Earth’s surface temperature has been 1.5°C hotter than the pre-industrial average for 21 of the last 22 months.
The 2015 Paris agreement committed countries to keeping the global temperature increase “well below 2°C”, which is widely interpreted as an average of 1.5°C over a 30-year period. The Paris agreement has not yet failed, but recent high temperatures show how close the Earth is to crossing this critical threshold.
Climate scientists have, using computer simulations, modelled pathways for halting climate change at internationally agreed limits. However, in recent years, many of the pathways that have been published involve exceeding 1.5°C for a few decades and removing enough greenhouse gas from the atmosphere to return Earth’s average temperature below the threshold again. Scientists call this “a temporary overshoot”.
