After Pope Francis framed climate change as a moral issue in his second encyclical, conservative Republicans shifted and began to see environmental dilemmas in the same way, according to a new study led by Cornell University communication researchers.

"When Pope Francis issued his encyclical paper in June 2015, he emerged as a strong advocate for climate action," said Jonathon P. Schuldt, assistant professor of communication. "He is in many ways uniquely positioned as a global moral authority - a religious authority - and his position is very visible."

Schuldt, along with Adam R. Pearson of Pomona College and Rainer Romero-Canyas and Dylan Larson-Konar, both of the Environmental Defense Fund, sought to understand a mechanism for changing public opinion about climate change. Their research, "Brief Exposure to Pope Francis Heightens Moral Beliefs About Climate Change," was published online in the journal Climatic Change, Dec. 30.

The pontiff addressed waste, culture and modern day ills in the encyclical. Climate change is a global problem with grave environmental, social, economic and political implications, the pope wrote. Many of the world's poor live in areas particularly affected by phenomena related to global warming, and their subsistence depends on keeping Earth healthy. They have few resources to help them adapt to climate change, the pope said.

For this research, more than 1,200 U.S. adults were asked for their moral beliefs about climate change. Half of those polled were briefly shown a photograph of the pope prior to answering questions, and the others were shown his picture afterward.

The researchers found that seeing the pope's picture before the belief questions increased and shifted moral perceptions of wide segments of the public, Schuldt said.

When answers were compared along party lines, the percentage of Republicans jumped the most. Of those who did not see the pope's picture prior to reporting their opinions, only 30 percent agreed that climate change is a moral issue. For Republicans who saw the pontiff's photo prior to the questions, this figure grew to 39 percent.

"On the whole, Republicans are less likely to see climate change as a moral issue. But, if they are shown a photo of the pope beforehand, they are more likely to," Schuldt said.

Democrats and progressives do not shift much on this issue, Schuldt said: "Most Democrats already see climate change as a moral and ethical issue. Republicans have more room to move."

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