May 12

Yesterday, Florida senator Marco Rubio all but announced that he’ll be running for president in 2016. In the process, he offered some vigorous climate denialism that should please the Republican primary electorate: “Our climate is always changing,” he said, noting that human activity has nothing to do with it and that any efforts to do something about it “will destroy our economy.”

So this is a good time to recap what the other potential GOP presidential contenders has said about climate in the past.

Last time around, almost all the 2012 candidates had embarrassing flirtations with climate realism in their pasts. Just a few years prior, the common Republican position had been that 1) climate change is occurring, and 2) the best way to deal with it is not through heavy-handed government regulation, but by harnessing the power of free markets in a “cap and trade” system, which worked so well to reduce acid rain. Mitt Romney, Newt Gingrich, Tim Pawlenty, and John Huntsman had all previously endorsed cap and trade.

But the current crop of potential nominees have purer records when it comes to climate denialism:

Rand Paul: The Kentucky senator’s position is less complete denialism and more a kind of post-modern commitment to the inevitability of uncertainty, where all knowledge is subjective. In a recent interview, Paul said the earth goes through periods of time when the climate changes, but he’s “not sure anybody exactly knows why.” He threw in some environmentalist-bashing: “The earth’s 4.5 billion years old, and you’re going to say that we had four hurricanes and so it proves a theory?” Extra points for knowing the age of the earth, though.

Chris Christie: The New Jersey governor will have some explaining to do to GOP voters. Here’s what he said in 2011: “When you have over 90 percent of the world’s scientists who have studied this stating that climate change is occurring and that humans play a contributing role it’s time to defer to the experts.” Lately, he has been mostly avoiding the issue.

Ted Cruz: The Texas senator is emphatically convinced the whole thing is a hoax. “The last 15 years, there has been no recorded warming,” he told CNN earlier this year. “Contrary to all the theories that they are expounding, there should have been warming over the last 15 years. It hasn’t happened.” Cruz’s ideas about energy policy basically come down to all fossil fuels, all the time.

Bobby Jindal: While I was unable to find an explicit statement the Louisiana governor has made about climate change, he has been a soloist in the “Drill, baby drill!” chorus. In a 2012 Wall Street Journal op-ed advocating for more production of fossil fuels, Jindal wrote that Obama “must put energy prices and energy independence ahead of zealous adherence to left-wing environmental theory.”

Scott Walker: The Wisconsin governor hasn’t gone into detail about his views on climate change, but his actions suggest he’ll be good with the base. He signed a “no climate tax” pledge promising not to support any legislation that would raise taxes to combat climate change and has been a keynote speaker at the climate-denying Heartland Institute. He also apparently dislikes recycling.

Jeb Bush: While the former Florida governor has been quiet on the issue of late, in the past he’s cast himself as a skeptic, if not quite an outright denier. “I think global warming may be real,” he said in a 2011 interview. “It is not unanimous among scientists that it is disproportionately manmade. What I get a little tired of on the left is this idea that somehow science has decided all this so you can’t have a view.”

Mike Pence: The Indiana governor has in the past promoted the false idea that there are significant numbers of scientists who don’t believe climate change is occurring. “In the mainstream media, there is a denial of the growing skepticism in the scientific community on global warming,” he said in a 2009 interview, though he did allow: “I’m sure reducing CO2 emissions would be a positive thing.”

Paul Ryan: Ryan hasn’t made many explicit public comments on climate change, but in 2009 he wrote an op-ed decrying efforts to reduce carbon emissions and claiming that climate scientists are using “statistical tricks to distort their findings and intentionally mislead the public on the issue of climate change.” And his budget would remove the EPA’s authority to regulate carbon emissions.

Rick Santorum: If you’re looking for the most climate denialist candidate running in 2016, Santorum is definitely your man. He thinks global warming is “a beautifully concocted scheme” by liberals. “The dangers of carbon dioxide?,” he said in a 2012 speech. “Tell that to a plant, how dangerous carbon dioxide is.” And at the time he proudly proclaimed: “The apostles of this pseudo-religion believe that America and its people are the source of the earth’s temperature. I do not.”

Mike Huckabee: The former Arkansas governor has traveled farther than any other candidate. In 2007, he supported a cap and trade system to reduce carbon emissions. Then in 2010, he denied ever having said any such thing: “I never did support and never would support it — period.” And these days, he gets on the radio with Sen. Jim Inhofe and jaws about what a hoax the whole thing is.

So there you have it: Only one of the potential contenders (Chris Christie) seems willing to say that human activity is a significant cause of climate change.