pixability
time keeps on
It’s called an aeolian process, named for the Greek god Aeolus, the keeper of the winds. Wind lifts the smaller grains of sand and carries them, hopping across the surface like agitated fleas. As those grains bump along they disturb other grains, the smaller of which are also lifted and carried. The larger grains of sand may be too heavy to take to the air, but the bumping shifts them slightly causing the surface to form ripples that are generally perpendicular to the direction of the wind. The distance between the ripples corresponds to the distance the small grains of sand are carried by the wind before bumping down again.
Emergent obstacles…a pair of stones, for example…disrupt the laminar nature of the wind, generating turbulence in the form of an eddy. This radically reshapes the rippling, swirling the tumbling sand into the gentlest of topological forms: the curve.
The poet Li Po knew nothing of all that when he sat down, slightly intoxicated, and wrote:
By the North Gate, the wind blows full of sand,
Lonely from the beginning of time until now!
Trees fall, the grass goes yellow with autumn.
Science has its place. Art has its place. The wind pays no mind to either.
Blog photograph copyrighted to the photographer and used with permission by utata.org. All photographs used on utata.org are stored on flickr.com and are obtained via the flickr API. Text is copyrighted to the author, greg fallis and is used with permission by utata.org. Please see Show and Share Your Work
