Scientists say pope may be the key player on climate change

Gregg Zoroya | USA TODAY Opinion

Show Caption Hide Caption Pope climate encyclical has scientists hopeful Shannon Green and Gregg Zoroya discuss the encyclical from Pope Francis to be issued by the Vatican on Thursday, June 18, and the excitement it engenders among climate scientists.

Corrections & Clarifications: A previous version of this article misstated Pope Francis' chemistry education. He studied chemistry and worked as a chemist prior to attending the seminary.

Scientists weary after years of often vicious opposition by doubters of their climate-change findings see this year as crucial to the planet's future because of a religious document expected from Pope Francis on Thursday.

The rare encyclical, or teaching letter, expected to promote climate action as a moral imperative could do more to slow global warming than international negotiations this year to limit greenhouse gas emissions, scientists say.

"The encyclical is going to go out to over 1 billion Catholics — that's a way of getting a message across to a segment of society that the scientific community could never do," said an excited Jeff Kiehl with the National Center for Atmospheric Research. "I mean it's just unbelievable."

"I'm not a religious person at all," said Gavin Schmidt, a NASA climatologist. But he sees faith-based efforts to shift thinking on climate action as very promising.

"The pope's encyclical is probably going to have a bigger impact than the Paris negotiations," he said.

The 21st United Nations conference on climate change, which is set for December in Paris with more than 190 countries, hopes to reach agreement on emissions that would keep further warming of the planet less than 2 degrees Celsius, or 3.6 degrees Fahrenheit, beyond global temperature at the time of the Industrial Revolution.

Catholic leaders expressed hope last week that the encyclical will transcend partisan fighting over the causes of climate change, arguments that have stymied efforts in the U.S. Congress and elsewhere to reduce greenhouse emissions.

"This encyclical is aimed at everyone," Pope Francis said Sunday. "Let us pray that everyone can receive its message and grow in responsibility toward the common home that God has entrusted to us."

He said Friday that to show unity of purpose, the document will be unveiled by three people: a Catholic cardinal, a Christian Orthodox church leader and a climate scientist the Vatican identified as an atheist.

The pope, who studied chemistry and worked as a chemist before entering the seminary, has a history of environmental concern. He said in January that science is largely settled on the causes of climate change and that greater stewardship of God's creation is necessary.

"Mostly, in great part, it is man who has slapped nature in the face," he said.

There has already been push back from conservative Catholic religious writers and figures such as Republican presidential candidate Rick Santorum, who is Catholic, accusing the pope of being alarmist.

"The church has gotten it wrong a few times on science, and I think that we probably are better off leaving science to the scientists," Santorum recently told a radio-talk show host. "When we get involved with political and controversial scientific theories, then I think the church is probably not as forceful and credible."

Scientists, however, applaud the pope for urging moral choices in a discussion dominated by the recitation — or among deniers, the misrepresentation — of facts.

"Many people have this rosy view that there's this knowledge deficit, and that if we just provided more information or if we explain the science better or if we package it better, maybe with colored graphics, or write another scientific paper, that will be the one to convince (doubters)," said climate scientist Katharine Hayhoe of Texas Tech University.

"But the reality is it's not a scientific issue (any longer). It is an ideological issue. We have to appeal to people based on values. Not just on data and facts. And for me as a scientist to say that is very unusual," Hayhoe said. "So from that perspective the pope is a very effective messenger."

Scientists say that some predicted changes such as a warming Arctic, rising sea levels, more intense heat waves, extreme snow and rain storms and animal or plant extinctions are happening faster than anticipated. Frustration over a lack of response by the federal government has been growing.

A website created by Australian science communicator Joe Duggan called "Is this how you feel?" contains dozens of letters from climate scientists angry or stunned by a lack of forceful action by policymakers.

"I feel like nobody's listening," Australian research fellow Helen McGregor wrote last fall.

"There is so much noise around the issue that I often feel compelled to be outraged by our own inability as a species to respond," scientist Carlo Buontempo wrote, "But the truth is that more often than not I just feel tired."

The vast majority say they remain optimistic. Last year, a consortium of North American universities created a speakers network for climate change discussion and more than 370 scientists have since signed up to give talks at libraries, chambers of commerce, schools, colleges and community clubs.

But change still seems too slow, many say.

"As a scientist, I can say that it is possible for us to prevent truly catastrophic, potentially irreversible climate change. But I cannot say as a scientist whether or not we will find the will to do what's necessary," said Michael Mann, a climate scientist at Penn State University who published a book on the role of science deniers in subverting global warming discussions.

Mann said only strong public outcry can force policy changes, and this is where the encyclical is crucial.

"There are a lot of people out there who thus far have been either skeptical or indifferent," Mann said. "I think this (encyclical) will make a difference for them."