Pope Francis steps up campaign on climate change, to conservatives' alarm

Speaker John A. Boehner, Republican of Ohio, invited the pope to speak to Congress, but some Catholics say that Mr. Boehner should prepare for some uncomfortable moments. Mr. Boehner, who is Catholic, has often criticized the Obama administration for what he calls its “job killing” environmental agenda.

“I think Boehner was out of his mind to invite the pope to speak to Congress,” said the Rev. Thomas Reese, an analyst at the National Catholic Reporter. “Can you imagine what the Republicans will do when he says, ‘You’ve got to do something about global warming’? ”

In addition, a number of Catholics — including Jeb Bush, Marco Rubio, Bobby Jindal, Chris Christie and Rick Santorum — are gearing up to compete for the Republican presidential nomination, and most of them question the science of human-caused climate change.

Several conservative Catholic intellectuals who expect the pope’s message to bolster the vast majority of scientists who hold that climate change is induced by human activity, including Robert P. George, a Princeton law professor, have published articles reminding Catholics that papal pronouncements on science are not necessarily sound or binding.