Why we should forget about the 1.5C global heating target

‘The 33 million people displaced from their homes in Pakistan might justifiably say climate change has already become dangerous.’ Photograph: Akram Shahid/AFP/Getty Images

Keeping the global average temperature rise (since pre-industrial times) below 1.5C is widely regarded as critical if we are to sidestep dangerous, all-pervasive climate change.

This idea of a 1.5C temperature threshold is in the news again because just-published research has revealed that several catastrophic climate tipping points are in danger of being crossed at around this level of warming, including collapse of the Greenland and west Antarctic ice sheets, which would lock in about 12 metres of sea-level rise.