Black
carbon pollution emerges as major player in global warming
Soot
from biomass burning and diesel exhaust has 60 percent of the effect of
carbon dioxide on warming but mitigation offers immediate
benefits
Black carbon, a form of particulate air pollution most often
produced from biomass burning, cooking with solid fuels and diesel
exhaust, has a warming effect in the atmosphere three to four times
greater than prevailing estimates, according to scientists in an upcoming
review article in the journal Nature
Geoscience.
Scripps Institution of Oceanography at UC San Diego atmospheric
scientist V. Ramanathan and University of
Iowa chemical
engineer Greg Carmichael, said that soot and other forms of black carbon
could have as much as 60 percent of the current global warming effect of
carbon dioxide, more than that of any greenhouse gas besides CO2. The
researchers also noted, however, that mitigation would have immediate
societal benefits in addition to the long term effect of reducing Between
25 and 35 percent of black carbon in the global atmosphere comes from
China and
India, emitted from the burning
of wood and cow dung in household cooking and through the use of coal to
heat homes. Countries in Europe and
elsewhere that rely heavily on diesel fuel for transportation also
contribute large amounts. greenhouse gas emissions.
Elimination of black carbon, a contributor to global warming and a
public health hazard, offers a nearly instant return on investment, the
researchers said. Black carbon particles only remain airborne for weeks at
most compared to carbon dioxide, which remains in the atmosphere for more
than a century. In addition, technology that could substantially reduce
black carbon emissions already exists in the form of commercially
available products.
Carmichael said he hopes
that the paper’s presentation of the immediacy of the benefits will make
it easier to generate political and regulatory momentum toward reduction
of black carbon emissions.
“It offers a chance to get better traction for implementing
strategies for reducing black carbon,” he
said.
The National Science Foundation, the National Oceanic and
Atmospheric Administration and the National Aeronautics and Space
Administration funded the review.
Scripps
Institution of Oceanography: scripps.ucsd.edu
Scripps
News: scrippsnews.ucsd.edu
Contact: Rob
Monroe, Mario Aguilera
scrippsnews@ucsd.edu
858-534-3624
University
of California - San Diego
