Bill McGuire: Why we should forget about the 1.5C global heating target

The goal of 1.5C by 2030 is arbitrary and now unachievable – yet working to prevent every 0.1C rise can still give us hope

The 33 million people displaced from their homes in Pakistan might justifiably say we have reached the temperature rise at which climate change becomes dangerous. Photo: AP/Zahid Hussain

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.