As he flew home over the Caribbean islands that had been devastated by Hurricane Irma, Pope Francis had an exasperated explanation for people who refuse to accept man-made global warming as fact:  "Man is stupid," he said.

You've earned this Papal Double Facepalm

The Pope was referring to the Bible's old testament book of Proverbs which deals with people who resist correction in matters of knowledge.  "Whoever loves discipline loves knowledge, but whoever hates correction is stupid," reads Proverbs 12:1, and it goes on from there.  But even as the guy whom Roman Catholics believe is infallible in matters of faith, the former chemist knows when it's time to talk with experts:

"Anyone who denies (climate change) should go to the scientists and ask them.  They speak very clearly," Pope Francis implored, "Climate change is having an effect, and scientists are telling us which path to follow.  And we have a responsibility - all of us.  Everyone, great or small, has a moral responsibility.  We must take it seriously."

Several climate scientists are warning that the number of powerful storms all hitting the US - Harvey in Texas, Irma in Florida and the Southeast, and Hurricane Jose now tracking towards the southern Atlantic coast - shows that global warming has raised the ocean's temperature, and warmer water feeds stronger tropical storms.

"Climate change may not have caused Hurricane Irma, but it is making its impacts a whole lot worse," said Dave Reay, Professor of Carbon Management at the University of Edinburgh, to the Independent.  "Rising sea levels and a warmer, wetter atmosphere are combining to intensify flood risks all around the world."  Professor Ray hit Donald Trump for pulling the US out of the Paris Climate Agreement:  "For many folk in Texas and Florida that decision must now be looking pretty short-sighted."

Francis warned that "history will judge those decisions" man makes today, and that "will go down" if we fail to make the correct ones.

The Pope was flying from a visit to Colombia back home to the Vatican when he made his comments in response to questions asked by an Italian reporter.