Global carbon dioxide emissions from burning fossil fuels will rise to a record 36 billion tonnes this year, a report by 49 researchers from 10 countries said, showing the failure of governments to rein in the main greenhouse gas blamed for global warming.
The report by the Global Carbon Project, which compiles data from research institutes worldwide each year, was published in the journal Earth Systems Data Discussions on Tuesday.
Its 2013 estimate represents a 2.1 percent gain versus 2012 and a 61 percent increase since 1990, the baseline year for the U.N.'s Kyoto Protocol, the only global agreement that places binding limits on national CO2 emission levels.
The report was published as officials from almost 200 nations are gathered in Warsaw, Poland, tasked with advancing U.N. negotiations on a new pact to curb emissions from all nations due to take effect from 2020.
"Governments ... need to agree how to reverse this trend. Emissions must fall substantially and rapidly if we are to limit global climate change to below 2 degrees Celsius," said the report's lead author, Corinne Le Quere of the Tyndall Centre for Climate Change Research at Britain's University of East Anglia, in a statement.
She was referring to a rise in the average global temperature from levels prior to the Industrial Revolution. U.N.-backed scientists have warned that a gain above 2 degrees will trigger extreme floods, droughts and storms.
The report shows that the rate of growth in global CO2 emissions is down slightly on the previous year's 2.2 percent increase but is only slightly lower than the average growth of 2.7 percent a year in the last 10 years.
Emissions are increasing because strong growth in coal consumption has outweighed any reductions from the rapid growth in renewable energy in recent years, according to Glen Peters, an author of the report based at CICERO, a climate research institute in Norway.
"While society is seeing many positive developments in renewable energy, this increased production capacity is not simply displacing coal consumption," Peters said in a separate statement.