It isn’t just a lot of hot air.

The nation’s top meteorological organization debunked Environmental Protection Agency head Scott Pruitt’s claim that carbon dioxide is not a main factor in climate change, saying it’s a fact based on “indisputable findings.”

“This is a conclusion based on the comprehensive assessment of scientific evidence. It is based on multiple independent lines of evidence that have been affirmed by thousands of independent scientists and numerous scientific institutions around the world,” the American Meteorological Society wrote in a letter to Pruitt on Monday.

“We are not familiar with any scientific institution with relevant subject matter expertise that has reached a different conclusion.”

In an interview last week, Pruitt said carbon dioxide is not the pollutant it’s made out to be.

“I would not agree that [carbon dioxide is] a primary contributor to the global warming that we see,” he told CNBC’s “Squawk Box.”

The meteorologists said he’s flat-out wrong.

“In reality, the world’s seven billion people are causing climate to change and our emissions of carbon dioxide and other greenhouse gases are the primary cause,” said the letter, signed by AMS executive director Keith Seitter.

Pruitt added during the interview that the record is still unsettled — a statement at odds with the agency he runs, which determined in 2009 that carbon dioxide and five other greenhouse gasses are a threat to public health.

“But we don’t know that yet. … We need to continue the debate and continue the review and the analysis,” said Pruitt, who sued the agency 14 times when he was the attorney general of Oklahoma.

The AMS urged him not to cloud established scientific fact.

“But mischaracterizing the science is not the best starting point for a constructive dialogue,” the letter said. “We hope that you will reconsider your stance on the science, and then help lead the nation and the world to consider, first, options for action, and then the course to be followed.”

President Trump is expected to slice the EPA’s budget by 25 percent and cut 3,000 jobs when he unveils his first budget later this week.