Improvements in air quality will lead to a decrease in aerosols, small particles in the atmosphere that act as a brake on the impact of greenhouse gases. As the effect of aerosols lessen, searing temperatures could follow.
"This new way of integrating the aerosol, greenhouse gas and biosphere effects changes the picture from one where climate change most likely is a fairly tolerable thing to one where there is a fairly high risk of change sooner, and to a higher degree," said Professor Meinrat Andreae.
The Intergovernmental Panel on Climate Change (IPCC) predicts a rise in global temperatures from a doubling of carbon dioxide could be in the range of 1.5-4.5 degrees Celsius by the end of the century. But according to calculations by Andreae and his team, the upper figure could be as high as 6 degrees.
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"The actual true force of the greenhouse gases has been masked by the effects of the aerosols. They put a brake on warming and we don't really know how strong that brake is," said Andreae, who reported his findings in the journal Nature.
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