Sophisticated artificial intelligence (AI) algorithms have predicted that the world will be 1.5°C warmer than it was before the Industrial Revolution in the early 2030s – another climate change alarm bell to add to the cacophony that is already ringing.
And it’s built in, says the AI: No matter whether greenhouse gases rise or fall over the next decade, the 1.5°C rise can no longer be avoided. Remember that limiting the rise in temperatures to 1.5°C was the ambitious objective of the 2015 Paris Agreement.
The drastic measures initially proposed to reduce emissions and stay below 1.5°C of warming will now most likely be needed to avoid a 2°C rise, according to the authors of the new study. 2°C is considered the time when the consequences of global warming become significantly worse for life on the planet.
But we are already seeing a litany of climate impacts in the form of heatwaves, bushfires, floods and storms with just 1.1°C of global warming. Thus, limiting temperature increases as much as possible matters, because every fraction of a degree counts.
There’s more: the AI model shows that even if greenhouse gas emissions decline rapidly to net zero by 2076, there’s a 1 in 2 chance of reaching 2°C of warming by by 2054, and a 2 in 3 chance of reaching this goal between 2044 and 2065.
“Using an entirely new approach that leverages the current state of the climate system to make predictions about the future, we confirm that the world is on the verge of crossing the 1.5°C threshold,” says climatologist Noah Diffenbaugh of Stanford University in California.
“Our AI model is fully confident that enough warming has already occurred that 2°C is likely to be exceeded if reaching net zero emissions takes another half century.”
To reach these estimates, rather than using predictive climate models and global carbon budgets to calculate future warming, the researchers fed an AI known as a neural network a database of temperature changes that have occurred. already produced.
These neural networks use a large number of weighted nodes to spot patterns in existing data, patterns that can then be extrapolated into the future. In particular, the AI looked at recent temperature increases in specific locations compared to baseline data between 1951 and 1980.
To first test the accuracy of future estimates, the AI was asked to predict the current rise of 1.1°C above pre-industrial levels. Sure enough, it returned the correct year 2022, with a very likely range of 2017 to 2027.
“It was really the litmus test to see if the AI could predict when [of warming] that we know happened,” says Diffenbaugh. “We were quite skeptical about the effectiveness of this method until we saw this result.
“The fact that the AI has such high accuracy increases my confidence in its predictions of future warming.”
The AI prediction that the world will be one and a half degrees warmer by the early 2030s matches the findings of the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC ), that “the central estimate of crossing the 1.5°C threshold lies in the early 2030s”, adding further confidence in the accuracy of the AI.
There is still some uncertainty about when we might reach that 2°C rise, which is understandable when you’re trying to simulate an entire planet many years in the future. What we do know is that rising temperatures will trigger additional ‘tipping points’, creating a feedback loop of even greater warming.
This is why the 2°C level is considered so important by scientists. Its effects will be felt in crop failures, sea level rise, ecosystem collapse on land and seas, economic downturns and severe impacts on human health.
Zero emissions targets covering carbon dioxide, methane and other heat-trapping gases should be met by the middle of this century, the team suggests, to avoid exceeding 2°C of warming. Currently, most countries are aiming for somewhere between 2050 and 2070 to bring their emission levels down to zero.
“These net zero pledges are often focused on meeting the Paris Agreement’s 1.5°C target,” says Diffenbaugh.
“Our results suggest that these ambitious pledges may be necessary to avoid 2°C [warming].”
The research has been published in PNAS.