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DOI	10.1073/pnas.2024105118
	Direct validation of dune instability theory
	Lü P.; Narteau C.; Dong Z.; Claudin P.; Rodriguez S.; An Z.; Fernandez-Cascales L.; Gadal C.; Du Pont S.C.
发表日期	2021
ISSN	00278424
卷号	118 期号:17
英文摘要	Modern dune fields are valuable sources of information for the large-scale analysis of terrestrial and planetary environments and atmospheres, but their study relies on understanding the small-scale dynamics that constantly generate new dunes and reshape older ones. Here, we designed a landscape-scale experiment at the edge of the Gobi desert, China, to quantify the development of incipient dunes under the natural action of winds. High-resolution topographic data documenting 42 mo of bedform dynamics are examined to provide a spectral analysis of dune pattern formation. We identified two successive phases in the process of dune growth, from the initial flat sand bed to a meter-high periodic pattern. We focus on the initial phase, when the linear regime of dune instability applies, and measure the growth rate of dunes of different wavelengths. We identify the existence of a maximum growth rate, which readily explains the mechanism by which dunes select their size, leading to the prevalence of a 15-m wavelength pattern. We quantitatively compare our experimental results with the prediction of the dune instability theory using transport and flow parameters independently measured in the field. The remarkable agreement between theory and observations demonstrates that the linear regime of dune growth is permanently expressed on low-amplitude bed topography, before larger regular patterns and slip faces eventually emerge. Our experiment underpins existing theoretical models for the early development of eolian dunes, which can now be used to provide reliable insights into atmospheric and surface processes on Earth and other planetary bodies. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Dune; Instability; Sediment transport; Size selection; Surface winds
语种	英语
scopus关键词	article; body patterning; China; desert; growth rate; prediction; prevalence; quantitative analysis; sediment transport; spectroscopy; topography
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
来源机构	中国科学院西北生态环境资源研究院
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/179733
作者单位	School of Geography and Tourism, Shaanxi Normal University, Xi’an, Shaanxi, 710119, China; Université de Paris, Institut de physique du Globe de Paris, CNRS, Paris, F-75005, France; Physique et Mécanique des Milieux Hétérogènes, CNRS, Ecole Supérieure de Physique et de Chimie Industrielles de la Ville de Paris, Paris Science & Lettres Research University, Sorbonne Université, Université de Paris, Paris, 75005, France; Northwest Institute of Eco-Environment and Resources, Lanzhou, Gansu Province, 730000, China; Laboratoire Matière et Système Complexes, Université de Paris, CNRS, Paris Cedex 13, 75205, France
推荐引用方式 GB/T 7714	Lü P.,Narteau C.,Dong Z.,et al. Direct validation of dune instability theory[J]. 中国科学院西北生态环境资源研究院,2021,118(17).
APA	Lü P..,Narteau C..,Dong Z..,Claudin P..,Rodriguez S..,...&Du Pont S.C..(2021).Direct validation of dune instability theory.Proceedings of the National Academy of Sciences of the United States of America,118(17).
MLA	Lü P.,et al."Direct validation of dune instability theory".Proceedings of the National Academy of Sciences of the United States of America 118.17(2021).