Clouds like a Dragon!
A dragon in the clouds. Click for a larger version. Credit: Jeff Schmaltz MODIS Land Rapid Response Team, NASA GSFC
NASA’s MODIS web site captures some intriguing images from the Earth; this 1 is 1 of my recent favorites through the TERRA satellite.
The caption through the MODIS site (you are able to get diverse sizes of this image), explore it too they have lots of great stuff:
Creating a striking design which looks a bit like a serpent swimming through clouds, curling patterns of eddies are formed as air flows close to and over the island of Tristan de Cunha inside the South Atlantic. This image was captured by MODIS on the Terra satellite on July 14, 2010.
The island can be witnessed as a small circle of green at the far left of the image, at the tip of a dark blue triangle of ocean. To the southeast a string of ocean-blue circles are surrounded by rings of bright white cloud, illustrating the symmetric and swirling pattern of airflow on the leeward side on the island. These spiraling cloud patterns, caused when prevailing ocean winds encounter an island, are known as von Karman vortices or “vortex streets”.
Just like the swirls that will be observed within the wake of airplane wings, these vortex streets result through the separation of flow around an immobile body – in this case the island – causing neighboring areas of flow to circulate in alternating clockwise and counter-clockwise directions.
House to about 275 folks, Tristan de Cunha is considered to be the most remote inhabited island from the world, lying 2,816 km (1,750 mi) from South Africa, the nearest land, and 3,360 km (1,510 mi) from South America. The landmass is very little, measuring 6 m (10 miles) wide, with a total area of 38 sq. m (98 sq. km). Even so, the terrain is incredibly steep. Queen Mary’s Peak, an active volcano, rises to 2,062 m (6,765 feet) above sea level.
