African dust storms huge, but how do they form?
The dust that fueled this storm in the central Nigerian town of Maradi came from the Sahara, the world's largest desert. Scientists believe that such storms, which can extend up to three miles into the atmosphere, result from a huge temperature gradient over the African continent. Photo courtesy of Tristan Clements.
Dust storms over Africa can be as large as the continential U.S. They travel for thousands of miles.
Dust storms over Africa have been studied for decades. More recently, scientists have learned that dust storms are powerful meteorological events. For example, they might suppress hurricanes.
Earth & Sky spoke to meteorologist Jason Dunion of NOAA’s Hurricane Research Division about how these African dust storms form.
Jason Dunion: One thing that we’ve learned over time is that there’s a huge temperature gradient over Africa, where you have this lush, tropical environment to the south, and this very hot desert to the north. And that actually helps to create some of these dust storms which can be the size of the continental U.S.
The dust itself comes from the biggest desert in the world, the Sahara. Dunion told Earth & Sky that these dust storms can extend up to 5 kilometers – about 3 miles – into the atmosphere.
Jason Dunion: You might not even know that they’re passing overhead, except that you might see some dust filtering out the sky line. In fact, in south Florida, here in Miami, we’ll usually get a few dust storms every year that actually make it all the way across the Atlantic, so they’ll travel for thousands of miles. So, it’s really a large phenomenon that can cover great distances, and it’s very large in scale.
Our thanks today to NASA: explore, discover, understand. We’re Block and Byrd for Earth & Sky.
Our thanks to:
Jason Dunion
Meteorologist
Atlantic Oceanographic and Meteorological Laboratory
Hurricane Research Division, NOAA
Miami, FL
Photo courtesy of Emanuele Nicastro.
Additional Teacher Resources
NOAA: Dust Storms
This website provides color images of dust storm events.
NOAA: Access of NOAA Satellite Data for Educators
This slide presentation shows how satellite data can be used in the classroom to study a variety of subjects, including dust storms, the hydrologic cycle, rainfall and flooding. Use http://www.osei.noaa.gov/nsta/nstaNS.html for any browser other than Explorer.
