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Updated: Jul 16, 2026
06:55
Kinematic History of a Salient-recess Junction Explored through a Combined Approach of Field Data and Analog Sandbox Modeling
Published on: August 5, 2016
Minimal size of a barchan dune
E J R Parteli1, O Durán, H J Herrmann
1Institut für Computerphysik, ICP, Universität Stuttgart, Pfaffenwaldring 27, 70569 Stuttgart, Germany.
Summary
Barchan dune size and shape are determined by wind friction and surrounding sand flux, not just a constant distance. This explains coastal dune sizes and Martian dune scales.
Area of Science:
- Geomorphology
- Physics of granular materials
- Planetary science
Background:
- Barchan dunes are crescent-shaped, highly mobile dunes formed by unidirectional winds.
- Previous models suggested a constant flux fetch distance, failing to explain barchan dune protosizes on Earth and Mars.
Purpose of the Study:
- To investigate the factors controlling the size and shape of minimal barchan dunes.
- To reconcile theoretical models with observed barchan dune characteristics on Earth and Mars.
Main Methods:
- Three-dimensional numerical simulations of sand transport.
- Analysis of wind friction speed and inter-dune sand flux.
Main Results:
- Barchan dune size and shape are dependent on wind friction speed and the sand flux in the surrounding dune field.
- This model explains the common occurrence of decimeter-scale barchan dunes along coastlines.
- The rate of saltation on Mars is significantly higher than on Earth, crucial for determining Martian dune sizes.
Conclusions:
- The critical size of barchan dunes is not solely determined by a constant flux fetch distance.
- Wind friction and inter-dune sand flux are key parameters influencing barchan dune morphology.
- Understanding Martian saltation rates is essential for accurately modeling dune formation on Mars.
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