Truth about climate change

We’re looking back at 10 of our recent fact-checks on climate change in light of the United Nations summit in New York this week. These fact-checks cover some of the key points of the climate change debate.

1. "Climate change is a hoax." - Pants on Fire.

Earlier this year we looked at a detailed video from Louisiana congressional candidate Lenar Whitney, who repeated the assertion that climate change is a hoax. We found - as we have before - that there’s an overwhelming consensus among respected scientists that human-caused global warming is real. In this fact-check, we looked at some of Whitney’s supporting evidence to argue that global warming is a hoax and found that it was weak. We rated her statement Pants on Fire.

2. The United States is the leading nation in the world "with the highest amount of doubt about the conventional wisdom of climate change." - Mostly True.

Talk show host Rush Limbaugh says he doesn’t believe in climate change, and he gives himself the credit for convincing others of the same. Recent reports showed the United States is the leading nation in the world "with the highest amount of doubt about the conventional wisdom of climate change, " Limbaugh said in July.

Aside from Limbaugh’s bragging, PunditFact looked at recent studies on global opinions on health care. We found that that a good proportion of developing countries have higher rates of doubt than the United States. But among its peers, the United States is one of the most - if not, the most - skeptical when it comes to believing climate change has human factors. So we rated Limbaugh’s statement Mostly True.

3. "Virtually no Republican" in Washington accepts climate change science. - Mostly True.

California has been in the forefront of new regulations to address the carbon emissions that are causing climate change. Gov. Jerry Brown said that’s in part because Washington won’t act. Brown told journalist George Stephanopolous in May that "there's virtually no Republican who accepts the science that virtually is unanimous. There's just political denial for various reasons, best known to those people who are in denial."

We found relatively few Republican members of Congress who accept the prevailing scientific conclusion that global warming is both real and man-made; we named them in our fact-check and concluded that Brown’s qualified statement was Mostly True.

4. Cap and trade legislation "was originally a Republican idea." - Mostly True.

Democratic National Committee chair Debbie Wasserman Schultz also serves as a member of Congress who represents parts of south Florida. She said in May that rising sea levels and flooding will make part of her district uninhabitable in the future, and she called for Republican support on solutions, singling out a cap and trade plan as an area where the parties could agree.

"That was originally a Republican idea. It was developed in the 1970s when the Clean Air Act was initially adopted, " she said.

PolitiFact Florida recapped the history of cap and trade and found that Wasserman Schultz was largely correct, though it’s important to note that Democrats supported cap and trade at key points. We rated her statement Mostly True.

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