Richard Thomas, biology professor at West Virginia University, has been studying the impact of carbon emissions on forests for years and said the damage is clear.
When the scientific community found consensus that sulfur dioxide and nitrogen oxide emissions from power plants were creating acid rain, Thomas said, they helped get Congress to pass the 1970 Clean Air Act.
"It shows that Congress can work together with the president,'' he said, and it paid off big for the Eastern U.S.
"And it's time we recognize there is consensus on climate change as well,'' Thomas said.
But economist Myron Ebell, director of the Competitive Enterprise Institute, says consensus is limited to this: Carbon dioxide is a greenhouse gas, more is going into the atmosphere, and it will affect climate.
"Everything else beyond that consensus is politics,'' he said, including how much it will warm the planet and whether that warming is harmful or even significant.
Limiting energy production and use are tactics for solving what he calls "a very speculative problem.''
"The policies being promoted are insane,'' Ebell said. "If you believe energy poverty is a good thing, you should support controls on carbon emissions. But most of the world disagrees with that.''
Like-minded professor John Christy, director of the Earth System Science Center at the University of Alabama in Huntsville, called affordable energy "the basis of our standard of living today.''
While reducing CO2 emissions may or may not affect climate change, Christy said he's certain it would raise energy costs.
"I've lived in Africa, and I can assure you that without energy, life is brutal and short,'' Christy said. "...We are not bad people because we produce carbon dioxide.''
But Scott Denning, a professor at Colorado State University's department of atmospheric science, said the anti-regulation camp should stop telling "scary stories.'' Our ancestors once used candles and horses but adopted new technologies like oil and electricity even when they were more expensive.
"I think when people tell scary stories about how our society can't adapt to a changing environment, they do a disservice to the power of the free market,'' he said. "I have faith in our descendants being as ingenious, as creative, as hardworking, as industrious as our ancestors were.
"I believe they can solve this problem,'' Denning said, "and it won't bankrupt our society.''