The dune skeleton model is a reduced model to describe the formation processand dynamics of characteristic types of dunes emerging under unidirectionalsteady wind. Using this model, we study the dependency of the morphodynamics oftransverse dunes on the initial random perturbations and the lateral fieldsize. It was found that i) an increase of the lateral field size destabilizesthe transverse dune to cause deformation of a barchan, ii) the initial randomperturbations decay with time by the power function until a certain time;thereafter, the dune shapes change into three phases according to the amount ofsand and sand diffusion coefficient, iii) the duration time, until thetransverse dune is broken, increases exponentially with increasing the amountof sand and sand diffusion coefficient. Moreover, under the condition withoutthe sand supply from windward ground, the destabilization of transverse dune inthis model qualitatively corresponds to the subaqueous dunes in water tankexperiments.
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