Curbing coal emissions alone might avert climate danger, say researchers

Oil and gas seen to have lesser effect

An ongoing rise in atmospheric carbon dioxide from burning of fossil fuels might be kept below harmful levels if emissions from coal are phased out within the next few decades, say researchers. They say that less plentiful oil and gas should be used sparingly as well, but that far greater supplies of coal mean that it must be the main target of reductions. Their study appears in the journal Global Biogeochemical Cycles.

The burning of fossil fuels accounts for about 80 percent of the rise of atmospheric CO₂ since the pre-industrial era, to its current level of 385 parts per million. However, while there are huge amounts of coal left, predictions about when and how oil and gas production might start running out have proved controversial, and this has made it difficult to anticipate future emissions. To better understand how the emissions might change in the future, climatologist Pushker Kharecha and director James Hansen of NASA Goddard Institute for Space Studies—a member of Columbia University's Earth Institute--considered a wide range of scenarios.