SEN. CHARLES E. GRASSLEY, R-IOWA weighs in

QUESTION: This is Chris Clayton with DTN. I joined a little bit late.

Senator, I was wondering, back on the cap-and-trade and climate legislation, the U.S. Chamber of Commerce wants to kind of essentially have a trial with the EPA debating the science of climate change. And I was wondering, are you convinced greenhouse gas emissions cause climate change and are a threat to human health?

GRASSLEY: Well, I'd be foolish if I didn't give -- I'd be foolish if I didn't give it some consideration because there's a massive amount of scientists that feel that it does. But there's also an increasing number of scientists that have doubt about it.

And so, not being a scientist, I don't know exactly where to say only those things that are really quantifiable, and temperature has risen. But the scientific aspect that I still reserving judgment on is the extent to which it's manmade or natural.

And it's reasonable, considering that there's at least a natural factor in it, because historically, and you can go to the core drillings in the glaciers to get proof of this, that we've had decades and decades, and maybe even centuries of periods of time when there's been a tremendous rise in temperature, and then a tremendous fall in temperature. And all you've got to do is look at the little ice age of the mid-last millennia as an example. And so we've got to single out what's natural and what's manmade before you can make policy.

Now, a lot of members of Congress and most environmentalists are -- are absolutely convinced manmade is the -- is the factor -- chief factor here. But I -- I want to, before I vote on it, be more conclusive in my judgment, and I haven't reached that conclusion at this point.

But it's enough to know that I think that even if it is manmade entirely, and so there's justification for the legislation, you still have to deal with the reality factors that domestically there's a very unlevel playing field between California and New York that benefit financially from it, and the Midwest and the Southeast United States that's going to be hurt; and then the unlevel playing field if you don't include India and China, an unlevel playing field with the United States versus those countries.