Saturation Transients in Saltation and their Implications on Dunes Shapes 1
نویسندگان
چکیده
We present a model for dune formation that takes saturation transients in the saltation layer into account. We show that these transients introduce a characteristic length scale that is crucial for dune formation and the macroscopic shape of dunes, albeit determined by intrinsic properties of the saltation kinetics. Finally, we demonstrate that our model can explain the scale dependence of the shape of barchan dunes revealed in recent field measurements. Résumé – Nous présentons un modèle pour la formation de dunes qui incorpore des transients de saturation dans la couche de saltation et ansi sa dynamique. Nous montrons que ces transients introduisent une longeur characteristique qui est importante pour la formation de dunes, mais qui est basée sur des propriétés dynamiques intrinsèques de la kinétique de saltation. Finalement, nous montrons que notre modèle peut expliquer les différences de forme entre des dunes petites et grandes, ce qu’ont revelé de nouvell mesures.
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