Breeding and Solitary Wave Behavior of Dunes

TL;DR

This paper investigates the interactions of barchan dunes, revealing behaviors like crossing, coalescence, breeding, and budding, and models these phenomena to better understand dune dynamics and pattern formation.

Contribution

It introduces a model for dune interactions that captures complex behaviors such as crossing, coalescence, breeding, and budding, advancing understanding of dune pattern evolution.

Findings

Dunes can behave like solitary waves, crossing each other under certain conditions.

Interactions include coalescence, breeding, and budding, depending on dune size and conditions.

The study provides a framework for predicting dune behavior in natural environments.

Abstract

Beautiful dune patterns can be found in deserts and along coasts due to the instability of a plain sheet of sand under the action of the wind. Barchan dunes are highly mobile aeolian dunes found in areas of low sand availability and unidirectional wind fields. Up to now modelization mainly focussed on single dunes or dune patterns without regarding the mechanisms of dune interactions. We study the case when a small dune bumps into a bigger one. Recently Schwammle et al. and Katsuki et al. have shown that under certain circumstances dunes can behave like solitary waves. This means that they can ``cross'' each other which has been questioned by many researchers before. In other cases we observe coalescence, i.e. both dune merge into one, breeding, i.e. the creation of three baby dunes at the center and horns of a Barchan, or budding, i.e. the small dune, after ``crossing'' the big one, is unstable and splits into two new dunes.