Incipient bedforms in a bidirectional wind regime

  title={Incipient bedforms in a bidirectional wind regime},
  author={Cyril Gadal and Cl{\'e}ment Narteau and Sylvain Courrech du Pont and Olivier Rozier and Philippe Claudin},
  journal={Journal of Fluid Mechanics},
  pages={490 - 516}
Most terrestrial sand seas form at ‘horse’ latitudes, where the wind direction exhibits seasonal variation. Here, we extend the two-dimensional linear stability analysis of a flat sand bed associated with a unidirectional wind to the three-dimensional case in order to account for multidirectional wind regimes. Focusing on the simplest case of bidirectional flow regimes, we show that the transition from transverse to oblique or longitudinal patterns is controlled by the transport ratio and the… 

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