2 December 2012 Last updated at 13:00 ET
By Mark Kinver Environment reporter, BBC News
The concentration of CO2 is continue to rise, despite global efforts to curb future increases
It is increasingly unlikely that global warming will be kept below an increase of 2C (3.6F) above pre-industrial levels, a study suggests.
Data show that global CO2 emissions in 2012 hit 35.6bn tonnes, a 2.6% increase from 2011 and 58% above 1990 levels.
The researchers say that emissions are the largest contributor to future climate change and a strong indicator of potential future warming.
The findings have been published in the journal Nature Climate Change.
Meanwhile, the data has been published in the journal Earth System Science Data Discussions.
Many low-lying nations have used the UN conference, which is currently under way in Doha, to call for a threshold temperature rise less than 2C, arguing that even a 2C rise will jeopardise their future.
“These latest figures come amidst climate talks in Doha, but with emissions continuing to grow, it’s as if no-one is listening to the scientific community,” said Corinne Le Quere, director of the Tyndall Centre for Climate Change Research at the University of East Anglia. .…(more).