The 2015 encyclical, Laudato Si’ — on care for our common home — clearly laid out Pope Francis’s hopes that society could work together and engage in protecting the environment as a moral imperative. It placed science firmly in the frame while linking society to environmental issues and calling for the Catholic Church to enter the climate change dialogue. Released in June 2015, it added to the conversation leading to the climate Conference of the Parties (COP) in Paris, which resulted in the Paris Agreement, and was a timely statement from an important leader.

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Such was the Pope’s passion for social justice and fairness, alongside ecology and the environment, that he continued to advocate and educate on the issue. In 2019, he stated that there was a climate emergency and called for better protections for the poor, asking for a just transition, and committed the Church to climate action.

The encyclical was followed by a second published piece, Laudate Deum, an apostolic exhortation released in 2023, which called for greater action, stating “with the passage of time, I have realized that our responses have not been adequate, while the world in which we live is collapsing and may be nearing the breaking point.” This echoes his statements on a climate emergency made four years earlier.

The 2015 encyclical was widely well received at the time, and upon its release, Nature Climate Change presented a number of commentary articles published in October 2015 from a range of scholars touching on key issues raised as well as areas that were not covered in the encyclical.

Literature that looks at the effects of the encyclical presents a complex picture. For example, one study that looked at attitudes towards climate change and the Pope after publication of the encyclical in the USA found that those aware of the encyclical held more polarized views on climate change than the unaware, and that conservative Catholics were conflicted by the opposing statements from their political party and those of the Pope1. The clash of views highlights the difficulty of communicating polarizing issues.

While a study on 18 Latin American countries based on 2017 survey results found that regional dioceses should engage in the discourse on environmental issues, rather than the call coming from the Pope, to promote climate action, as Roman Catholics were less likely to believe in anthropogenic climate change than those of no or other denomination faith2.

Both these examples showcase that individual minds cannot easily be swayed; yet another study, published in 2019, found that the implementation of a sustainability plan by the Church was a positive effect in increasing environmental awareness and engagement, with this finding based on Internet search data that public interest in the environment seemed to be growing3.

But now ten years have passed, and while we cannot quantify the impact of the Pope’s encyclical, the effects of climate change are being felt around the world. The issue of climate change is still as polarizing as ever, and misinformation and disinformation take up space and play on fears. It is essential that supporting voices are present to counter this noise. This year, Earth Day, on 22 April, had the theme ‘our power, our planet’ — the theme aimed to unite people around renewable energy and to support the green energy transition, but taking the words as they are written is also a powerful message. It resonates with the messages of Pope Francis through the encyclical and his following communications to engage with the dialogue. We should not forget the power of the collective — elected and appointed leaders can make statements supporting or opposing climate action, but the general population has the power to participate to bring about change.