Each of these swirling clouds is the result of a meteorological phenomenon known as a von Karman
vortex. These vortices appeared over Alexander Selkirk Island in the southern Pacific Ocean.
Rising precipitously from the surrounding waters, the islands highest point is nearly a mile
(1.6 km) above sea level. As wind-driven clouds encounter this obstacle, they flow around it to
form large, spinning eddies.
This image was acquired by
Landsat 7s Enhanced Thematic Mapper plus
(ETM+) sensor on September 15, 1999. This is a false-color composite image made using shortwave
infrared, infrared, and near-infrared wavelengths.
Image provided by the
USGS EROS Data Center Satellite Systems
Branch.