The chance of at least one of the next five years exceeding 1.5°C has risen steadily since 2015, when such a chance was close to zero.
There is an 80 per cent likelihood that the annual average global temperature will temporarily exceed 1.5°C above pre-industrial levels for at least one of the next five years, according to a new report from the World Meteorological Organization (WMO). This is a stark warning that we are getting ever closer to the goals set in the Paris Agreement on climate change, which refers to long-term temperature increases over decades, not over one to five years.
The global mean near-surface temperature for each year between 2024 and 2028 is predicted to be between 1.1°C and 1.9°C higher than the 1850-1900 baseline, according to the WMO report. It says that it is likely (86 per cent) that at least one of these years will set a new temperature record, beating 2023 which is currently the warmest year.
There is a 47 per cent likelihood that the global temperature averaged over the entire five-year 2024-2028 period will exceed 1.5 °C above the pre-industrial era, says the WMO Global Annual to Decadal Update – up from 32 per cent from last year’s report for the 2023-2027 period.
The chance (80 per cent) of at least one of the next five years exceeding 1.5°C has risen steadily since 2015, when such a chance was close to zero. For the years between 2017 and 2021, there was a 20 per cent chance of exceedance, and this increased to a 66 per cent chance between 2023 and 2027.
Climate hell
The update is produced by the UK’s Met Office, which is the WMO Lead Centre for Annual to Decadal Climate Prediction. It provides a synthesis of predictions from WMO designated Global Producing Centres and other contributing centres.
It was released to coincide with a major speech by United Nations Secretary-General António Guterres calling for much more ambitious climate action ahead of the G-7 summit in Italy 13-15 June.
“We are playing Russian roulette with our planet,” said Mr Guterres. “We need an exit ramp off the highway to climate hell. And the good news is that we have control of the wheel. The battle to limit temperature rise to 1.5 degrees will be won or lost in the 2020s – under the watch of leaders today.”
According to the UN, the science is clear: to avert the worst impacts of climate change and preserve a liveable planet, global warming needs to be limited as much as possible and as a matter of urgency.
Under the Paris Agreement, countries agreed to substantially reduce global greenhouse gas emissions to enable the long-term global average surface temperature increase to be kept well below 2°C above pre-industrial levels and pursue efforts to limit it to 1.5°C.
At COPs 26, 27, and 28, countries emphasized that the impacts of climate change would be much lower at a temperature increase of 1.5°C, compared with 2°C, and expressed their firm resolve to pursue efforts to limit global warming to 1.5°C.
Monthly and annual breaches of 1.5°C do not mean that the world has failed to achieve the Paris Agreement’s temperature goal, which refers to a long-term temperature increase over decades, not individual months or years. Temperatures for any single month or year fluctuate due to natural variability, including El Niño/La Niña and volcanic eruptions.