Periodicity in fields of elongating dunes

Abstract

Dune fields are commonly associated with periodic patterns that are among the most recognizable landscapes on Earth and other planetary bodies. However, in zones of limited sediment supply, where periodic dunes elongate and align in the direction of the resultant sand flux, there has been no attempt to explain the emergence of such a regular pattern. Here, we show, by means of numerical simulations, that the elongation growth mechanism does not produce a pattern with a specific wavelength. Periodic elongating dunes appear to be a juxtaposition of individual structures, the arrangement of which is due to regular landforms at the border of the field acting as boundary conditions. This includes, among others, dune patterns resulting from bed instability, or the crestline reorganization induced by dune migration. The wavelength selection in fields of elongating dunes therefore reflects the interdependence of dune patterns over the course of their evolution.

arXiv comment7 pages, 4 figures

References in corpus (3)

• On the crescentic shape of barchan dune
• Incipient bedforms in a bidirectional wind regime
• 3D Dune Skeleton Model as a Coupled Dynamical System of 2D Cross-Sections

Cited by in corpus (6)

• Direct validation of dune instability theory
• Spatial and temporal development of incipient dunes
• Local Wind Regime Induced by Giant Linear Dunes: Comparison of ERA5-Land Reanalysis with Surface Measurements
• Coexistence of two dune growth mechanisms in a landscape-scale experiment
• Field evidence for the initiation of isolated aeolian sand patches
• From lab to landscape-scale experiments for the morphodynamics of sand dunes