Geomorphology: Solitary wave behaviour of sand dunes

@article{Schwmmle2003GeomorphologySW,
  title={Geomorphology: Solitary wave behaviour of sand dunes},
  author={Veit Schw{\"a}mmle and Hans J{\"u}rgen Herrmann},
  journal={Nature},
  year={2003},
  volume={426},
  pages={619-620}
}
Barchan sand dunes are highly mobile, crescent-shaped dunes that occur in areas where sand is sparse and the wind is unidirectional. Here we show mathematically how two such loose-grained dunes are able to pass through one another while still preserving their shape. The crucial parameters for this solitary-wave behaviour, which is consistent with field observations, are the heights of the two colliding dunes. 

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