Air flows like water in the atmosphere with invisible currents and waves. On April 9, 2014, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this view that evokes fluid-like movement in the atmosphere. Ship wave clouds fan out behind the Crozet Islands over the southern Indian Ocean looking exactly like the ripples behind a rock in a stream or the waves behind a boat moving through calm water.
The clouds take this shape in response to the flow of air in the atmosphere. Air was flowing smoothly over the ocean, and the clouds around the islands are proof of the unimpeded flow. These marine clouds are a solid bank and even in texture with little to disturb their uniformity. When the smooth-flowing air hit the Crozet Islands, it split around their rocky mass. The disturbance set up a wave pattern in the classic “v” shape we see behind similar disturbances in water. The turbulent air shaped the clouds into the wave pattern seen here.
The Crozet Islands are in the southern Indian Ocean roughly halfway between Antarctica and Madagascar. The islands are part of France’s southern and Antarctic lands. A designated conservation area, they are home to seals, penguins, and sea birds. The islands are uninhabited except for a small research station.
Acquired November 23, 2009, this true-color image shows wave clouds formed by air currents passing over the South Sandwich Islands. The islands anchor the V-shaped clouds that spread out toward the east.