This article is from the archive of our partner National Journal

When the Pope talks, people listen. But as Pope Francis wades into the climate-change debate, will he change any minds?

Francis will host a summit Tuesday in the Vatican on climate change with United Nations Secretary-General Ban Ki-Moon. He is also preparing an encyclical—one of the highest forms of a papal statement—on the subject, expected to be released as early as June. Cardinal Peter Turkson, who has helped draft the encyclical, has said the timing is meant to influence U.N. climate-change talks in Paris at the end of the year.

Don't expect to see the Pope, say, get into how states should comply with the Environmental Protection Agency's power-plant rules or the merits of a carbon tax. The document is expected to focus more on the interaction between humans and the environment from a moral perspective, building on an "integral-ecology" philosophy.

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In public statements, Francis has framed climate change as a moral issue, highlighting its impact on the poor. In the Philippines earlier this year, Francis said climate change was "mostly" man-made, adding that, "in great part, it is man who has slapped nature in the face."

The encyclical "is kind of the premier statement that any Pope can make," said Jame Schaefer, a theology and environmental-ethics professor at Marquette University. "You cannot think about the well-being of the poor and vulnerable and of future generations without recognizing that when the Earth is destroyed, people are hurt and threatened."

Sen. Ed Markey, a Catholic who last year traveled to Rome to discuss climate change with the Pope, said that Francis certainly had the power to reshape the messaging of climate change.

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"He's going to add a big moral dimension to the discussion of climate change," the Massachusetts Democrat said. "He's a Jesuit who taught high school chemistry and believes that science is the answer to our prayers."

The document is sure to light up the environmental community and its allies by bringing a new frame to the ongoing climate debate. They're also hoping it will go further to reach climate skeptics.

A number of the country's high-profile Catholic politicians have cast doubt on the science of climate change, including House Speaker John Boehner and Republican presidential candidate Sen. Marco Rubio. Former Florida Governor Jeb Bush, who has emphasized his Catholic faith, has recently said that he's concerned about climate change but is unsure of man's role in it.

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James Salt, director of the liberal-leaning nonprofit group Catholics United, said that while he sees climate change being elevated among the Church's priorities, he does not believe it will be a defining social issue.

"I would love nothing more than for Catholic voter guides to say, You have to believe in climate change. "¦ But the reality is we're still dealing with an institution that is largely captured by anti-abortion, anti-gay-marriage, religious-freedom adherence issues," said Salt.

The Vatican summit Tuesday is meant to connect climate change to respect for people, including its impact on the poor, victims of human-trafficking, children, and future generations. Among the speakers are U.N. Sustainable Development Solutions Network director Jeffrey Sachs, a representative of the Pontifical Academy of Sciences and a panel of speakers from various world religions. State Department deputy legal adviser Susan Biniaz, who previously led international climate-change negotiations, will represent the Obama administration.

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Studies have shown that religion does not necessarily impact people's views on climate change. A November 2014 survey by the Public Religion Research Institute found that faith groups are divided on climate change, with the typically Republican-leaning groups—like white Catholics and white evangelicals—tending to be skeptics.

Several Senate members who are skeptical of climate change or Obama administration regulations on global warming either declined to comment or get into specifics when asked about the impact of the encyclical. Republican Sen. John Hoeven, for example, said he'd have to "wait and see." Requests for comment from Rubio's office were not returned.

Sen. Joe Manchin, a Catholic who says he believes in climate change but opposes policies restricting fossil fuels, said the Pope could be a "breath of fresh air" on climate change, but he hoped to see a "pragmatic, practical approach" that didn't place the blame on industrial activity.

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Noah Toly, a Wheaton University professor who has studied religion and environmental politics, said it is likely that that climate beliefs won't be changed by the encyclical.

"What's more likely to happen is people who already think climate change is real, serious, and anthropogenic will say, This affects how we want to act, and people who don't are likely to dismiss the teaching or take it piecemeal," said Toly. "They'll say, We need to help the poor or care for the planet, but it's not the cause of man."

Nonetheless, faith and environmental groups alike are preparing to start promoting the encyclical when it's announced. Dan Misleh, executive director of the Catholic Climate Covenant, said he's in conversation with Catholic groups and members of other faiths, green groups, and social organizations preparing to discuss the encyclical.

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Patrick Carolan, executive director of the Franciscan Action Network, said he plans to schedule meetings with Catholics serving in Congress to discuss the encyclical and ask if they're "with the Pope."

"I hope this will change hearts. "¦ This is not a political issue, it's a spiritual and moral one," said Carolan, who will attend a meeting at the Vatican in May for Catholic climate advocates that includes an audience with the Pope.

Not everyone is so sure. Brian Burch, president of CatholicVote.org, said he was worried the Pope's stance would be "misinterpreted" to say that humans are the enemy of the environment. Instead, Burch said, it's likely to simply continue the Church's existing position.

"The Church has always insisted that man is a part of creation and that we have a responsibility to creation and for stewardship of the environment," Burch said. "What is open to debate is the means by which we pursue that goal."

The Vatican has become a powerful ally for climate action. EPA Administrator Gina McCarthy met with cardinals there this year to discuss climate change. The eagerness to engage with the United Nations and the Obama administration on this has led to some early backlash and skepticism of the encyclical. An Investors Business Daily editorial said the Vatican "apparently now has been infiltrated by followers of a radical green movement."

The libertarian Heartland Institute, a climate-skeptic group, has sent members to Rome to push against the encyclical. In a statement, Heartland president Joseph Bast said the Pope was "being misled by 'experts' at the United Nations."

"Though Pope Francis's heart is surely in the right place, he would do his flock and the world a disservice by putting his moral authority behind the United Nations' unscientific agenda on the climate," Bast said.

Misleh of the Catholic Climate Covenant said that he hoped the Pope's messaging would move the discussion beyond the realm of politics and science, which he said could blunt the outrage.

"I'm fearful that, instead of a real dialogue, there will be a shouting match," Misleh said. "I hope we can all agree to treat the planet better and treat each other better, rather than just rehashing the same debates and arguments. With the Pope's moral authority, he can shift the dialogue into that moral realm."

This article is from the archive of our partner National Journal.

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