Elusive Opportunity

The Emissions Gap Report 2013 from the United Nations Environment Programme estimates that the effort to limit carbon dioxide emissions will fall 8 to 12 billion tons short of a goal set in 2010. The "window of opportunity" to prevent a 2 degree Celsius rise in global temperature is closing.

Update (November 6):  The World Meteorological Organization reports that the atmospheric carbon dioxide concentration averaged 393.1 ppm in 2012, a new record.  The increase from 2011 to 2012 was higher than the average increase over the previous ten years.

Update (November 15):  At the Warsaw climate talks, Japan announced a revised goal for reducing carbon dioxide emissions by 2020:  from 25 percent to 3.8 percent of 2005 levels due to the shutdown of their nuclear plants.

Update (November 25):  A study has found that US methane emissions have been underestimated. The revised estimate of 49 million tons for 2008 is 1.5 to 1.7 times as much as previous estimates.

Update (December 22, 2015):  A study says cold-season methane emissions from permafrost have been underestimated. Also, soil erosion in general increases carbon emissions.