Africa to the Amazon… To Scientific American
What the journey of a handful of dust tells us about our fragile planet
February 15, 2012
WASHINGTON, D.C. — The February 2012 issue of Scientific American features a story highlighting the research of University of Miami Rosenstiel School of Marine & Atmospheric Science Professor Emeritus, Dr. Joseph M. Prospero. The article “Swept From Africa to the Amazon,” by Jeffrey Bartholet touches on the process by which African dust is carried over much of the southern and eastern U.S. every summer.
Prospero, who has long been lauded as the “grandfather” of dust studies, has been publishing papers since the 1960’s and 1970’s suggesting a massive transport of African dust across the Atlantic to the Americas.
“African dust is carried over much of the southern ad eastern U.S. every summer and is responsible for 75-80 percent of the dust that falls over Florida. When it rains in Miami, and local residents clean a residue of reddish particles from their vehicles, they are wiping away a long-distance delivery from Africa. Walk across the islands of the Bahamas or the Florida Keys, and you will be hiking on African soil,” writes Bartholet.
Dust traveling over darker areas, like the oceans, cools the planet because it reflects some light that would otherwise be absorbed on the surface. Yet dust traveling over light colored areas like ice and sand tends to have a warming effect because it usually absorbs more light than the Earth’s surface.
“Dust is different from other aerosols because dust in the atmosphere-unlike man-made pollution-is dependent on climate itself,” Prospero says. “If climate change affects wind velocity and rainfall, it can have an immense impact. Dust is extremely sensitive to small changes in wind and rain. It’s the ultimate feedback loop.”
About the University of Miami’s Rosenstiel School
The University of Miami is the largest private research institution in the southeastern United States. The University’s mission is to provide quality education, attract and retain outstanding students, support the faculty and their research, and build an endowment for University initiatives. Founded in the 1940’s, the Rosenstiel School of Marine & Atmospheric Science has grown into one of the world’s premier marine and atmospheric research institutions. Offering dynamic interdisciplinary academics, the Rosenstiel School is dedicated to helping communities to better understand the planet, participating in the establishment of environmental policies, and aiding in the improvement of society and quality of life. For more information, please visit www.rsmas.miami.edu.