Rise In Greenhouse Gas Emissions

Annual carbon dioxide emissions from worldwide burning of fossil fuels reached a record high of 31.6 billion metric tons in 2011, according to preliminary estimates announced in late May by the International Energy Agency (IEA). The 2011 releases are up 3.2%, or 1.0 billion metric tons, over 2010’s CO₂ emissions, IEA says.

The country contributing most to this increase was China, the world’s largest emitter of CO₂, IEA says. China’s CO₂ emissions in 2011 were up 9.3%, or 720 million metric tons, from 2010.

This jump was primarily a result of increased burning of coal in China. But the rise would have been higher if China had not cut the amount of CO₂ emitted per unit of its gross domestic product—a measure called carbon intensity—by 15% between 2005 and 2011, IEA reports.

“What China has done over such a short period of time to improve energy efficiency and deploy clean energy is already paying major dividends to the global environment,” says Fatih Birol, IEA’s chief economist.

The U.S., the world’s second-largest emitter, saw its CO₂ releases from the burning of fossil fuels drop 92 million metric tons, or 1.7%, from 2010, IEA says. The decrease is primarily the result of a switch from coal to natural gas for power generation and a mild winter, which diminished energy demand for heating.

Since 2006, U.S. emissions have fallen by 7.7%, or 430 million metric tons, the organization says. The five-year reduction is the largest anywhere in the world, IEA says. It is due to improvements in transportation efficiency, higher oil prices, and the economic downturn, IEA says.