Are humans responsible for global warming--or not? A new report says--yes. Scientists from 113 countriesissued the report Friday--saying they have little doubt global warming is caused by man, and predicting that hotter temperatures and rises in sea level will “continue for centuries” no matter how much humans control their pollution. Okay--does this settle the issue? Not hardly--as two guests on "Squawk Box" proved.

Laurie David is an author and the producer of the film "An Inconvenient Truth," the documentary on global warming with Al Gore. She's also the wife of TV's Larry David--the creator of "Seinfeld" and "Curb Your Enthusiasm." Richard Lindzer is an atmospheric science professor at MIT.

David says this new report makes it clear that there is no more debate on the issue of humans contributing to global warming. And she says that scientists deal in facts--and the facts are now in. She says that when it comes to critics of global warming--you need to look at who is funding them. David said Lindzer has taken money from Exxon Mobil and the oil industry. David also says that the U.S. needs to show leadership in this area--and that you can't expect other countries (such as China) to take up the issue, unless the U.S. does.

Lindzer followed David (they were not on at the same time) and said that he has NOT taken money from Exxon Mobil but said he didn't think there would be anything wrong with that. He said that science is not based on facts--but is more of a mode of inquiry. He says this new report is mainly from bureaucrats. Lindzer went on to say that the recent global warming is so small that it's impossible to distinguish is from the natural variables.

Lindzer said Newsweek magazine reported on the story in 1988--and "claimed" that all scientists were on board about global warming. Lindzer says that's not true and that global warming has become an agenda driven issue and has a lot of "fanatics" behind it.