3.1 Wind Ripples or Sand Dunes

Yet another simple CA rules make famous desert scenery. Beautiful ripples are developed 
in PC from any initial conditions. Basic rules (Nishimori & Ouchi,1993) are as follows:
1) Salutation: sand grains jumped over far sites depend on its height.
2) Creep: sand grains move to neighbor sites in order to reduce the surface ruggedness.
The process is iterated on all grids under various conditions.

Fig. 8: Wind ripples are developing left to right.

Fig. 9: Some interesting features of wind ripples in PC sim.