One of the hottest debates in the country is about global warming. Is it over-hyped? The public doesn't think so. A new CBS News/New York Times poll shows that more than half of those surveyed said global warming is a serious problem that's having a serious impact right now.
But more Democrats feel that way than Republicans: 71 percent to 42 percent.
Check out the candidates' full responses in our "Primary Questions" video library.
Edwards: It seems to me that every time we get more scientific information it indicates the problem is more severe, more serious than we though. So, no, I don't think it's being over-hyped.
Couric: What three things would you do about it?
Edwards: Have a national cap on carbon emissions. I'd make polluters pay, people who below the cap are still putting out carbon dioxide. And that money from making the polluters pay for a permit to do that should be invested in clean, renewable sources of energy, wind, solar, fuels. We have to clean up our act. As we start cleaning up our act, I think we're in a place to be able to go to China, to India, to the other countries that need to be part of the solution and say "we're developing the technology. We're willing to make this technology available to you. But we're gonna have to solve this problem together."
Thompson: There are a lot of unanswered questions. We don't know to the extent this is a cyclical thing. This may or may not effect very much. The extremists, I think, are the ones who want to do drastic things to our economy before we have more answers as to how much good we can do, and whether or not people in the other parts of the world are going to contribute. It's the fact that our entitlements are bankrupting the next generation. We're spending the money of those yet to be born and we can't continue that way.
Couric: You think that the state of entitlements is a more serious problem than global warming?
Thompson: It's a more obvious problem. I mean, ultimately global warming may be a greater problem. I don't think we know the answer to that. I can't give you a list of specific items I would address. I think research and development has got to be at the top of that list.
Clinton: I don't think that it's over-hyped. I think we have time but we have to start acting now. I would put a heavy emphasis on energy efficiency. We cab drastically lower our use of electricity, thereby drastically lowering our use of coal-powered electricity. We need to have higher gas mileage and I have advocated 40 miles per gallon by 2020 and I believe that's achievable. But we're gonna have to help Detroit do it. I don't want to sacrifice jobs to do it. I want to leave the world in a post-Kyoto agreement that I hope we can get resolved and signed that will include China and India.
Want to have energy independence bonds like we had during the World War when we had war bonds. If we have people buying those bonds, we will take that money and put it into what I would call a strategic energy fund. This has to be change from the lowest level of the family and business level all the way up to the national and international level.
McCain: I have been to Greenland, I have been to the South Pole. I've been to the Arctic and I know it's real. I believe that we've got to go back to nuclear power. We've got to do alternative energy. We've got to have a cap and trade proposal which Joe Lieberman and I have proposed.
We need to do green technologies. Let me put it this way to you. Suppose I'm wrong, there's no such thing as climate change, and we adopt green technologies. Then we've just left our kids a better world. Suppose I am right and we do nothing? Then what kind of planet have we handed to our children.
I've been involved in this effort for many years. And we've got to act. And unfortunately, we have not acted either as a federal government or a Congress.
Couric: Why has it taken so long, Senator?
McCain: Special interests. It's the special interests. It's the utility companies and the petroleum companies and other special interests. They're the ones that have blocked progress in the Congress of the United States and the administration. That's a little straight talk.
Obama: No, I think they're serious. We have to take significant steps now to deal with it. So I've put forward a very substantial proposal to get 80 percent reductions in greenhouse gases by 2050. That is going to require that we change how power plants operate. That's going to require that we increase fuel efficiency standards, that we develop clean and renewable sources like solar and wind and biodiesel.
And, you know, we're going to have to charge for pollution and create a market for pollution abatement and create green technologies that can, over the long term, generate jobs and entrepreneurial opportunities all over the country. But we've got a moral obligation to deal with this. And you're already seeing the effects in not just the United States but all around the world in ways that ultimately could affect our national security.