气候变化领域集成服务门户(CCPortal): Origins of Turbulent Transport Dissimilarity Between Dust and Momentum in Semiarid Regions

CCPortal

DOI	10.1029/2019JD031247
	Origins of Turbulent Transport Dissimilarity Between Dust and Momentum in Semiarid Regions
	Fernandes R.; Dupont S.; Lamaud E.
发表日期	2020
ISSN	2169897X
卷号	125 期号:15
英文摘要	Turbulent transport of mineral dust away from erodible plots is usually assumed similar to the momentum transport. However, observations from the WIND-O-V (WIND erOsion in presence of sparse Vegetation's) 2017 field experiment over an isolated flat surface in Tunisia showed a dissimilar turbulent transport between dust and momentum. Here, the origin of this dissimilarity is explored from a numerical experiment using a detailed physically based erosion model based on a large-eddy simulation airflow model. Simulations support the findings of the WIND-O-V campaign, confirming the key role played by the dust emission intermittency to the transport dissimilarity with the momentum, this later one being more continuously absorbed at the surface. Simulations reveal that this dissimilarity diminishes with height as the intermittency of dust emission is progressively lost during the turbulent transport-mixing process. With wind intensity, the dissimilarity diminishes as well, with dust emissions becoming more spatially homogeneous, and thus less intermittent. Our simulations further highlight the additional role played by the fetch length limitation of the erodible plot to the turbulent transport dissimilarity. In presence of a short fetch, the dissimilarity between dust and momentum turbulent transports increases with height as the dust flux footprint integrates dust emission conditions from different surrounding surfaces. This latter process depends on the characteristics of the surrounded surfaces and is expected to be significant in semiarid regions. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	dust emission intermittency; dust suspension model; dust transport dissimilarity; fetch; large eddy simulations; semiarid erosion
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/185854
作者单位	INRAE, Bordeaux Sciences Agro, ISPA, Villenave d'Ornon, France
推荐引用方式 GB/T 7714	Fernandes R.,Dupont S.,Lamaud E.. Origins of Turbulent Transport Dissimilarity Between Dust and Momentum in Semiarid Regions[J],2020,125(15).
APA	Fernandes R.,Dupont S.,&Lamaud E..(2020).Origins of Turbulent Transport Dissimilarity Between Dust and Momentum in Semiarid Regions.Journal of Geophysical Research: Atmospheres,125(15).
MLA	Fernandes R.,et al."Origins of Turbulent Transport Dissimilarity Between Dust and Momentum in Semiarid Regions".Journal of Geophysical Research: Atmospheres 125.15(2020).