Greenhouse gas emissions increased by a record amount last year, to the highest carbon output in history, putting hopes of holding global warming to safe levels all but out of reach, according to unpublished estimates from the International Energy Agency.
The shock rise means the goal of preventing a temperature rise of more than 2 degrees Celsius - which scientists say is the threshold for potentially "dangerous climate change" - is likely to be just "a nice Utopia", according to Fatih Birol, chief economist of the IEA. It also shows the most serious global recession for 80 years has had only a minimal effect on emissions, contrary to some predictions.
Last year, a record 30.6 gigatonnes of carbon dioxide poured into the atmosphere, mainly from burning fossil fuel - a rise of 1.6Gt on 2009, according to estimates from the IEA regarded as the gold standard for emissions data.
"I am very worried. This is the worst news on emissions," Birol told the Guardian. "It is becoming extremely challenging to remain below 2 degrees. The prospect is getting bleaker. That is what the numbers say."
Professor Lord Stern of the London School of Economics, the author of the influential Stern Report into the economics of climate change for the Treasury in 2006, warned that if the pattern continued, the results would be dire. "These figures indicate that [emissions] are now close to being back on a 'business as usual' path. According to the [Intergovernmental Panel on Climate Change's] projections, such a path ... would mean around a 50% chance of a rise in global average temperature of more than 4C by 2100," he said.