The year in which the world will first cross the 1.5°C global heating limit set by international governments is fast approaching, according to a new forecast.
The chance of one of the next five years exceeding the limit is now 50%, scientists led by the UK Met Office have found. As late as 2015, there was no way that would happen in the next five years. But that jumped to 20% in 2020 and 40% in 2021. The global average temperature was 1.1°C above pre-industrial levels in 2021.
There is also almost certainty – 93% – that by 2026 a year will be the warmest on record, beating 2016, when a natural El Niño weather event supercharged temperatures. It is also almost certain that the average temperature for the next five years will be higher than that of the past five years, as the climate crisis intensifies.
“The 1.5°C figure is not a random statistic. Rather, it is an indicator of the point at which climate impacts will become increasingly harmful to people and even to the entire planet,” said Professor Petteri Taalas, head of the World Meteorological Organization, which published the new report. .
“As long as we continue to emit greenhouse gases, temperatures will continue to rise,” Taalas said. “As well, our oceans will continue to warm and acidify, sea ice and glaciers will continue to melt, sea levels will continue to rise, and our climate will become more extreme.”
Natural weather cycles can cause global temperatures to rise or fall. But the Paris Agreement obliges nations to keep the underlying, human-driven rise well below 2C, as well as to continue efforts to limit the rise to 1.5C. Scientists around the world warned in 2018 that 1.5°C of global warming would have serious consequences for billions of people.
“A single year of overshoot above 1.5°C does not mean that we have crossed the emblematic threshold of the Paris Agreement, but it does reveal that we are getting closer and closer to a situation where 1, 5°C could be exceeded for an extended period,” Dr Leon Hermanson told the Met Office.
“The possibility of exceeding the 1.5C threshold, even for just a year, is worrying,” said Dr Andrew King, from the University of Melbourne. “Our greenhouse gas emissions are still at near record highs and until we get our emissions down to zero we will continue to see global warming. Rapid and drastic cuts in emissions are urgently needed. .
“To really go beyond the [Paris] goal, we should be above 1.5C even in a ‘normal’ year” unaffected by natural climate variations, said Professor Steven Sherwood of the University of New South Wales. “But the report reminds us that we are getting uncomfortably close to that goal.”
The annual forecast leverages the best forecasting systems from climate centers around the world to produce practical information for decision makers. It found a higher probability of rain in 2022 compared to the past 30-year average in northern Europe, the Sahel, northeast Brazil and Australia, while drier conditions than d habit are predicted for southwestern Europe and southwestern North America. .
Professor Taalas also warned of particularly rapid warming at the North Pole: “Arctic warming is disproportionately high and what happens in the Arctic affects us all. Shrinking sea ice and its repercussions have been linked to extreme weather events in Europe, North America and Asia, including heat waves, floods and even snowstorms.
Forecasts indicate that the temperature increase in the Arctic will be three times higher than the global average over the next five years.