Posted on March 8th, 2008 by admin

A dust storm bigger than Spain raged over the Atlantic a thousand miles 0ff West Africa last February 26. NASA satellite captured the event (right). Since the early 1970s more and more such storms have been spawned by drought in the Sahel region south of the Sahara. Satellites have recorded many of these African tempests, but the size and power of this monster left scientists agog. Riding air currents, one part of the storm blanketed the coast of Portugal and Spain; another part headed west toward the Americas.

Dust storms have long blown over the Atlantic. Aboard H.M.S. Beagle near the Cape Verde Islands in 1832, Charles Darwin recognized one storm’s origin. “The dust falls in such quantities as to dirty everything on board,” he wrote. “We may feel sure that it all comes from Africa.”

Today an army of researchers study the storms and their fallout. Many roll off Africa during summer, and several scientists are investigating whether they affect hurricane formation.

Much of the dust crossing the Atlantic falls in the southeast U.S., some as far west as New Mexico. A major depot is the Caribbean, where about a billion tons a year is dumped. There, some biologists believe, the dust causes stress and disease among coral reefs. Garriet Smith of the University of South Carolina has detected in the dust a fungus, Aspergillus, that kills soft corals such as sea fans. Yet when the same earthy essence of Africa drifts into South America; the phosphate it carries fertilizes the Amazon’s nutrient-poor soil.

Tags: africa dust, Disease, dust causes stress and disease, dust crossing the Atlantic, dust storm, nutrients ride airborne soil