气候变化领域集成服务门户(CCPortal): Improvement of Drag Coefficient Calculation Under Near-Neutral Conditions in Light Winds Over land

CCPortal

DOI	10.1029/2020JD033472
	Improvement of Drag Coefficient Calculation Under Near-Neutral Conditions in Light Winds Over land
	Liu C.; Li Y.; Gao Z.; Zhang H.; Wu T.; Lu Y.; Zhang X.
发表日期	2020
ISSN	2169897X
卷号	125 期号:24
英文摘要	By analyzing the data collected over a rice paddy field in China, the occurrence of large drag coefficient in light winds (U ≤ 1ms−1) under near-neutral conditions (−0.1 ≤ z/L ≤ 0.1) is analyzed in this study. It is found that, with the use of either vector- or scalar-averaged wind speed, the drag coefficient under near-neutral conditions (CDN) always increases with the decrease of wind speed. Such behavior of CDN cannot be interpreted by the change of aerodynamic roughness length z0 because it would need to be enlarged by an order of magnitude. While in light winds, the nonlocal transport, which is caused by large-scale eddies and overlooked by traditional Monin-Obukhov Similarity theory, is found to be the main cause of increased CDN. At last, a fixing term related to nonlocal effects is proposed based on our observation, and its applicability is verified with two AmeriFlux observation sites with a landscape of forest and savanna, respectively. © 2020. American Geophysical Union. All Rights Reserved.
英文关键词	drag coefficient; land surface; light winds; near-neutral
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/185572
作者单位	School of Atmospheric Sciences, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China; Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing, China; State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China; Department of Atmospheric Science, School of Physics, Peking University, Beijing, China; Beijing Climate Center, China Meteorological Administration, Beijing, China; Chinese Academy of Meteorological Sciences, China Meteorological Administration, Beijing, China
推荐引用方式 GB/T 7714	Liu C.,Li Y.,Gao Z.,et al. Improvement of Drag Coefficient Calculation Under Near-Neutral Conditions in Light Winds Over land[J],2020,125(24).
APA	Liu C..,Li Y..,Gao Z..,Zhang H..,Wu T..,...&Zhang X..(2020).Improvement of Drag Coefficient Calculation Under Near-Neutral Conditions in Light Winds Over land.Journal of Geophysical Research: Atmospheres,125(24).
MLA	Liu C.,et al."Improvement of Drag Coefficient Calculation Under Near-Neutral Conditions in Light Winds Over land".Journal of Geophysical Research: Atmospheres 125.24(2020).