Dust plays role in warmer global temps - Study
A decrease in airborne dust and volcanic emissions has contributed to
warming the North Atlantic Ocean in the past three decades, a study
showed Thursday.
About 70 percent of the Atlantic's warming since 1980, at an average
per-decade rate of a half-degree Fahrenheit (a quarter-degree Celsius),
was due to less dust blown from African dust storms or to volcanic
eruptions, scientists wrote in the journal Science.
"Volcanoes and dust storms are really important if you want to
understand (climatic) changes over long periods of time," said the
study's lead author Amato Evan, a researcher with the University of
Wisconsin-Madison.
He said airborne particles producing warmer temperatures can also
help cause hurricanes, which thrive on warm water.
Evan and his colleagues had previously shown that African dust and
other airborne particles can reduce hurricane activity by allowing less
sunlight to reach the water and thus cool the sea surface.
Years with low dust activity, such as 2004 and 2005 - a
record-breaking storm year - have been associated with more frequent
storms, the researchers noted. During their study, the researchers used
satellite data of dust and other particles along with existing climate
models to calculate how much of the Atlantic warming of the past 26
years was due to changes in tropical volcanic activity.
Major such volcanic eruptions that dimmed sunlight were Mexico's El
Chichon in 1982 and Mount Pinatubo in the Philippines in 1991.
Although volcanoes are unpredictable by nature, Evan said newer
climate models should at least include dust storms as a factor to
predict ocean temperature changes accurately.
WASHINGTON, AFP |