A prophetic ‘warning to humanity’ giving notice of perils facing the Earth has been issued by more than 15,000 scientists from around the world.

Climate change, deforestation, loss of access to fresh water, species extinctions and uncontrolled human population growth are all threatening mankind’s and the Earth’s future. The letter, originally written in 1992 and signed by 1,500 scientists, argued human impacts on the natural world were likely to lead to ‘vast human misery’ and a planet that was ‘irretrievably mutilated’, but a quarter of a century since a majority of the world’s living Nobel Laureates united to sign a warning letter about the Earth, the global scientific community’s view of the future is even more bleak.

The message, posted online, updates an original Warning from the Union of Concerned Scientists and around 1,700 signatories delivered in 1992. Apart from the hole in the ozone layer, which has now been stabilised, every one of the major threats identified in 1992 has worsened.

Runaway consumption of precious resources by an exploding population remains the biggest danger facing humankind, say the scientists. In the second warning letter to the globe, more than 15,000 scientists from 184 countries said humans had ‘unleashed a mass extinction event, the sixth in roughly 540 million years, wherein many current life forms could be annihilated or at least committed to extinction by the end of this century’. People should eat less meat, have fewer kids, consume less and use green energy to save the planet, the world’s leading scientists urged.

“We are jeopardising our future by not reining in our intense but geographically and demographically uneven material consumption and by not perceiving continued rapid population growth as a primary driver behind many ecological and even societal threats”, it said. “By failing to adequately limit population growth, reassess the role of an economy rooted in growth, reduce greenhouse gases, incentivise renewable energy, protect habitat, restore ecosystems, curb pollution, halt defaunation, and constrain invasive alien species, humanity is not taking the urgent steps needed to safeguard our imperilled biosphere.”