Here’s an interesting suggestion for one thing we could do right away to slow down climate change for “only” $15 billion.

Weaning humanity from its fossil fuel habit will take decades, and it will take decades more for global warming to stop. But one simple measure could slow warming in some of Earth’s most sensitive regions, effective immediately — and it would cost just $15 billion.

That’s a rough price tag for providing clean stoves to the 500 million households that use open fires, fed by wood and animal dung and coal, to heat their homes and cook. Those fires produce one-quarter of all so-called “black carbon,” a sooty pollutant that’s adding to the planetary heat burden.

“We know how to cook without smoke,” said Veerabhadran Ramanathan, a University of California, San Diego climatographer. “A clean stove costs $30. Multiply that by 500 million households, and it’s only $15 billion. This is a solvable problem.”

After floating to the atmosphere, black carbon mixes with dust to form a solar heat-absorbing particulate layer. Raindrops form around the particles, trapping even more heat. Soot deposited by the rain heats up, too.

The climate dynamics of the black carbon process have been fully described only in the last decade, but scientists now say their short-term impact sometimes rivals that of carbon dioxide. As much as one-half of the 3.4 degree Fahrenheit rise in Arctic temperatures since 1890 is attributed to black carbon. By disrupting weather patterns, it may be responsible for weakening seasonal rains in South Asia and West Africa. And black carbon is also a major reason why Himalayan glaciers, which provide water to hundreds of millions of people, are vanishing.

UPDATE at 12/16/09 1:57:26 pm:

Here’s a video showing how the “clean stoves” work:

Youtube Video

(From StoveTeam International.)