The chances of the world holding temperature rises to 2C – the level of global warming considered "safe" by scientists – appear to be fading fast with US scientists reporting the second-greatest annual rise in CO2 emissions in 2012.
Carbon dioxide levels measured at at Mauna Loa observatory in Hawaii jumped by 2.67 parts per million (ppm) in 2012 to 395ppm, said Pieter Tans, who leads the greenhouse gas measurement team for the US National Oceanic and Atmospheric Administration (NOAA). The record was an increase of 2.93ppm in 1998.
The jump comes as a study published in Science on Thursday looking at global surface temperatures for the past 1,500 years warned that "recent warming is unprecedented", prompting UN climate chief, Christiana Figueres, to say that "staggering global temps show urgent need to act. Rapid climate change must be countered with accelerated action."
Tans told the Associated Press the major factor was an increase in fossil fuel use. "It's just a testament to human influence being dominant", he said. "The prospects of keeping climate change below that [two-degree goal] are fading away."