The latest forecast from the World Meteorological Organization (WMO) indicates that there is an 80 per cent likelihood that the world will see the annual average global temperature temporarily exceed 1.5°C above pre-industrial levels for at least one of the next five years.

“WMO is sounding the alarm that we will be exceeding the 1.5°C level on a temporary basis with increasing frequency. We have already temporarily surpassed this level for individual months and indeed as averaged over the most recent 12-month period,” said WMO Deputy Secretary-General Ko Barrett.

She underscored, however, that temporary breaches do not mean that the 1.5 °C goal set in the Paris Agreement is permanently lost because it refers to long-term warming over decades.

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.

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 of such spikes in temperature – currently at 80 per cent – has been rising steadily since 2015, when such a probability was close to zero. For the years between 2017 and 2021, there was a 20 per cent chance of surpassing the limit, and this increased to a 66 per cent chance between 2023 and 2027.

Way off track

“Behind these statistics lies the bleak reality that we are way off track to meet the goals set in the Paris Agreement,” said Ms. Barrett.

She urged governments to do more to cut greenhouse gas emissions as an increasingly heavy price in terms of trillions of dollars in economic costs, millions of lives affected by more extreme weather and extensive damage to the environment and biodiversity would have to be paid otherwise.

Under the Paris Agreement, countries agreed to keep long-term global average surface temperature well below 2°C above pre-industrial levels and pursue efforts to limit it to 1.5°C by the end of this century. The scientific community has repeatedly warned that warming of more than 1.5°C risks unleashing far more severe climate change impacts and extreme weather, and every fraction of a degree of warming matters.

Devastating impacts

Even at current levels of global warming, there are already devastating climate consequences, such as more heatwaves, extreme rainfall events and droughts, reductions in ice sheets, sea ice and glaciers, accelerating sea level rise and ocean heating.

According to WMO’s report, for example, Arctic warming over the next five extended winters, from November to March, relative to the average of the 1991-2020 period is predicted to be more than three times as large as the warming in global mean temperature.

Predictions for March 2024-2028 suggest further reductions in sea ice concentration in the Barents Sea, Bering Sea and Sea of Okhotsk.