higher resolutions (grid spacing # 25 km) models tend to perform similarly or even better for certain model skills when deep convection is turned off. At these finer scales, the representation of deep convection has a larger effect in model performance than changes in resolution when looking at hourly precipitation statistics and the representation of the diurnal cycle, especially over nonorographic regions. The shortwave net radiative balance at the top of the atmosphere is the variable most strongly affected by resolution changes, due to the better representation of cloud dynamical processes at higher resolutions. These results suggest that an explicit representation of convection may be beneficial in representing some aspects of climate over Europe at much coarser resolutions than previously thought, thereby reducing some of the uncertainties derived from parameterizing deep convection. © 2020 American Meteorological Society.
英文关键词	Natural convection; Coarser resolution; Explicit representation; Horizontal resolution; Regional climate modeling; Shallow convection; Surface temperatures; Systematic modeling; Top of the atmospheres; Climate models; atmospheric convection; climate modeling; data set; diurnal variation; precipitation assessment; regional climate; Europe
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/171433
作者单位	Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, Switzerland; Deutscher Wetterdienst Offenbach and Hans Ertel Centre for Weather Research, Goethe University Frankfurt, Frankfurt, Germany; Department OfAtmospheric and Cryosphere Sciences, University of Innsbruck, Innsbruck, Austria
推荐引用方式 GB/T 7714	Vergara-Temprado J.,Ban N.,Panosetti D.,et al. Climate models permit convection at much coarser resolutions than previously considered[J],2020,33(5).
APA	Vergara-Temprado J.,Ban N.,Panosetti D.,Schlemmer L.,&Schär C..(2020).Climate models permit convection at much coarser resolutions than previously considered.Journal of Climate,33(5).
MLA	Vergara-Temprado J.,et al."Climate models permit convection at much coarser resolutions than previously considered".Journal of Climate 33.5(2020).