Black Carbon May Be Bigger Player In Loss Of Himalayan Glaciers Than Previously Thought

[hatrack]

The fact that glaciers in the Himalayan mountains are thinning is not disputed. However, few researchers have attempted to rigorously examine and quantify the causes. Lawrence Berkeley National Laboratory scientist Surabi Menon set out to isolate the impacts of the most commonly blamed culprit—greenhouse gases, such as carbon dioxide—from other particles in the air that may be causing the melting. Menon and her collaborators found that airborne black carbon aerosols, or soot, from India is a major contributor to the decline in snow and ice cover on the glaciers. “Our simulations showed greenhouse gases alone are not nearly enough to be responsible for the snow melt,” says Menon, a physicist and staff scientist in Berkeley Lab’s Environmental Energy Technologies Division. “Most of the change in snow and ice cover—about 90 percent—is from aerosols. Black carbon alone contributes at least 30 percent of this sum.”

Menon and her collaborators used two sets of aerosol inventories by Indian researchers to run their simulations; their results were published online in the journal Atmospheric Chemistry and Physics.

The actual contribution of black carbon, emitted largely as a result of burning fossil fuels and biomass, may be even higher than 30 percent because the inventories report less black carbon than what has been measured by observations at several stations in India. (However, these observations are too incomplete to be used in climate models.) “We may be underestimating the amount of black carbon by as much as a factor of four,” she says.

The findings are significant because they point to a simple way to make a swift impact on the snow melt. “Carbon dioxide stays in the atmosphere for 100 years, but black carbon doesn’t stay in the atmosphere for more than a few weeks, so the effects of controlling black carbon are much faster,” Menon says. “If you control black carbon now, you’re going to see an immediate effect.”

EDIT

http://newscenter.lbl.gov/feature-stories/2010/02/03/black-carbon-himalayan-glaciers/

[OKIsItJustMe]

1. See also

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=222046&mesg_id=222046
http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=230328&mesg_id=230360

[OKIsItJustMe]

2. World’s Pall of Black Carbon Can Be Eased With New Stoves

http://e360.yale.edu/content/feature.msp?id=2250

08 Mar 2010: Report

World’s Pall of Black Carbon Can Be Eased With New Stoves

Two billion people worldwide do their cooking on open fires, producing sooty pollution that shortens millions of lives and exacerbates global warming. If widely adopted, a new generation of inexpensive, durable cook stoves could go a long way toward alleviating this problem.

by jon r. luoma

With a single, concerted initiative, says Lakshman Guruswami, the world could save millions of people in poor nations from respiratory ailments and early death, while dealing a big blow to global warming — and all at a surprisingly small cost.

“If we could supply cheap, clean-burning cook stoves to the large portion of the world that burns biomass,” says Guruswami, a Sri Lankan-born professor of international law at the University of Colorado, “we could address a significant international public health problem, and at the same stroke cut a major source of warming.”



Sooty, indoor air pollution from open wood or other biomass fires has long been linked to health problems and deaths. More recently, scientists have been surprised to learn that black carbon — not only from biomass fires but from dirty diesel engines and other sources — is a far larger contributor to global warming than previously suspected: The dark particles absorb and retain heat close to the Earth’s surface that might otherwise be reflected.

Some two billion people around the world, Guruswami notes, do most or all of their cooking and heating with fires from simple biomass — dried dung, wood, brush, or crop residues. In India alone, the ratio is much higher — about three-fourths.

...