English: The Cape Verde Islands sit off of the west coast of North Africa, an area notorious for strong winds and shifting cloud cover. When roaring winds strike the rugged mountains of the islands, the wind hits the mountain faces and is pushed around them, creating swirling turbulence on the opposite (lee) side of the island. When clouds are present in the atmosphere, the turbulent patterns can be written as swirls and streaks in the clouds.

On March 2, 2018, the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite acquired a true-color image of the Cape Verde Islands and surrounding skies.

A number of complex swirling patterns to the southwest of the islands are the result of turbulent wind patterns. Splotchy banks of cloud, primarily marine stratocumulus clouds, add interest to the image.

It also appears that sunglint affects the image, especially in the lower left section of the image where a silvery sheen is apparent. Sunglint is an optical phenomenon that occurs when sunlight reflects off the surface of the ocean at the same angle that the satellite views the surface. Where the waters of the ocean are smooth, the sheen is mirror-like and silver in color. Where the water is rougher, the water appears dark. The abrupt demarcation between brightness and dark that lies on a generally northwest to southeast axis in the lower right of the image is likely the line between smooth ocean and rough seas.