What might cause a sand dune to become smaller

The sand dunes can become smaller by the direction of the wind, or they type of sand that is being blown into the dunes. If the wind is blowing in the same direction, they can degrade, but sand dunes don't really become smaller, they usually shift, And move or they change shape. It all depends on the wind, and the type of sand. There are four types of sand dunes, and all have different effects.

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