The formation and evolution of aeolian dune fields under unidirectional wind

In this paper, we quantitatively simulated an aeolian dune field of hundreds of square kilometers over several hundred years based on a comprehensive scale-coupled model (CSCDUNE). Furthermore we analyzed the variation of dune shape, scale, and the probability density distribution of dune size. Results show that the threshold thickness of sand supply increases with increasing sand diameter but decreases with increasing wind speed, and wind speed and sand diameter have some influence on dune morphology. The probability density distribution of dune size and that of lateral length of transverse dunes obey a normal distribution and a negative exponential distribution, respectively. Finally, a fitting formula, describing the variation of dune height with time, wind speed, sand diameter and the thickness of sand supply, is provided.

► The evolution of dune fields with hundreds of kilometers is quantitatively simulated.
► Rules of dune morphology changing with some key parameters are investigated.
► A fitting formula describing dune height varying with time is provided.
► Fitting formulas describing the PDF of dune height and lateral length are provided.
► The threshold thickness of sand supply determining dune morphology is presented.