LONDON — The United States is off the hook: last year China overtook the U.S. to become the world's biggest emitter of carbon dioxide. "The tall tree attracts the wind," and from now on China will be the main target of the criticism that used to be directed at the U.S. for refusing to accept binding limits on its greenhouse gas emissions.
What's particularly striking is the speed with which China has passed the U.S. In 2005 its CO2 emissions were two percent lower than those of the U.S.; in 2006 they were eight percent higher. Yet China only has four times the population of the U.S., and the average Chinese is nothing like a quarter as rich as the average American. In fact, the vast majority of Chinese don't even own cars. So why does China produce so much CO2?
One reason is cement. The pace of building in China is so intense that the country produces 44 percent of the world's cement (the U.S. produces 4 percent), and cement production is a major source of greenhouse gases. The main culprit, however, is coal, which accounts for 70 percent of China's energy consumption.