recent. New research reveals just how dramatic and far-reaching that
movement can be. These are not global warming effects, but they
behave in much the same way.
In 2000, a team from the U.S. Geological Survey’s Center for
Coastal Geology reported that several million tons of dust resulting
from droughts in Africa was being transported annually to the western
Atlantic Ocean, where it was reducing visibility in the Virgin Islands
and causing the temporary closing of airports. “Our hypothesis is that
some of the decline of the reefs in [the Caribbean] is linked to the
increase in dust transport,” the team said, adding that 1-inch grasshop-
pers from Africa had been blown to the windward islands in a 1989
dust storm. “If they can make it, think of all the other things that can
make it,” said Eugene A. Shinn, who led the team.
Shinn says that the biggest losses of Caribbean coral occurred in
1983 and 1987, which were also the years of the greatest dust move-
ment. Further, in the mid-1990s, an epidemic that killed sea fans in
the Caribbean was caused by a soil fungus. The fungus, Aspergillus,
was believed to have come from run-off caused by deforestation, but
there were also outbreaks on remote islands with no forests at all.
Two dust storms that occurred in the Gobi Desert in 1998, killing
twelve people in Xinjiang, China, crossed the Pacific Ocean in 5 days,
carried by the western winds that are typical for the northern mid-lati-
tudes. They came to ground between British Columbia and California
and created a small furor. Phenomena like this are described in dry sci-
entific papers that, in rare lapses, offer some clear prose. In a study pre-
pared by a virtual working group headed by Washington University in
St. Louis, “The Asian Dust Events of April 1998,” it is noted, “The most
noticeable impact of the dust [which arrived in North America on April
25, 1998] was the discoloration of the sky. Human observer reports and
digital photographs indicate that from April 25 onward, the normally
blue sky appeared milky white throughout the non-urban West Coast.”
In an effect similar to the Asian cloud, there was a marked 25 to 35
percent decrease in direct normal solar radiation measured in Oregon,
and high levels of particulate matter in California, Washington,
Oregon, and Nevada. In most affected states, health agencies issued air
pollution advisories.
90 Jim Motavalli