Pope Francis has died on Easter Monday, 21 April, aged 88, the Vatican has announced.

Elected in 2013 following the resignation of Pope Benedict XVI, he was the head of the Catholic Church for just over a decade.

He will be remembered in part for his efforts to open the eyes of the world’s 1.3 billion Catholics to the dangers of climate change.

Throughout his life, he was vocal about these risks, especially their impact on the world’s poorest and most vulnerable people.

‘The planet being squeezed dry’

During his leadership of the Catholic Church, Pope Francis frequently spoke about climate change.

Perhaps his most striking note on the subject was Laudato si’: On Care For Our Common Home, a 184-page landmark document published in 2015. In this pastoral letter, Pope Francis laments the state of environmental damage and global warming, criticising consumerism and taking aim at the “modern myth of unlimited material progress”.

“It is based on the lie that there is an infinite supply of the earth’s goods, and this leads to the planet being squeezed dry beyond every limit,” he wrote.

The text also lays out the scientific case for human-caused climate change, linking it to a moral perspective and warning of “serious consequences” if things don’t change. Pope Francis left no doubt that he backed the scientific consensus that global warming was down to greenhouse gases released by human activity.

This document also came just six months before COP21 – the UN climate change conference where the historic Paris Agreement was signed. Many believe it, and the Vatican’s involvement in negotiations, had a not insignificant impact on this outcome.

Delegations from Catholic countries made strong climate commitments during this COP. The Pope’s ability to speak to people across many divides paved the way for him to become even more deeply involved in future UN climate change conferences.

The Catholic Church and UN climate conferences

Ahead of COP28 in Dubai in 2023, Pope Francis revisited the topic with an updated treatise on climate change. Laudate Deum is an apostolic exhortation calling for urgent action on the crisis.

“With the passage of time,” he wrote, “I have realised that our responses have not been adequate, while the world in which we live is collapsing and may be nearing breaking point.”

This time, he specifically took aim at citizens of wealthy countries living an “irresponsible lifestyle.” In the US, for example, Pope Francis highlighted that emissions per person were two times higher than in China and seven times more than the average of the world’s poorest countries.

He also pinpointed the continued use of fossil fuels as the primary driver of climate change.

Pope Francis intended to go to COP28 himself, making history as the first Pope to address the climate change conference. Flu and lung inflammation, however, prevented him from travelling to Dubai, with his speech instead read by Vatican Secretary of State Cardinal Parolin.

Again, drawing together moral obligations and scientific consensus, he criticised efforts to shift blame for the climate crisis to the rising population figures in poor countries. Instead, he singled out historic emitters “responsible for a deeply troubling ecological debt”.

Hitting on one of the main topics of COP28, he said it was only fair that these countries that have used excessive amounts of fossil fuels wipe out the debts of poorer nations. Who pays for the loss and damage done by climate change is an argument that still continues to this day.

Pope Francis was once again too unwell to travel to COP29 in Azerbaijan last year but sent a message to the UN climate conference. Vatican’s secretary of state, Cardinal Pietro Parolin, instead delivered his message to world leaders gathered in Baku.

He said that the “real challenge of our century” was indifference towards the climate crisis, emphasising that “indifference is an accomplice to injustice”.

The Pope appealed to countries which have contributed the most greenhouse gases to acknowledge their “ecological debt” to others.

He called for “a new international financial architecture” that was “based on the principles of equity, justice, and solidarity”.

The Catholic Church organises its own climate conference

Throughout his life and even up to the end, Pope Francis continued to highlight issues of inequality in the consequences of climate change.

In 2019, he backed calls for ecocide to be made the “fifth crime against peace” – an evil equivalent to genocide and ethnic cleansing – and declared it a sin. He has met with presidents, prime ministers, heads of state, CEOs, and boards of big companies over the years to talk about the issue.

And in May 2024, he organised the Catholic Church’s own three-day conference on climate resilience at the Vatican. Attendees included 16 mayors of international cities such as London Mayor Sadiq Khan and Paris Mayor Anne Hidalgo, as well as governors from around the world.

Rather than solely focusing on mitigating climate change, it drew attention to the need for human adaptation. The Pope questioned political leaders on whether “we are working for a culture of life or for a culture of death.”

“The wealthier nations, around one billion people, produce more than half of the heat-trapping pollutants,” he told participants of the summit.

“On the contrary, the three billion poorer people contribute less than 10 per cent, yet they suffer 75 per cent of the resulting damage.”

This summit once again saw Pope Francis reiterate his belief that the destruction of the environment is an “offence against God” and a “structural sin” that endangers all people.

It is statements like these that made Pope Francis a respected voice on climate change, with many praising his ability to drive collective action across divides. He will be remembered for his moral leadership that bridged the gap between the interconnected issues of poverty, climate adaptation and the consequences of human-caused global warming.