Cutting soot emissions from diesel engines and other sources could be the fastest, and most economical way to slow global warming, a US scientist has said.
Mark Z. Jacobson, Ph.D. says 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.
He cited concerns that continued melting of sea ice above the Arctic Circle would be a tipping point for the Earth's climate, a point of no return.
That's because the ice, which reflects sunlight and heat back into space, would give way to darker water that absorbs heat and exacerbates warming, he said.
Jacobson says that his calculations indicate that controlling soot could reduce warming above parts of the Arctic Circle by almost 3 degrees Fahrenheit within 15 years, virtually erasing all of the warming that has occurred in the Arctic during the last 100 years.
"No other measure could have such an immediate effect," said Jacobson, who is with Stanford University.
"Soot emissions are second only to carbon dioxide (CO2) in promoting global warming, but its effects have been underestimated in previous climate models.
"Soot emissions account for about 17 percent of global warming, more than greenhouse gases like methane.
"Soot's contribution, however, could be reduced by 90 percent in 5-10 years with aggressive national and international policies," he added.
The good news is that decreasing soot could have a rapid effect, Jacobson said. Unlike carbon dioxide, which remains in the atmosphere for years, soot disappears within a few weeks, so that there is no long-term reservoir with a continuing warming effect.
The study was presented at the 242nd National Meeting and Exposition of the American Chemical Society (ACS).