The Médano Blanco, or white dunes, are a popular recreational area about 250 miles south of Buenos Aires.
Its dune field extends from the white sand beaches of the South Atlantic to the fields of sunflowers and other lush landscape about 2 miles inland at its widest point.
The photo of the area to the right was taken on February 13, 2011, by a NASA astronaut orbiting aboard the International Space Station.
It shows the angular patterns of green and brown fields, irrigated with water from streams dammed behind the dunes. Médano Blanco is located not far from the windswept borderlands with Patagonia, one of the most blustery places on Earth.
Strong winds blow across the dunes from the west (bottom to top in this image) creating tall waves in the sand.
The crests of the waves can be seen oriented perpendicular to the prevailing wind. The winds are so constant that the Termas de Campo Spa erected a solid grove of trees on the south side of the resort to block them. The trees appear as a patch of very dark green in the enlarged view of the image.
Full story and image: NASA