Why does the word for desert carry a drop of water?
What looks like nitpicking actually opens a small door into how Chinese characters think.
The driest place on the map, and its name still carries a water radical — a small built-in contradiction, written right into the character.
Intuition says the stone-radical 砂 fits better: coarse, hard, the kind of thing you could chip straight off a cliff.
But 沙 leans toward something finer — grains worn down by water, then carried, then left behind. Which, when you stand in a desert, is exactly what the wind has been doing for centuries: sifting everything down to powder.