BEIJING (AP) _ China has overtaken the United States as the world's top producer of carbon dioxide emissions _ the biggest man-made contributor to global warming _ based on the latest widely accepted energy consumption data, a Dutch research group says.
According to a report released Tuesday by the Netherlands Environmental Assessment Agency, China overtook the U.S. in emissions of CO2 by about 7.5 percent in 2006. While China was 2 percent below the United States in 2005, voracious coal consumption and increased cement production caused the numbers to rise rapidly, the group said.
``It's an expression of their fast industrial production activities and their fast development,'' Jos G.J. Olivier, the agency's senior scientist who compiled the figures, said Wednesday. The agency is independent but paid by the Dutch government to advise it on environmental policy.
The study said China, which relies on coal for two-thirds of its energy needs and makes 44 percent of the world's cement, produced 6.23 billion metric tons of carbon dioxide in 2006. In comparison, the U.S., which gets half its electricity from coal, produced 5.8 billion metric tons of CO2.
The group's analysis makes sense and had been predicted to happen by 2009 or 2010, said experts from the United Nations and the U.S. Energy Information Administration, and outside academics.
Bert Metz, a senior researcher at the Dutch agency and a leading expert on efforts to battle global warming, said the analysis was done using methods and data that ``are the best currently available.''
This means that ``Chinese contributions to global CO2 emissions are getting more important,'' Metz said in an e-mail to The Associated Press.
Telephone calls to China's State Environmental Protection Agency and the National Development and Reform Commission, the Cabinet-level economic planning agency, were not answered Wednesday.
Earlier figures indicated China would likely surpass the U.S. in greenhouse gas emissions as early as 2009, although other predictions said it could happen this year.
Chinese environmental officials have said that while total emissions are going up, they are still less than one quarter of those of the United States on a per capita basis. Because China's population of 1.3 billion people is more than four times that of the United States, China spews about 10,500 pounds of carbon dioxide per person, while in the United States it is nearly 42,500 pounds per person.
Olivier said there was not much chance China will now lose its lead.
``China's growth will saturate at some point,'' he said. But ``for now, we don't see a trend (toward) this saturation yet.''
Olivier said the research was based on data on fossil fuel consumption from BP PLC's Review of Energy 2007, compiled by the British oil company, and cement production data through 2006 published by the U.S. Geological Survey.
John Christensen, head of the U.N. Environment Program's Center on Energy, Climate and Sustainable Development in Denmark, said the figures did not come as a surprise.
``The Dutch agency referred to BP statistics, which is the standard reference tool. We have no reason to doubt that the numbers are right. We have no reason to doubt the methodology,'' Christensen said. ``It's been stated many times that China will overtake the U.S. in emissions.''
Other sources of carbon dioxide, such as deforestation and the flaring of gas in oil and gas production, are not included in the data. They also do not include methane from fuel production and agriculture and nitrous oxide from industry.
Fatih Birol, chief economist of the Paris-based International Energy Agency also said the findings were not surprising, given China's economic growth of more than 9 percent annually over the past 25 years.
His agency had estimated China would overtake the U.S. before 2010; in November it sharpened the forecast to 2007 or 2008.
But the issue isn't just current emissions, but carbon dioxide stuck in the atmosphere, where it lingers for about a century trapping heat below, said Jay Apt, a professor of engineering, business and public policy at Carnegie Mellon University in Pittsburgh.
Apt and a colleague calculated the share of carbon dioxide now in the atmosphere that can be attributed to each country and determined that the United States is responsible for 27 percent, European nations contributed 20 percent and China only 8 percent.
``The planet does not respond to emissions, the planet responds to the amount of carbon dioxide in the atmosphere,'' said Apt. ``It means the U.S. will have the lion's share of carbon dioxide in the atmosphere for the foreseeable future. In fact, even if China's exponential growth continues, China will not surpass the U.S. in the numbers of carbon dioxide atoms in the atmosphere, that is concentration, until at least 2050, which is too late to start anything.''
The International Energy Agency's Birol said the key message from the emission figures isn't who is No. 1, but the need to slow growth in CO2 emissions. ``The rest of the world with the help of China needs to find ways for China to reduce CO2 emissions,'' Birol said.
China has come under growing international pressure to take more forceful measures to curb releases of greenhouse gases.
This month, China unveiled its first national program to combat global warming with promises to rein in greenhouse gas production. While the program offered few new concrete targets for greenhouse gas emissions, it outlined steps the country would take to meet a previously announced goal of improving energy efficiency in 2010 by 20 percent over 2005's level.
Beijing also indicated an unwillingness to enforce mandatory emissions caps.
Ma Kai, the minister heading the National Development and Reform Commission, said economic development is a priority for China, but efforts would be made to raise awareness about global warming.
China signed the 1997 Kyoto Protocol, which caps the amount of carbon dioxide that can be emitted in industrialized countries. But because China is considered a developing country it is exempt from emission reductions _ a situation often cited by the Bush administration and Australia for not accepting the treaty.
Yang Ailun of Greenpeace China called on the country to take more steps to protect the environment. ``Due to the urgency of climate change, China has the responsibility to take immediate actions to reform its energy structure and curb its CO2 emissions,'' Yang said in a statement.
She noted that Western consumers use products made in China.
``All the West has done is export a great slice of its carbon footprint to China and make China the world's factory,'' she said. ``This trend has kept the price of projects in the West down, but led to a climate disaster in the long term.''