Dunes are not stationary because they move with the wind.
Sand dunes move down wind. A simple example: if the prevailing wind is from the west, the dunes will mainly move towards the east.
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wind
Yes. Dunce move in the direction of the current or wind.
wind and storms cause the dunes to move by moving around the individual sand grains when the dunes get too large the 15 mph winds will cause them to collapse and thus it has moved.
Short
Huge piles of sand are called sand dunes. Sand dunes typically form in deserts or coastal areas where there are strong winds that shape and move the sand into these large structures.
The wind causes movement
No way to tell, sand dunes move every time a wind springs up.
they dont have periods.
Dunes typically move in the direction of the prevailing wind. Sand particles are lifted and carried by the wind, causing the dune to migrate in the same direction as the wind.