This bulletin produced by the United Kingdom Met Office (the Met Office), which is WMO’s main center for this type of forecast, shows “with a high level of scientific competence” that we are getting measurably closer to the temporary achievement of the lower target of the Paris Agreement on climate change.
“The 1.5°C figure is not a random statistic,” said WMO Secretary-General Petteri Taalas, adding that “it indicates the point at which the effects of climate will become more and more harmful for populations, even for the entire planet”.
93% chance of having the hottest year on record
“There is a 93% chance that at least one year between 2022 and 2026 will become the hottest on record and knock 2016 out of first place,” the WMO argued.
Also, the probability that the five-year average for 2022-2026 will be higher than that of the last five years (2017-2021) is also 93%, according to the update.
The probability of temporarily exceeding 1.5°C has increased steadily since 2015, when it was close to zero. For the years between 2017 and 2021, the risk of overshoot was 10%. This probability has increased to almost 50% for the period 2022-2026.
“As long as we continue to emit greenhouse gases, temperatures will continue to rise. At the same time, our oceans will continue to warm and acidify, sea ice and glaciers will continue to melt, sea levels will continue to rise, and our weather will become more extreme,” explained the head of OMM.
Mr Taalas added that “the warming of the Arctic is disproportionate and what happens in this region affects us all”.
The objectives of the Paris Agreement
The Paris Agreement sets long-term goals to guide all nations to substantially reduce global greenhouse gas emissions in order to limit global temperature increase to 2°C this century, while continuing efforts to further limit this increase to 1.5°C.
According to the Intergovernmental Panel on Climate Change (IPCC), climate-related risks to natural and human systems are higher at a global warming of 1.5°C than at present, but lower than at 2°C.
“Our latest climate predictions show that the continued rise in global temperature will continue, with an equal chance that one of the years between 2022 and 2026 will exceed 1.5°C above pre-industrial levels,” said Dr Leon Hermanson. , from the Met Office, who led the report.
“A single year of overshooting 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,” said the scientist.
A single year of exceeding 1.5°C does not mean that we have crossed the emblematic threshold of the Paris Agreement
In 2021, the global average temperature was 1.1°C above the pre-industrial baseline, according to the WMO’s interim report on the state of the global climate. The final report on the state of the global climate for 2021 will be published on May 18.
Other factors, back-to-back episodes of La Niña in early and late 2021 have had a cooling effect on global temperatures, but this effect is only temporary and does not reverse the global warming trend to long term. Any development of an El Niño event would immediately fuel temperatures, as was the case in 2016, which is so far the hottest year on record.
This annual update draws on the expertise of internationally renowned climatologists and the best forecasting systems from major climate centers around the world to produce actionable information for decision makers.
The main conclusions of the annual update
The conclusions of the annual update as to the expected temperatures and precipitation are as follows:
- The global mean annual near-surface temperature for each year between 2022 and 2026 is projected to be 1.1°C to 1.7°C above pre-industrial levels (the average over the years 1850-1900).
- The probability of global surface temperature exceeding pre-industrial levels by 1.5°C in at least one year between 2022 and 2026 is about as high as no probability (48%). There is only a small probability (10%) that the five-year average exceeds this threshold.
- The probability that at least one year between 2022 and 2026 will exceed the hottest year on record (2016) is 93%. The probability that the five-year average of 2022-2026 will be higher than that of the last five years (2017-2021) is also 93%.
- The Arctic temperature anomaly, relative to the 1991-2020 average, is projected to be more than three times the global average anomaly when averaged over the next five extended Northern Hemisphere winters.
- There is no signal for the El Niño Southern Oscillation for December-February 2022/23, but the Southern Oscillation Index is expected to be positive in 2022.
- Precipitation patterns forecast for 2022 relative to the 1991-2020 average suggest an increased likelihood of drier conditions over southwestern Europe and southwestern North America, and wetter conditions over northern Europe, the Sahel, northeastern Brazil and Australia.
- Precipitation patterns forecast for the 2022-2026 May-September average, compared to the 1991-2020 average, suggest an increased likelihood of wetter conditions in the Sahel, northern Europe, Alaska and northern of Siberia, and drier conditions on the Amazon.
- Precipitation patterns projected for the November-March average of 2022/23-2026/27, relative to the 1991-2020 average, suggest increased precipitation in the tropics and reduced precipitation in the subtropics, consistent with models. expected from global warming.