The good news is that such changes are possible and affordable, according to the report, which estimated that holding the rise in temperature over the next 30 years to less than 2 degrees Celsius (3.6 degrees Fahrenheit) would reduce the world's average annual GDP growth by only about 0.12 percent per year, or 3 percent by 2030.
The report was the third in a series issued by the United Nations' Intergovernmental Panel on Climate Change. It was compiled by scientists and agreed upon by officials from more than 120 countries, after four days of negotiations in Bangkok, Thailand.
"The strong message [from the report] is that it's possible to stabilize greenhouse gas emissions at the level where severe climatic change can be avoided," Swedish delegate Lars Nilsson told the Associated Press.
To do so, though, governments must take quick action, said Peter Lukey, a delegate from South Africa. "The message is: We have to do something now," he told the AP.
The first report in the series, released in February, found that carbon dioxide and other greenhouse gasses released by human activity were almost certainly causing most of the Earth's warming since 1950. The second report, released in April, found that global warming is already changing weather patterns around the world, and that hundreds of millions of people face possible droughts, floods and other ecological disasters should the warming continue. It predicted that global temperatures could rise as much as 11 degrees Fahrenheit by 2100, if no changes are made.
In the third report, the authors laid out a series of possible approaches to stop rising emissions, including expanding existing policies such as fuel taxes and carbon emissions limits such as those set in the Kyoto protocol. They also suggested increasing research on alternative energy options such as solar, wind and nuclear power, and on developing more energy-efficient buildings.
Tufts University environmental policy professor William Moomaw, a co-author of the report's chapter on energy options, told the New York Times that he believes major changes in energy use are possible.
"Here in the early years of the 21st century, we're looking for an energy revolution that's as comprehensive as the one that occurred at the beginning of the 20th century when we went from gaslight and horse-drawn carriages to light bulbs and automobiles," he said. "In 1905, only 3 percent of homes had electricity. Right now, 3 percent is about the same range as the amount of renewable energy we have today. ... That suggests to me it may not be impossible to make that kind of revolution again."
The report was finalized just before dawn Friday in Bangkok, and officials said that there were relatively few last-minute disagreements among government officials, according to the New York Times.
Some news reports said that Chinese officials had initially resisted language that suggested stabilizing concentrations of greenhouse gasses at 445 parts per million by 2015, saying that such limits would impede its economic growth. China is the world's second-largest emitter of greenhouse gasses, after the United States.
However, the final report included the language, and Chinese delegate Zhou Dadi told the AP that "the Chinese government was constructive and was contributing to making the report reflect the science. We are not threatened by the report."
Meanwhile, James Connaughton, chairman of the White House Council on Environmental Quality, raised concerns over the predicted 3 percent reduction in global GDP growth that meeting the lowest emissions targets would cause. "It would cause a global recession," he said in a press briefing.
But many other government officials around the world welcomed the report's findings. "The report shows -- and this is encouraging -- that ambitious climate protection is economically manageable," German government spokesman Ulrich Wilhelm said.