MIAMI, Florida -- Small dust particles from sand storms in the African Sahara that are making their way across the Atlantic Ocean toward the Caribbean and South Florida this week could signal fewer hurricanes during the 2012 Hurricane Season.
NOAA researchers
are finding that Saharan
dust storms containing tiny specks of dust are linked to suppressed
hurricane activity in the Atlantic. Because the dust particles are so small -- often less than 0.002
mm across -- they can remain aloft for days as they ride global
rivers of air. Larger sand grains don't get airborne as often
or for as long, but they can be pushed along the ground by the
wind or washed away by water erosion. Dust clouds cross the Atlantic Ocean and reach the Caribbean
and the Americas in about 5 to 7 days.
Jason Dunion,
a hurricane researcher at the NOAA Atlantic Oceanographic and Meteorological
Laboratory's Hurricane Research
Division in Miami, Florida, and his colleagues at the University of
Wisconsin-Madison, studied the past 25 years of satellite data prior to 2006. They
found that during times of intense hurricane activity, the large clouds
of dust that periodically blow westward from the Saharan Desert are
relatively scarce. In years when there were fewer hurricanes, the dust
storms were stronger and tended to spread over much of the Atlantic
and Caribbean Sea.
"The
research conducted by Dunion and his colleagues is improving our understanding
of hurricanes and what affects their behavior," said retired Navy
Vice Adm. Conrad Lautenbacher,
Ph.D., undersecretary of commerce for oceans and atmosphere and NOAA
administrator. "This is another example of how NOAA's research
provides value to society. This work will provide another data point
used to make better forecasts and warnings, which translates into saving
lives and protecting property."
"This
research is still in its infancy, but the results of this most recent
study are very encouraging," Dunion said. It represents the first
long-term analysis of the relationship between Saharan dust storms and
hurricanes and supports our previous hypotheses that these dust storms
tend to suppress hurricane formation."
In 2002,
Dunion developed a technique for detecting the large dust clouds using
special infrared imagery from the NOAA GOES satellites. Since then,
Dunion and his colleagues have been looking at the large dust clouds
and their possible effect on hurricanes.
Image above: Animation of a 2001 dust cloud crossing the Atlantic Ocean. Credit: NASA
Information Sources: NOAA / NASA