A comparison of the reliability of climate models—based on their ability to replicate present-day conditions on Earth—finds that the most accurate also imply the bleakest forecast for humanity and most other living creatures, an article in the journal Nature reports.
The statistical study, by Patrick Brown and Ken Caldeira of the Carnegie Institution for Science in Stanford, California, examined climate change simulations that model the evolution of the atmosphere and behaviour of the oceans in mathematical equations, based on decades of research in nature.
“The researchers then looked at what the models that best captured current conditions high in the atmosphere predicted was coming,” the outlet writes. What they found was that “those models generally predicted a higher level of warming than models that did not capture these conditions as well. Overall, the change amounted to bumping up the projected warming by about 15%.”
“We know enough about the climate system that it doesn’t necessarily make sense to throw all the models in a pool and say, we’re blind to which models might be good and which might be bad,” Brown told the Washington Post.
The group’s findings lend sombre weight to the warning last August from University of Washington climate scientist Adrian Raftery, whose own climate model gives humanity only a 5% chance of keeping average global warming below 2.0°C by 2100 based on today’s climate trajectories. “We’re closer to the margin than we think,” he said at the time. “We have very little time left. The public should be very concerned.”