Recent scientific studies have found black carbon - a component of soot that comes from the burning of fossil fuels and plant materials - to be a key cause of climate change. Black carbon has a strong warming effect both in the atmosphere, and when it lands on snow, ice caps and glaciers, where it absorbs the sun's heat, reduces reflectivity and causes widespread and faster melting, causing sea level rise and other climate changes.

Black soot on glaciers contributes to melting.

Because black carbon remains in the atmosphere for only a few days - unlike other greenhouse gases, which may remain in the atmosphere for over a century - reducing black carbon emissions may be among the most effective near-term strategies for slowing global warming and avoiding some of the most imminent climate change tipping points. Decreasing black carbon emissions should be a relatively cheap way to significantly curb global warming. Replacing primitive cooking stoves with modern versions that emit far less soot could quickly end the problem. Controlling traffic in the Himalayan region should help ease the harm done by emissions from diesel engines. Yet the United Nations Framework Convention on Climate Change does not address the contribution of this important global warming pollutant.  link

Recent news: 

Sept. 1 2011: Reducing soot second most important factor in global warming. A new study of dust-like particles of soot in the air, now emerging as the second most important, but previously overlooked, factor in global warming, provides fresh evidence that reducing soot emissions from diesel engines and other sources could slow melting of sea ice in the Arctic faster and more economically than any other quick fix. Calculations indicate that controlling soot could reduce warming above parts of the Arctic Circle by almost 3 degrees Fahrenheit within 15 years which would virtually erase all of the warming that has occurred in the Arctic during the last 100 years. link

June 2011: Black carbon emissions 3 to 5 times greater than previously thought. 
New evidence shows that black carbon soot may be even more damaging to the Himalayan region of the world. Black carbon soot is a potent climate pollutant that is causing up to half the warming in the Arctic region, and also much of the warming in the Himalayan-Tibetan Plateau, two super critical ecosystems that are warming two to three times faster than the global average. The Tibetan Plateau, the planet's largest store of ice after the Arctic and Antarctic, is warming about three times the global average, with temperature increases of 0.3ºC or more per decade measured for the past half-century. link

Black Carbon comes from diesel engines, industrial smokestacks and residential cooking and heating stoves. Most black carbon that falls in the Arctic comes from North America, Europe and Asia. Because black carbon air pollution is also a leading cause of respiratory illness and death, controlling emissions will save lives and improve health around the world. In India alone, black carbon-laden indoor smoke is responsible for over 400,000 premature deaths annually, mostly of women and children. The U.S. and Europe must lead on this issue by committing to stricter standards at home for diesel engines and other sources of black carbon pollution, and by committing to increased financial and technological assistance to the developing world to reduce black carbon pollution from diesel, home cooking and heating and other sources. Norway's foreign minister said action on black carbon was even more urgent than that on CO2: "Even if we turn the rising curve of greenhouse gas emissions in the coming years, the reduction will not occur quickly enough to preserve the polar and alpine environments. We must address short lived climate pollutants such as black carbon."  link   (pictured A brick kiln spews soot in Kabul, Afghanistan.)

February 2011: A new report from the United Nations environment programme has concluded cutting the amount of soot we pour into the atmosphere, and emissions of methane from agriculture, would be one of the most powerful ways to tackle climate change. Preventing "black carbon", particles of soot from industry and cooking fires, from polluting the air would help to cut global warming by as much as 0.5C, and reduce warming in the Arctic by about two thirds by 2030. link

September 2010: NASA - does heating from black carbon increase cooling from clouds? Reducing black carbon may not be a silver bullet solution many thought according to a new study from NASA. It appears that the net warming effect is more complicated than previousley realized. The study concludes that in some climate model studies "the cooling effect due to cloud changes is strong enough to essentially cancel the warming direct effects". Due to its warming effect, reduction of soot could help cool climate. However, soot absorption  also affects cloud distribution, and clouds mostly cool the climate. link

May 2010: Research questions value of cutting black carbon as a global warming solution.  In recent years, enthusiasm for lowering global emissions of black carbon has increased. But new research published in the journal Geophysical Research Letters suggests that black carbon's contribution in the climate system is not so straightforward as once thought. While there is little doubt that the fine black particles released from diesel and biomass cook stoves warm the planet by sitting in the atmosphere and absorbing energy, they also affect cloud formation in ways that can create a cooling mechanism, the study says. link

December 2009: New research blames soot for Himalayan warming. Soot coming out from a car’s tailpipes, and not greenhouse gases, could take most of the blame for rapidly melting glaciers in the Himalayas, according to a study led by National Aeronautics and Space Administration. Scientists feared that the black carbon spewed out by industries and cars around the Himalayas might accelerate the melting of the glaciers, which could threaten freshwater resources in the region. William Lau, head of atmospheric sciences at NASA's Goddard Space Flight Center, said there are some parts in the Himalayas that are warming more than five times faster than the global rate. link

October 2009: Soot clouds pose threat to Himalayan glaciers. Glaciers in the Himalayas and the Tibetan plateau that feed the river systems of almost half the world's people are melting faster because of the effects of clouds of soot from diesel fumes and wood fires, according to scientists in India and China. "This is a huge problem which we are ignoring," said Professor Syed Hasnain of the Energy and Resources Institute (Teri) in Delhi. "We are finding concentrations of black carbon in the Himalayas in what are supposed to be pristine, untouched environments." Hasnain says India and China produce about a third of the world's black carbon, and both countries have been slow to act. "India is the worst. At least in China the state has moved to measure the problem. In Delhi no government agency has put any sensors on the ground. [Teri] is doing it by ourselves." Decreasing black carbon emissions should be a relatively cheap way to significantly curb global warming. Black carbon falls from the atmosphere after just a couple of weeks, and replacing primitive cooking stoves with modern versions that emit far less soot could quickly end the problem. Controlling traffic in the Himalayan region should help ease the harm done by emissions from diesel engines  link

April 2009. Black carbon may account for as much as half of Arctic warming.  
The nations of the Arctic Council, including the United States, met in Tromsø, Norway, where action to slow Arctic warming was a major focus. Backed by government ministers and scientists, Al Gore said that soot, also known as "black carbon", from engines, forest fires and partially burned fuel was collecting in the Arctic where it was creating a haze of pollution that absorbs sunlight and warms the air. It was also being deposited on snow, darkening its surface and reducing the snow's ability to reflect sunlight back into space. While the chief culprit in global warming is carbon dioxide, recent studies show that black carbon - microscopic airborne particles commonly known as soot - is also a big factor. Curbing black carbon is crucial for slowing Arctic and global warming, and for averting catastrophic tipping points such as the melting of sea ice and the Greenland ice sheet.
 
May 2009. In a surprise U-turn, Republican senator James Inhofe (who has called global warming "a hoax") has put forward a bill to review the dangers of black carbon to health and the environment. Soot was not even mentioned as a cause of global warming in the United Nations' report on climate science in 2007. But scientists now see the pollutant as the main cause of global warming after carbon dioxide, and say it may require even more urgent action because of the speed of which ice in the Arctic is disappearing. Whether Inhofe has changed his views is unclear, but his support for the black carbon bill met with astonishment from left and right. link
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New Jersey is one state showing concern for black carbon. Stopthesoot web site explains that diesel emissions contain more than 40 known and probable carcinogens, including fine particulate matter, commonly called soot. Every year, hundreds of New Jerseyans die prematurely and suffer asthma attacks or other debilitating respiratory illnesses from harmful diesel soot. The goal of the Diesel Risk Reduction Program is to reduce the amount of particulate matter emitted by diesel vehicles. Several initiatives including the Diesel Engine Reduction Act of 2005 and the 2007 Highway Rule are already moving big on-road vehicles, such as 18-wheelers, toward drastically lowered black carbon emissions. In fact, the EPA estimates that black carbon emissions will decline 42% from 2001 through 2020, largely because of the diesel rules.
                                 
Earthjustice site and video link explaining "soot" - here