African dust can rip potential hurricanes apart
High in our atmosphere, wind carries rivers of tiny dust particles across continents and oceans. Here, you see a massive dust cloud coming out of Africa, beginning its travels across the Atlantic Ocean. (NASA image)
Scientists have observed that when potential hurricanes mix with African dust, the hurricanes weaken.
That’s according to meteorologist Jason Dunion with NOAA’s Hurricane Research Division. Dunion said that every year, about 60 so-called “tropical waves” push off of Africa.
These weather systems are the “seedlings” for hurricanes in the Atlantic. Only about one in 10 develops into a named storm. Using satellite records, Dunion found that heavy dust storm activity coincided with lulls in hurricanes.
Jason Dunion: And when a storm passes through an area where we have these, what we call Saharan air layers, or Saharan dust storms, there tends to be a very dry environment. And you can cut the moisture in the environment down by about 50 percent so that it becomes extremely dry, which can significantly limit how a storm is going to develop.
Wind also plays a role.
Jason Dunion: You see the winds will pick up dramatically, as much as 50 miles per hour, and that can act to rip the storms apart. So, what was a fairly tranquil tropical environment, when you get these Saharan dust storms to pass through, can become quite hostile for hurricane development, and can really change things pretty dramatically.
Dunion also said scientists are making slow progress in their understanding of hurricanes and ability to forecast them. Saharan dust storms may provide a missing piece of the puzzle.
Our thanks today to NASA : explore, discover, understand.
Our thanks to:
Jason Dunion
Meteorologist
Atlantic Oceanographic and Meteorological Laboratory
Hurricane Research Division
NOAA
Miami, FL
Additional Teacher Resources
NOAA: Tiny Dust Specks Could Have Big Effect on Hurricanes
Scientists are finding that Saharan Dust Storms containing tiny specks of dust are linked to suppressed hurricane activity in the Atlantic. This article provides information on this topic as well as satellite images of dust from space.
NASA: Did Dust Bust the 2006 Hurricane Season Forecasts?
This article provides information on a NASA study that suggests that tiny dust particles may have foiled forecasts that the 2006 hurricane season would be another active one. The article includes images and graphs.
