Cut back on soot, methane to slow warming: study

January 12, 2012

There are simple, inexpensive ways to cut back on two major pollutants -- soot and methane -- and taking action now could slow climate change for years to come, international scientists said Thursday.

When it comes to fending off global warming, the focus often is on harmful carbon emissions from in and car engines that linger in the atmosphere for many decades, said the study in Science.

But given the lack of comprehensive global action and mounting resistance from countries whose economies rely on cheap fuel, targeting two shorter-term pollutants could offer significant results over the coming decades, it said.

"Ultimately, we have to deal with CO2, but in the short term, dealing with these pollutants is more doable, and it brings fast benefits," said lead author Drew Shindell, a researcher at the NASA Goddard Institute for Space Studies and Columbia University's Earth Institute.

Soot, also known as , is a byproduct of burning wood, dung, coal and other fuels. It causes lung and heart disease in people, warms the air by absorbing sun radiation, and can shift .

Ways to cut back include building more efficient cookstoves, installing more filters on diesel vehicles, taking the worst polluting vehicles off the road and banning the practice of burning farmland, the study said.

Methane, which is the flammable part of natural gas and also results from decay and digestion, is a like C02 but is more potent.

Nations could update wastewater treatment plants, limit emissions from farm manure, drain more often, capture gas that escapes from and oil and gas facilities and reduce leaks from long-distance pipelines.

It should cost less than $250 to stop the emission of one metric ton of methane, but the benefits would range from $700 to $5,000, the article said.

Soot costs were harder to estimate but "the bulk of the measures could probably be implemented with costs substantially less than the benefits given the large valuation of the health impacts," it said.

If their 14 recommendations -- whittled from a potential field of 400 existing pollution control measures -- are followed, global warming could be reduced by about half a degree Centigrade (0.9 Fahrenheit) by 2050, the study said.

Between 700,000 and 4.7 million premature deaths could be averted and annual crop yields could rise by 30 million to 135 million metric tons.

Most of the lives saved would likely be in Bangladesh, Nepal and India where soot levels are high.

Ozone and farming benefits would likely center on hot places such as Iran, Pakistan and Jordan as well as southern Asia and the Sahel region of Africa.

The projections were made using computer models devised by US space agency NASA and the Max Planck Institute for Meteorology in Hamburg, Germany.

"The scientific case for fast action on these so-called 'short-lived climate forcers' has been steadily built over more than a decade, and this study provides further focused and compelling analysis of the likely benefits at the national and regional level," said Achim Steiner, executive director of the Nairobi-based United Nations Environment Program.

The research team included the Stockholm Environment Institute, Harvard School of Public Health, Scripps Institute of Oceanography, the Asian Institute of Technology in Bangkok, the US Environmental Protection Agency and the Joint Research Centre of the European Commission.

Explore further: Curb soot and smog to keep Earth cool, says UN

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2.2 / 5 (10) Jan 12, 2012
Since the preponderance of EVIDENCE suggests that the observed warming (and cooling) over the past is not and cannot be due to trace CO2, CH4, NOx, HFCs, SF6, etc GH gases this is just another "the sky is falling" release to keep pork barrel grant, i.e. tax, money flowing.

Soot though is a warming and health issue but the contribution in nebulous. Burning CH4, i.e. natural gas, does not produce soot so let the fraking continue!
1 / 5 (5) Jan 12, 2012
The simplest prevence of global warming and oil wars would be the implementation of cold fusion.
3 / 5 (2) Jan 12, 2012
I can hardly wait until someone invents a reliable cheap way of recycling cow farts. That would be worth a trip to the countryside.
3 / 5 (4) Jan 12, 2012
Burning CH4, i.e. natural gas, does not produce soot so let the fraking continue!

Amen. Using natural gas instead of coal to produce electricity also cuts the amount of CO2 per kwh produced more than in half. (Comparing combined cycle (natural) gas fueled plants to even the best coal burning steam plants.)

The price of natural gas is dropping in the US due to "oversupply" which really means that the electric utilities haven't caught up to the fracking production. Of course, some of this gas will go into replacing oil heating furnaces as what economists call a virtuous cycle keeps going. (Lower prices for a good (in this case natural gas) result in its replacing other goods (foreign oil) and the increased demand for the first good causes production of it to increase. Producers become more efficient and prices drop further. We all win.)
5 / 5 (1) Jan 12, 2012
parsec - over 80% of the methane cows produce comes out in belches. Capturing the tail emmissions has been done.
3.3 / 5 (4) Jan 13, 2012
Stop eating beef and you solve the majority of cow methane release without any technology. We have all read the ratio of tons of grain to produce a single ton of meat. We would also regain vast tracts of land for other use.

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