The public perception of climate change has shifted considerably in recent years from one of significant doubt about the role heat-trapping gases play in global warming to one of general acceptance. Still, there are enough doubters extant to challenge any major effort to reduce the emissions blamed for the phenomenon. A report released by the National Research Council on Thursday makes a persuasive argument that continued reluctance to address the issue exposes current and future generations to considerable risk.

The report, "America's Climate Choice," was requested by Congress in 2008 when Democrats were in the majority. The mission was to develop "action-oriented advice" on how the United States should react to the possible consequences of climate change. The report was prepared by a group that included scientists, engineers, economists and businessmen from diverse backgrounds. The goal, which seems to have been met, was to provide sound, fact-based information in a manner free of the partisan taint that for too long clouded any investigation or discussion of climate change.

'Pressing' need

The report's conclusion is straightforward. Global warming, it concludes, is real, and its effects are already apparent. Moreover, there is what the group uniformly agreed was a "pressing" need for new policies at the national level to limit emissions of the harmful gases, especially carbon monoxide, the primary greenhouse gas. The initial political response to the report and the advice it proffers, unfortunately, was mixed. That's hardly a surprise given the deep political divisions on the topic in Washington.

Despite growing, indeed overwhelming proof that climate change is happening and that it is caused by the burning of fossil fuels, there are those who continue to challenge the science that provides and supports such evidence. That's the view of many of the Republicans who hold the majority in the U.S. House. In addition to those who doubt the science, there are others, including some Democrats, who accept the fact of climate change, but are reluctant to address it through policy and legislative changes because they fear either or both would hurt a fragile economy through increases in already high energy prices. Those beliefs are short-sighted.

Take action now

The report was careful to avoid endorsement of specific changes in policy or law, but it did say that failure to take action now could lead to disastrous problems later. "The risks associated with doing business as usual are a much greater concern than the risks associated with engaging in ambitious but measured response efforts," the authors of the report wrote. "This is because many aspects of an 'overly ambitious' policy response could be reversed or otherwise addressed, if needed, through subsequent policy change, whereas adverse changes in the climate system are much more difficult (indeed, on the time scale of our lifetimes, may be impossible) to 'undo.'" In other words, if action to reduce emissions is not instituted now, it might be too late to take such steps in the future.

Temperatures rising

The report provides ample evidence for the need to act promptly. The Earth's average surface temperature has risen by about 1.4 degrees in the last century. About one degree of that increase has come in the last 30 years, the report indicates. In the United States, average temperatures have increased by more than two degrees in the last 50 years. The report indicated that a "preponderance" of scientific evidence shows that the release of carbon dioxide and other heat-trapping gases is the most likely cause of warming during those 50 years.

The result of such warming is increasingly evident to those who care to examine carefully compiled statistics without bias. Melting ice in the cold regions of the globe has caused a rise in average sea levels around the globe. Rising temperatures have spawned an increase in extreme weather conditions - widespread drought or floods in some places, heavy and more violent storms in others. The council did not offer a specific antidote, but indicated that any useful policy to reduce emissions of gases ideally should include putting a price on carbon dioxide emissions. That's not a new idea, but it is a sound one.

"Putting a price on carbon dioxide emissions, either through a cap-and-trade program or a tax, is a critical step in addressing climate change," said Albert Carnesale, chairman of the panel and chancellor emeritus of the University of California, Los Angeles. That implies that the federal government should act responsibly and quickly to take such regulatory action. That's sensible. Without federal leadership, any effort to reduce emissions through a combination of state, local and industry programs is likely to fail. Still, there are those who doubt the need to address the increasingly pressing issue.

Foe not impressed

Rep. Joe L. Barton, R-Texas and a staunch opponent of additional regulation of carbon emissions, didn't think much of the council's report. "I see nothing substantive in this report that adds to the knowledge base necessary to make an informed decision about what steps - if any - should be taken to address climate change," he said. That mindset, shared by many others, will be difficult to overcome.

Still, the effort to limit greenhouse gases must move forward - and promptly. As the research council report so clearly indicates, failure to develop strong new national policies to limit emissions of greenhouses gases poses a clear and present danger and exposes future generations to profound and irreversible change.