“Climate change is the greatest challenge of our time,” said Thomas F. Stocker, co-chairman of the Intergovernmental Panel on Climate Change, the United Nations-sponsored group of scientists that produced the report. “In short, it threatens our planet, our only home.” 
 
 The panel, in issuing its most definitive assessment yet of the risks of human-caused warming, hoped to give impetus to international negotiations toward a new climate treaty, which have languished in recent years in a swamp of technical and political disputes. The panel warns that continued emissions of greenhouse gases will cause further warming and changes in all aspects of the climate system. "Our assessment of the science finds that the atmosphere and ocean have warmed, the amount of snow and ice has diminished, the global mean sea level has risen and that concentrations of greenhouse gases have increased," said Qin Dahe, co-chair of IPCC working group one, who produced the report. That is an issue because this week, scientists from around the world have gathered in Stockholm for a meeting of a U.N. panel on climate change, and they will probably issue a report saying it is "extremely likely" _ which they define in footnotes as 95 percent certain _ that humans are mostly to blame for temperatures that have climbed since 1951. The new report finds a 95 to 100 percent chance that most of the warming of recent decades is human-caused, up from the 90 to 100 percent chance cited in the last report, in 2007.
– The UN's climate change panel for the first time charted the upper limit of acceptable global carbon emissions today—and we're already halfway to it. Based on an internationally agreed upon goal of keeping temperatures within 3.6 degrees Fahrenheit of their pre-industrial levels, humanity can only allow gas from 1 trillion tons of burned carbon to enter the atmosphere, the Intergovernmental Panel on Climate Change said in its report, according to the New York Times. We're on pace to hit that ceiling in 2040. The much-anticipated report was released this morning following a furious night of editing, but the substance of it hasn't changed much since a draft was released in August. The report also presents what, according to the BBC, is considered the most comprehensive statement on how climate change works, concluding with 95% certainty that human activity "has been the dominant cause" of the warming trend. That, the AP points out, is as certain as scientists are that cigarettes kill you, and more certain than they are that vitamins improve your health.