Global CO2 emissions from fossil-fuel combustion reached a record high of 31.6 gigatonnes (Gt) in 2011, according to preliminary estimates from the International Energy Agency (IEA). This represents an increase of 1.0 Gt on 2010, or 3.2%. Coal accounted for 45% of total energy-related CO2 emissions in 2011, followed by oil (35%) and natural gas (20%).
The “450 Scenario” of the IEA’s World Energy Outlook 2011, which sets out an energy pathway consistent with a 50% chance of limiting the increase in the average global temperature to 2 °C, requires CO2 emissions to peak at 32.6 Gt no later than 2017, i.e. just 1.0 Gt above 2011 levels.
The 450 Scenario sees a decoupling of CO2 emissions from global GDP, but much still needs to be done to reach that goal as the rate of growth in CO2 emissions in 2011 exceeded that of global GDP, the IEA noted.
The new data provide further evidence that the door to a 2 °C trajectory is about to close.—IEA Chief Economist Fatih Birol
In 2011, a 6.1% increase in CO2 emissions in countries outside the OECD was only partly offset by a 0.6% reduction in emissions inside the OECD. China made the largest contribution to the global increase, with its emissions rising by 720 million tonnes (Mt), or 9.3%, primarily due to higher coal consumption. However, China’s carbon intensity—the amount of CO2 emitted per unit of GDP—fell by 15% between 2005 and 2011. Had these gains not been made, China’s CO2 emissions in 2011 would have been higher by 1.5 Gt, the IEA said.
India’s emissions rose by 140 Mt, or 8.7%, moving it ahead of Russia to become the fourth largest emitter behind China, the United States, and the European Union. Despite these increases, per-capita CO2 emissions in China and India still remain just 63% and 15% of the OECD average respectively.
CO2 emissions in the United States in 2011 fell by 92 Mt, or 1.7%, primarily due to ongoing switching from coal to natural gas in power generation and an exceptionally mild winter, which reduced the demand for space heating. US emissions have now fallen by 430 Mt (7.7%) since 2006, the largest reduction of all countries or regions.
This development has arisen from lower oil use in the transport sector (linked to efficiency improvements, higher oil prices and the economic downturn which has cut vehicle miles travelled) and a substantial shift from coal to gas in the power sector. CO2 emissions in the EU in 2011 were lower by 69 Mt, or 1.9%, as sluggish economic growth cut industrial production and a relatively warm winter reduced heating needs. By contrast, Japan’s emissions increased by 28 Mt, or 2.4%, as a result of a substantial increase in the use of fossil fuels in power generation post-Fukushima.