May 8, 2007
TRANSCONTINENTAL
WILDFIRE EMISSIONS
MONITORED FROM SPACE
Using
data from the SCIAMACHY
instrument aboard ESA's environmental satellite Envisat, scientists
have
determined that the carbon monoxide hovering over Australia
during the wildfire
season largely originated from South American wildfires some 13,000
kilometers
away.
Using SCIAMACHY, Annemieke Gloudemans from SRON Netherlands Institute
for Space
Research and her colleagues at Utrecht University,
the Vrije
Universiteit Amsterdam and the Netherlands Meteorological Institute
(KNMI)
witnessed large quantities of released carbon monoxide (CO) above the
southern
continents. They also saw increased concentrations of carbon monoxide
above Central Australia,
a desert region that is not prone to
forest fires.
"Initially we
assumed that the wildfires in North
Australia were responsible for this. Yet when we
took a closer look at the transport of carbon monoxide, we had to
conclude that
the majority originated from fires in South
America.
Even one-third of the carbon monoxide enhancements above the fires in
North
Australia originated from South
America,"
Gloudemans said.
Knowledge about the
global distribution of carbon
monoxide is important because it affects air quality and climate.
SCIAMACHY is the
first satellite instrument that
can measure the global distribution of carbon monoxide with nearly
equal
sensitivity from the uppermost layer of the atmosphere down to the
Earth
surface where the carbon monoxide sources are located.
"SCIAMACHY allows us
to map the sources of
carbon monoxide and see where they are blown to," Gloudemans added.
"We did this for all of the continents in the southern hemisphere
– South America,
Australia
and Southern Africa
– for the years 2003 and
2004 and found surprising results.
"It has been known
for many years now that
carbon monoxide from forest fires can be transported over long
distances, but
one would expect that the plume would rapidly become more diffuse the
longer it
travels. So, it was very surprising to find that even over Australian
biomass-burning areas still up to 30% of the enhanced carbon monoxide
levels
from forest fires originate in South
America."
Forest fires in South America
produced much more carbon monoxide in 2004 than in 2003, Gloudemans
explained.
"These levels correlated to the amounts found over Australia for the same
periods, confirming that
the carbon monoxide levels over Australia
are severely influenced by South American forest fires."
Plumes of carbon
monoxide signal strong biomass
burning. Apart from the carbon monoxide detected by SCIAMACHY, numerous
other
compounds are emitted that have severe consequences for air quality and
climate.
Depending on the
aridity, much of Australia
is
prone to fires between October and March, and the direct consequences
for
humans and the environment are disastrous. The fire season in South
America,
often concentrated in Brazil,
Argentina,
Bolivia
and Venezuela,
lasts from July to December roughly and contributes up to 50% of the
enhanced
carbon monoxide levels in the atmosphere over Australia.
##
Contact:
Mariangela
D'Acunto
European
Space Agency
39-069-418-0856
Mariangela.DAcunto@esa.int
This text derived from:
http://www.esa.int/esaEO/SEMH7ZU681F_environment_0.html
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