NASA MODIS Image of the Day: July 21, 2009 – Cloud Vortices and Glory off Guadelupe Island, Mexico
Clouds cover the Pacific Ocean in this image, captured by the MODIS on the Terra satellite on July 5, 2009.
The small island you see is Guadalupe Island, which is located off the coast of Mexico’s Baja Peninsula.
The clouds south of the island are shaped like vortices. Turbulence, caused by the wind passing over the island, is what is creating these pronounced eddies in the clouds. This pattern is called a vortex “street”. The second interesting feature of this image is the narrow, faint reddish coloring in that can be seen to the left of Guadelupe Island in the clouds. This phenomenon is called a glory, which is often produced when light at the observer’s anti-solar point falls on a cloud deck below. What is the anti-solar point? If you had been standing on this satellite as it orbited the Earth, looking down at the cloud deck below you, the sun would have been directly behind you – 180 degrees from your line of sight. Ice and water particles in the cloud bend the light and reveal all its colors. Often, when a glory is seen from an airplane, viewers will see the shadow of the airplane in the center of the glory.
