Many of the gravest threats to humanity are drawing closer, as carbon pollution heats the planet to ever more dangerous levels, scientists have warned.
Five important natural thresholds already risk being crossed, according to the Global Tipping Points report, and three more may be reached in the 2030s if when the world heats 1.5˚C (2.7˚F) above pre-industrial temperatures.
Triggering these planetary shifts will not cause temperatures to spiral out of control in the coming centuries but will unleash dangerous and sweeping damage to people and nature that cannot be undone.
The tipping points at risk include the collapse of big ice sheets in Greenland and the West Antarctic, the widespread thawing of permafrost, the death of coral reefs in warm waters, and the collapse of one atmospheric current in the North Atlantic.