The Earth Sciences Department of the Barcelona Supercomputing Center (BSC) has been one of the climate prediction groups that have contributed to the new Global Annual to Decadal Climate Update, issued this week by the World Meteorological Organization (WMO). The study concludes that there is a 50:50 chance of the annual average global temperature temporarily reaching 1.5 °C above the pre-industrial level for at least one of the next five years – and the likelihood is increasing with time.
The WMO climate update, led and produced by the United Kingdom’s Met Office as the host of the Lead Centre for Annual-to-Decadal Climate Prediction, collects and combines forecasts from leading climate prediction groups around the world, which enables a higher quality product than what can be obtained from any single source. The main goal is to produce actionable information for decision-makers vulnerable to climate variations within the next five years.
According to the study, there is a 93% likelihood of at least one year between 2022-2026 becoming the warmest on record and debunking 2016 from the top ranking. The chance of the five-year average for 2022-2026 being higher than the last five years (2017-2021) is also 93%.
The chance of temporarily exceeding 1.5°C has risen steadily since 2015, when it was close to zero. For the years between 2017 and 2021, there was a 10% chance of exceedance. That probability has increased to nearly 50% for the 2022-2026 period.
With a high level of confidence, the study shows that we are getting closer to temporarily reaching the lower target of the Paris Agreement on Climate Change. The Paris Agreement sets long-term goals to guide all nations to substantially reduce global greenhouse gas emissions to limit the global temperature increase at the end of this century to 2 °C, while pursuing efforts to limit the increase even further to 1.5 °C.
“It is still possible to meet the most ambitious goals of the Paris Agreement, although this requires massive reductions in greenhouse gas emissions, decreasing among other things the use of fossil fuels to zero in the immediate future, which does not seem to be on the table at the moment. We need to put in place efforts that should have already started long time ago,” said Francisco Doblas, director at the Earth Sciences Department of the BSC and ICREA professor.
Doblas pointed out that the results of the WMO climate update are consistent with the longer-term warming estimates that are included in the latest assessment of the Intergovernmental Panel on Climate Change (IPCC), in the preparation of which Prof Doblas took part. "We are clearly not yet on the right track," warned the BSC Earth Sciences Department’s director.
The BSC-CNS provides the Lead Centre with global decadal climate predictions with its global climate model, EC-Earth. The BSC-CNS is one of the five global production centres designated by WMO.
The findings of the WMO annual update include:
- The annual mean global near-surface temperature for each year between 2022 and 2026 is predicted to be between 1.1 °C and 1.7 °C higher than preindustrial levels (the average over the years 1850-1900).
- The chance of global near-surface temperature exceeding 1.5 °C above preindustrial levels at least one year between 2022 and 2026 is about as likely as not (48%). There is only a small chance (10%) of the five-year mean exceeding this threshold.
- The chance of at least one year between 2022 and 2026 exceeding the warmest year on record, 2016, is 93%. The chance of the five-year mean for 2022-2026 being higher than the last five years (2017-2021) is also 93%.
- The Arctic temperature anomaly, compared to the 1991-2020 average, is predicted to be more than three times as large as the global mean anomaly when averaged over the next five northern hemisphere extended winters.
- There is no signal for the El Niño Southern Oscillation for December-February 2022/23, but the Southern Oscillation index is predicted to be positive in 2022.
- Predicted precipitation patterns for 2022 compared to the 1991-2020 average suggest an increased chance of drier conditions over southwestern Europe and southwestern North America, and wetter conditions in northern Europe, the Sahel, north-east Brazil, and Australia.
- Predicted precipitation patterns for the May to September 2022-2026 average, compared to the 1991-2020 average, suggest an increased chance of wetter conditions in the Sahel, northern Europe, Alaska and northern Siberia, and drier conditions over the Amazon.
- Predicted precipitation patterns for the November to March 2022/23-2026/27 average, compared to the 1991-2020 average, suggest increased precipitation in the tropics and reduced precipitation in the subtropics, consistent with the patterns expected from climate warming.