China has already surpassed the United States as the world's largest carbon polluter, the authors of a California study said Tuesday.
"Our best forecast has Chinas CO2 (carbon dioxide) emissions correctly surpassing the United States in 2006 rather than 2020 as previously anticipated," said the study by researchers at the University of California.
The report, written by economic professors Maximilian Aufhammer of UC Berkeley and Richard Carson of UC San Diego, is to be published next month in the Journal of Environmental Economics and Management.
Researchers compiled information about the use of fossil fuels in various Chinese provinces and forecast an 11 percent annual growth of carbon emissions from 2004 to 2010.
Previous estimates had set the growth rate at 2.5 to five percent.
The spike in air pollution by China has largely cancelled out efforts by other countries' attempts to reduce greenhouse greenhouse gas emmissions in accordance with the Kyoto Protocol, the authors said.
