It was clear from day one that Pope Francis was going to shake things up in the climate world. On March 13, 2013, the newly elected Pope, then Argentinian cardinal Jorge Mario Bergoglio, took the name Francis, after the 13th century saint of Assisi. Upon hearing the voice of Jesus instructing him to repair a collapsing chapel, St. Francis revitalized chapel and the Catholic Church while celebrating the natural world. It was like the new pope “heard the same message,” says Father Joshtrom Isaac Kureethadam, coordinator of the ecology and creation department at the Vatican’s ministry for promoting integral human development. “It was ‘Francis, Go and repair my house, which is falling into ruin.’ And it’s not just the church, but planet earth, which as we know, is in a very bad state.”
The Pope’s reign, now entering its 10th year, carries a mixed legacy—celebrated for his efforts to protect refugees and broaden the Church’s reach, marred by finance scandals and sexual assault cover-up controversies (his 2022 apology for the physical and sexual abuse of Indigenous children in Canada’s Catholic-run boarding schools was deemed by many activists as too little and too late). But from a climate perspective, his efforts to repair the house of planet earth may be his most enduring. He has dedicated much of his papacy to raising awareness of climate change and how it impacts the world’s people, and he frequently urges care for the planet in his teachings.
What started as a quasi-mystical nod to St. Francis, patron saint of ecology and animals, quickly morphed into a well-constructed strategy to bring the world’s 1.2 billion Catholics into alignment over humanity’s role in causing climate change.
On June 18, 2015, he published Laudato Si’: On Care For Our Common Home, a landmark encyclical, or pastoral letter, to the entire Catholic congregation. The 184-page document lamented environmental degradation and global warming, critiqued consumerism and irresponsible development, and warned of “serious consequences for all of us” if current trends continued. The timing of the encyclical, released six months ahead of the pivotal U.N. climate conference in Paris, was calculated, according to Kureethadam, with a goal of convincing world leaders to set clear targets to limit global warming.
The document laid out the scientific case for human-caused climate change and urged a concrete response that, for the first time, interlaced social justice with environmental stewardship. Before the encyclical, environmental concerns were seen as something only for the elite, says Kureethadam. “Laudato Si’ brought in the moral perspective. [He was saying] if you want to improve the lives of the poor, there’s no other way except by guaranteeing that they have the conditions in which they can live and flourish and survive”—an impossibility given the likely trajectory of climate change.
In drafting Laudato Si’, Pope Francis relied on rigorous scientific research connecting human activities with climate change, bridging the centuries-old divide between religion and science and depriving climate deniers a foothold, at least in the Catholic Church. “The impact was tremendous,” says Ottmar Edenhofer, director of the Potsdam Institute for Climate Impact Research in Germany. “Before Pope Francis, it was by no means clear that the Church was really prepared to take climate science seriously. It is now clear that you cannot be a Catholic and you cannot be a Christian and at the same time deny that climate change is an issue.”
The impact spilled into the policy realm as well, adds Edenhofer, who served as co-chair of the U.N.’s Intergovernmental Panel on Climate Change in the eight years leading up to the 2015 Conference of Parties (COP) negotiations in Paris. The document, which was hugely significant across the Catholic world, paved the way for an influential Vatican presence at the meetings, translating into strong climate commitments from the Polish and Latin American delegations. The Pope’s climate teachings were “a powerful symbol,” says Edenhofer. “The Vatican played a significant role in the negotiations for the Paris Agreement [to limit global warming], and as an actor was very helpful.”
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Six years on, that influence is starting to wane. The annual climate negotiations are now more about financing loss and damage funds and technological debates over fossil fuel drawdowns and carbon capture options—areas where the Pope’s moral authority has little sway. The Vatican only became a party to the U.N. Framework Convention on Climate Change in 2022, and while it too has made commitments to net zero emissions by 2050, the overall impact of doing so is minimal considering the city-state’s tiny size. And the controversies over the past 10 years—even if they don’t involve the Pope directly—have taken a toll.
“When the Pope was elected, there was an enormous amount of goodwill,” says Edenhofer. “The world was ready for his message. But the Catholic Church is no longer a credible institution.” The Pope has repeatedly called on Catholic institutions worldwide to divest from fossil fuel investments, but not all have heeded his message. The Vatican’s own lack of transparency when it comes to financial dealings hasn’t helped, says Edenhofer. “The Catholic Church is incredibly rich, but it’s not clear that investment is consistent with their ethics.”
Tomas Insua, the executive director of the Laudato Si’ Movement, a climate advocacy and activism network that sprung up in the wake of the encyclical, agrees that the Church as a whole could do much more in terms of divestment. But that doesn’t mean that the Pope’s climate message has faded. If anything, says Insua, he was the spark that launched a global climate movement that now counts nearly 1,000 catholic organizations and parishes in 150 countries. “Care for the climate, care for the earth, this is now part of the Church teachings. People around the world are taking up the message and turning it into real action. That is his legacy, and it will endure.”