⚙️ how
How do sand dunes migrate across deserts?
Quick Answer
Wind blows sand up the gentle side of a dune and grains avalanche down the steep side, slowly moving the dune forward.
The Full Story
Sand dunes move because wind transports sand grains up the windward slope until they pass the crest. Once the slope becomes too steep, the sand tumbles down the leeward side in small avalanches. This repeated process causes the entire dune to migrate, often at speeds from a few centimeters to several meters per year depending on wind strength and sand supply. Dune shape depends on wind direction, vegetation, and grain size, which is why barchan, transverse, and star dunes look different.
Key Facts
1.Dunes migrate by repeated sand avalanches
2.Some dunes move meters per year
3.Dune shape reflects wind and sand supply
YouTube Angle
Suggested video title for this topic:
"The slow crawl of a moving mountain of sand"
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