Last year, global emissions of carbon dioxide (CO2) reached their highest level yet, according to preliminary estimates from the International Energy Agency. Setting the record, emissions from fossil fuel combustion peaked at 31.6 gigatons (Gt) in 2011, an increase of 1 Gt (or 3.2%) over the previous year.
China was the single largest contributor, releasing 9.3% more CO2 in 2011 than they had in previous years. Still, things could have been worse: at least China has been making an effort to improve energy efficiency and use cleaner energy, explained IEA Chief Economist Fatih Birol in a statement on the agency’s website. If it had not been for these efforts, the IEA estimates that China’s 2011 emissions would have been another 1.5 Gt higher.
The US showed the greatest improvement in emission levels, having managed to reduce their CO2 footprint by 7.7% since 2006, thanks to the move towards using natural gas instead of coal to generate power, and the milder winter putting less strain on furnaces and space heaters. The country still ranked second overall, followed by the European Union, India and Russia as the world’s third, fourth and fifth largest emitters.
According to the IEA’s World Energy Outlook 2011, global CO2 emissions need to peak no higher than 32.6 Gt by 2017, in order to keep the world’s temperature from rising more than 2 degrees Celsius. This allows for just another 1 Gt increase over 2011 levels if we’re to keep global warming within that 2 degree window.