Scientists found that the world faces a significant risk of passing a crucial global warming threshold by mid-century.
The world is on the verge of crossing a critical climate threshold, indicating that time is running out to save the planet from the most disastrous effects of global warming, according to a new machine learning study.
The study, published this week, estimates that the planet could warm by 1.5 degrees Celsius above pre-industrial levels in a decade.
“We have very clear evidence of the impact on different ecosystems from the 1C of global warming that’s already happened,” said Stanford University climate scientist Noah Diffenbaugh, who co-authored the study published in the journal of Proceedings of the National Academy of Sciences.
“This new study, using a new method, adds to the evidence that we certainly will face continuing changes in climate that intensify the impacts we are already feeling,”he added.
This means that there is a “substantial possibility” that global temperature rises will exceed the 2-degree threshold by mid-century, even with significant global efforts to reduce planet-warming pollution.
Scientists have identified 1.5 degrees of warming as a critical tipping point beyond which the likelihood of extreme flooding, drought, wildfires, and food shortages will skyrocket.
Temperature rises over 2 degrees could bring catastrophic and potentially irreversible impacts, including pushing three billion people into “chronic water scarcity,” according to reports.
To conduct the study, scientists trained the AI system to analyse a wide range of global climate model simulations and asked it to determine timelines for given temperature thresholds.
The model found that even if emissions rapidly decline, there is a nearly 70% chance that the 2-degree threshold will be crossed between 2044 and 2065.
To test the AI’s prediction abilities, researchers entered historical measurements and asked the system to evaluate previously noted levels of heating.
The AI passed the test, correctly predicting both the 1.1C warming reached by 2022 and the patterns and pace observed in recent decades.
The study’s prediction matches some previous models. The Intergovernmental Panel on Climate Change (IPCC) estimated that the world would cross the 1.5-degree threshold “in the early 2030s” in a major report published in 2022.
While the IPCC predicts that global temperature rises will be less than 2 degrees Celsius by the end of the century in a low-emissions scenario, the AI study found more troubling results.
If emissions stay high, Diffenbaugh said, the AI predicted a 50% probability that 2 degrees will be reached before 2050.
Earlier estimates had put it closer to the end of the century.
There is “clear evidence that a half degree of global warming poses substantial risks for people and ecosystems. Hence, the greater the global warming, the greater the challenges for adaptation,” Diffenbaugh said.
Countries pledged in the 2015 Paris Climate Agreement to keep global warming well below 2 degrees Celsius, preferably 1.5 degrees Celsius, compared to pre-industrial levels.
While many net zero decarbonisation pledges and targets have been framed around keeping global warming to 1.5 degrees Celsius, Diffenbaugh added that AI predictions indicate that more efforts are needed to avoid reaching 2 degrees.
“Managing these risks effectively will require both greenhouse gas mitigation and adaptation,” he said. “We are not adapted to the global warming that’s already happened and we certainly are not adapted to what is certain to be more global warming in the future.”
