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Soot solution: New stoves?

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Are there any short-term solutions to climate change? One potentially quick fix being bandied about in India is the replacement of old cooking stoves that produce Earth-warming, lung-clogging black carbon (a.k.a. soot).

Soot accounts for 18 percent of greenhouse gas emissions, second only to carbon-dioxide (CO2), which accounts for 40 percent of the emissions blamed for global warming, according to today's New York Times. Scientists including Veerabhadran Ramanathan, an atmospheric physicist at the Scripps Institution of Oceanography in San Diego, are promoting solar-cookers as a quick fix to the soot problem while more complex technologies are developed to reduce the CO2 emissions, the Times reports.

"It is clear to any person who cares about climate change that this will have a huge impact on the global environment," Ramanathan told the newspaper. "In terms of climate change we’re driving fast toward a cliff, and this could buy us time."

ScientificAmerican.comreported last week on Ramanathan's effort to bring cleaner-burning stoves to 8,000 Indian households as part of our slideshow of 10 important atmospheric experiments. Similar efforts are ongoing in China, where innovators are also trying to clean up the air using biogas — fueling their stoves with decomposed human and animal waste instead of timber.

Cooking stoves are responsible for most of the soot in Asia and Africa (in the U.S., filters and scrubbers have slashed the amount of black carbon, the Times reports). Soot irritates the eyes, nasal passages and lungs of people who breathe it in, and has also been linked to cancer. It contributes to global warming by absorbing the sun's rays and heating whatever it touches; Ramanathan, as we note in this August 2007 piece, sent unmanned drones over India to measure the extent to which the brown soot cloud over the country was trapping sunlight. He found that it was responsible for 50 percent of the climate change there.

A bill introduced in the House last month by Rep. Jay Inslee (D-WA) would allocate federal monies to developing nations to buy new, cleaner cooking stoves.

Image by angelic_shrek via Flickr