Global emissions of CO2 will hit 43.7 billion tonnes in 2030, up from 25 billion tonnes in 2003, the Energy Information Administration said in its annual forecast.

By 2025 global CO2 emissions could hit 40.05 billion tonnes annually, up 0.03 percent from the forecast issued last year, said the EIA, the statistics arm of the Department of Energy. Last year's report did not look as far ahead as 2030.

Most scientists believe a build-up in greenhouse gases, such as CO2, is raising average temperatures around the world. Catastrophic changes have been predicted, such as heatwaves, stronger storms and melting icecaps that could raise sea levels by almost three feet (one meter) by 2100.

Humans cause much of the buildup of CO2 by burning fossil fuels such as oil, gas, and the most CO2-intensive fuel, coal. Coal burning, which is growing in China and India, and to a lesser extent in the United States, could overtake oil as the largest fuel source of CO2 emissions after 2015, the EIA said.

The forecast did not include potential effects of CO2 reduction plans, including the international pact known as the Kyoto Protocol, saying the long-term impact of such plans are not yet known.

The Kyoto pact, which went into force early last year, requires 35 rich countries to reduce greenhouse gas emissions to an annual average about 5 percent below their 1990 levels by 2008 to 2012. Countries signed on to the agreement have agreed to set tougher caps in the second phase of the plan, but no timetable has been set for agreeing on the goals.

President George W. Bush withdrew the United States from the Kyoto pact in 2001, saying the treaty would hurt the economy and unfairly leave rapidly developing nations without C02 restraints in its first phase.

DEVELOPING ASIA TO SURPASS NORTH AMERICA

The report said that in four years, CO2 emissions in rapidly developing countries in Asia, such as China and India, will surpass those from North America.

In 2003, CO2 emissions of 6.8 billion tonnes from North America were about 12 percent higher than those in developing Asia, a far more populous region, according to the EIA.

By 2010, that changes. Developing Asian countries will emit about 9.1 billion tonnes of CO2, surpassing North American emissions by about 21 percent, according to the EIA.

Emissions from North America should average 1.3 percent growth per year from 2003 to 2030 and hit 9.7 billion tonnes by 2030, the EIA said. In developing Asian countries, emissions should average 3.6 percent growth to reach 16 billion tonnes by 2030, the report said.

Total US emissions have risen by 15.8 percent from 1990 to 2004, the US Environmental Protection Agency has said.

In Russia and eastern Europe, which experienced an economic downturn late last century, CO2 emissions won't return to 1990 levels until after 2025, according to the EIA.