Desert Dust Devil

Desert Dust Devil is an original illustration set in Atacama Interior, Chile. It lies in the tropics, where the climate is cold desert — arid, with freezing winters.

A tapered rotating column of dust rises from the ground, clearly connected to it, with a small circular skirt of lifted sand at the base. The dust forms hard-edged spiral bands rather than a soft haze. Scattered stones lie on a bare basin floor under a clear sky.

Why does a dust devil spin up out of a clear calm sky?

Dust devils need intense surface heating and clear calm air — the ground warms far faster than the air above, and a rising bubble of hot air starts to spin as it goes. They are a fair-weather phenomenon, the opposite of a storm. A basin floor this bare, this stony, under a cloudless sky at altitude, is one of the driest kinds of place on the planet.

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