We’ve all heard the glum prognosis that climate change will ultimately bring an end to human existence, but this new study says it could happen sooner than we thought. According to an analysis published by an Australian think-tank called the Breakthrough National Centre for Climate Restoration, climate change may end human civilization in just 30 years. The report says that on humanity’s current trajectory, “planetary and human systems [are] reaching a ‘point of no return’ by mid-century, in which the prospect of a largely uninhabitable Earth leads to the breakdown of nations and the international order.”

This morbid prediction is based on the fact that the Earth’s temperature is likely to rise by at least three degrees, which could facilitate the quick collapse of ecosystems like coral reefs, the Amazon rainforest, and the Arctic. This could cause a billion people to relocate from their now-unlivable conditions, and around two billion to face scarce water supplies. Agriculture in many parts of the world would also collapse, meaning food production could grind to a halt.

According to the report, “Even for 2°C of warming, more than a billion people may need to be relocated and in high-end scenarios, the scale of destruction is beyond our capacity to model with a high likelihood of human civilization coming to an end.”

And this isn’t just speculation and hearsay, either. The report has been endorsed by retired Admiral Chris Barrie, who was chief of the Australian Defence Force from 1998 to 2002. According to him, the study reveals “the unvarnished truth about the desperate situation humans, and our planet, are in, painting a disturbing picture of the real possibility that human life on Earth may be on the way to extinction, in the most horrible way.”

The outlook may not inspire optimism, but it should inspire a resolve to combat climate change more fiercely than ever.

H/T: VICE