Carbon-cutting pledges from 146 nations for a universal climate rescue pact leave the "door open" to capping global warming below the danger threshold, the United Nations said Friday, a month ahead of crunch talks in Paris.
But even if these 10-to-15 year plans are fulfilled, humanity will have used up three-quarters of its carbon "budget" by 2030 and must slash greenhouse gas output even more to avoid devastating climate impacts, the UN's Climate Change Secretariat warned.
"An unprecedented world-wide effort is under way to combat climate change, building confidence that nations can cost-effectively meet their stated objective of keeping a global temperature rise to under 2 C," it said in an assessment of the country pledges.
"The national contributions are a game changer, and distance us from the worst," said French Foreign Minister Laurent Fabius, who will host the year-end climate talks.
At the same time, "much greater emissions reductions efforts... will be required" to meet the two degrees Celsius (3.6 degrees Fahrenheit) target endorsed by the UN 195-nation climate body, it said.
The longer we wait, the harder and more expensive it will become to cut back the fossil fuel emissions that drive climate change. The Secretariat's 66-page review comes exactly one month before the November 30 to December 11 meeting in the French capital tasked with finalising a historic global pact.