Policies to stem the release of global greenhouse gas emissions have failed to slow the acceleration of such gases to dramatic levels at the start of the century, the United Nations’ top panel on climate change has said.
The Intergovernmental Panel on Climate Change report, the third in a series, says that emissions grew more quickly between 2000 and 2010 than in each of the three previous decades.
The report says that estimates of the economic costs of mitigation vary widely, with ambitious mitigation reducing consumption growth by about 0.06 percent points a year. But the underlying estimates do not account for the economic benefits of reduced climate change, the IPCC said.
It’s possible to limit the increase in global mean temperature to two degrees C above pre-industrial levels using a wide array of technologies and behavior changes, the report says. But to have a good chance of staying under this threshold, global GHG emissions must fall by 40-70 percent by mid-century, and near-zero by 2100, compared with 2010.
Humans might even be forced to remove carbon dioxide from the atmosphere to meet the temperature target, the IPCC said.
Update: An early version of this article ran due to an editing error. The article has now been updated.