The latest news about climate change on Sunday is stark. A United Nations panel has warned that governments are not doing enough to avert profound risks in the coming decades.
But not only is there still time to head off the worst, the political will to make a change seems to be gaining popularity around the world.
In a report, the Intergovernmental Panel on Climate Change found that decades of foot-dragging by political leaders had propelled humanity into a critical situation, with greenhouse emissions rising faster than ever.
While it remains technically possible to keep planetary warming to a tolerable level, only an intensive push over the next 15 years to bring those emissions under control can achieve the goal, the committee has found.
“We cannot afford to lose another decade,” said Ottmar Edenhofer, a German economist and co-chairman of the committee that wrote the report. “If we lose another decade, it becomes extremely costly to achieve climate stabilization.”
The good news is that ambitious action is becoming more affordable, the committee found. It is increasingly clear that measures like tougher building codes and efficiency standards for cars and trucks can save energy and reduce emissions without harming people’s quality of life, the panel found. And the costs of renewable energy like wind and solar power are falling so fast that its deployment on a large scale is becoming practical, the report said.
Moreover, since the intergovernmental panel issued its last major report in 2007, far more countries, states and cities have adopted climate plans, a measure of the growing political interest in tackling the problem. They include China and the United States, which are both doing more domestically than they have been willing to commit to in international treaty negotiations.
Yet the report found that the emissions problem is still outrunning the determination to tackle it, with atmospheric carbon dioxide levels rising almost twice as fast in the first decade of this century as they did in the last decades of the 20th century.
That reflects a huge rush to use coal-fired power plants in developing countries that are climbing up the income scale, especially China, while rich countries are making only slow progress in cutting their high emissions, the report said.
The report is likely to increase the pressure to secure an ambitious new global climate treaty that is supposed to be completed in late 2015 and take effect in 2020. But the divisions between wealthy countries and poorer countries that are making such a treaty difficult, and have long bedeviled international climate talks, were on display yet again in Berlin.
Some developing countries insisted on stripping charts from the report’s executive summary that could have been read as requiring greater effort from them, while rich countries — including the United States — struck out language that might have been seen as implying that they needed to write big checks to the developing countries.
Both points survived in the full version of the report, but were deleted from a synopsis meant to inform the world’s top political leaders.
The new report does not prescribe the actions that governments need to take. But it does make clear that putting a price on emissions of carbon dioxide and other greenhouse gases, either through taxes or the sale of emission permits, is a fundamental approach that could help redirect investment toward climate-friendly technologies.
If climate targets are to be met, the report said, annual investment in electrical power plants that use fossil fuels will need to decline by about 20 percent in the coming two decades, while investment in low-carbon energy will need to double from current levels.
The report warns that if greater efforts to cut emissions do not begin soon, future generations seeking to limit or reverse climate damage will have to depend on technologies that permanently remove greenhouse gases from the air; in effect, they will be trying to undo the damage caused by the people of today.
But these technologies do not exist on any appreciable scale, the report said, and there is no guarantee that they will be available in the future, much less that they will be affordable.
The intergovernmental panel warned that the longer countries delayed aggressive action, the more difficult it would be to limit global warming to the level that the international community has agreed to, namely a rise in the global average temperature of no more than 3.6 degrees Fahrenheit (2 degrees Celsius) above the preindustrial level.
Scientists fear that exceeding that level could produce drastic effects, such as the collapse of ice sheets, a rapid rise in sea levels, difficulty growing enough food, massive die-offs of forests, and mass extinctions of plant and animal species.
The Intergovernmental Panel on Climate Change is a United Nations body that includes hundreds of scientists, economists and other experts. The group periodically reviews the science and economics of climate change and issues major reports every five or six years. Along with Al Gore, it won the Nobel Peace Prize in 2007 for calling attention to the climate problem.
The new report, dealing with ways to limit the growth of the emissions that are causing climate change, is the third in recent months.
A report released in Stockholm in September found a certainty of 95 percent or greater that humans are the main cause of global warming, and a report released in Yokohama, Japan, two weeks ago said profound effects were already being felt around the world, and were likely to get much worse.
The latest report found that if countries keep stalling on tougher climate rules, trillions of dollars will be invested in coming years in power plants, cars and buildings that use too much energy from fossil fuels.
The result, the report said, would be an emissions path that would be almost impossible to alter in time to get to the very low carbon pollution levels that scientists think are necessary by 2050.