Fringing Coral Reef, Red Sea
The Sudanese coast of the Red Sea is a well-known destination for diving due to clear water and abundance of coral reefs (or shia’ab in Arabic). Reefs are formed primarily from precipitation of calcium carbonate by corals. (In addition to its commonly used meaning, precipitation can also describe how something dissolved in a solution becomes “undissolved” through chemical or biological processes.) Massive reef structures are built over thousands of years of succeeding generations of coral. In the Red Sea, fringing reefs form on shallow shelves of less than 50 meters depth along the coastline. This astronaut photograph illustrates the intricate morphology of the reef system located along the coast between Port Sudan to the northwest and the Tokar River delta to the southeast.
Close to shore, fringing reefs border the coastline. Farther offshore grows a larger, more complicated barrier reef structure. Different parts of the reef structure show up as variable shades of light blue. Deeper water channels (darker blue) define the boundaries for individual reefs within the greater barrier reef system. Such a complex pattern of reefs may translate into greater ecosystem diversity because of the wide variety of local reef environments.