气候变化领域集成服务门户(CCPortal): Which Orographic Scales Matter Most for Medium-Range Forecast Skill in the Northern Hemisphere Winter?

CCPortal

DOI	10.1029/2019MS001894
	Which Orographic Scales Matter Most for Medium-Range Forecast Skill in the Northern Hemisphere Winter?
	Kanehama T.; Sandu I.; Beljaars A.; van Niekerk A.; Lott F.
发表日期	2019
ISSN	19422466
起始页码	3893
结束页码	3910
卷号	11 期号:12
英文摘要	It is generally accepted that increased horizontal resolution improves the representation of atmospheric circulation in global weather and climate models. Understanding which processes contribute toward this improvement can help to focus future model development efforts. In this study, a set of 10-day global weather forecasts, performed with different atmospheric and orographic resolutions ranging from 180 to 9 km, are used to examine the impacts of resolving increasingly smaller orographic scales on the forecast skill of the Northern Hemisphere winter circulation. These experiments aim to answer two main questions: What is the relative contribution from increases in atmospheric versus orographic resolution to the overall improvement in the Northern Hemisphere winter medium-range forecast skill obtained when increasing the horizontal resolution? and How do different orographic scales affect different scales of the atmospheric flow? For experiments in which the subgrid-scale orography parametrizations are turned off, increases in orographic resolution are responsible for almost all of the increase in skill within the troposphere. In the stratosphere, higher atmospheric resolution also contributes to skill improvements, likely due to a better representation of gravity wave propagation and breaking. All scales of orography considered here are found to be important for the obtained changes in the circulation and appear to rapidly affect all considered scales of the flow. In experiments in which the subgrid-scale orography parametrizations are turned on, the benefits of increasing the horizontal resolution decrease, but do not entirely disappear, suggesting that these parametrizations are not perfect substitutes for the unresolved orography. ©2019. The Authors.
英文关键词	effective resolution; gravity wave drag; orographic drag; parametrized processes
语种	英语
scopus关键词	Atmospheric movements; Climate models; Drag; Gravity waves; Meteorology; Wave propagation; Atmospheric circulation; Effective resolutions; Gravity wave drag; Horizontal resolution; Medium range forecast; Northern Hemispheres; Relative contribution; Weather and climate models; Weather forecasting; atmospheric circulation; drag; gravity wave; Northern Hemisphere; orography; parameterization; wave propagation
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/156814
作者单位	Japan Meteorological Agency, Tokyo, Japan; European Centre for Medium-Range Weather Forecasts, Reading, United Kingdom; Met Office, Exeter, United Kingdom; Laboratoire de Météorologie Dynamique, Paris, France
推荐引用方式 GB/T 7714	Kanehama T.,Sandu I.,Beljaars A.,et al. Which Orographic Scales Matter Most for Medium-Range Forecast Skill in the Northern Hemisphere Winter?[J],2019,11(12).
APA	Kanehama T.,Sandu I.,Beljaars A.,van Niekerk A.,&Lott F..(2019).Which Orographic Scales Matter Most for Medium-Range Forecast Skill in the Northern Hemisphere Winter?.Journal of Advances in Modeling Earth Systems,11(12).
MLA	Kanehama T.,et al."Which Orographic Scales Matter Most for Medium-Range Forecast Skill in the Northern Hemisphere Winter?".Journal of Advances in Modeling Earth Systems 11.12(2019).