Article content continued

“There is a lot of uncertainty about the future, our analysis does reflect that, but it also does reflect that the more optimistic scenarios that have been used in targets seem quite unlikely to occur,” said statistician Adrian Raftery of the University of Washington, Seattle. Raftery conducted the study, which was just published in Nature Climate Change, alongside colleagues at the University of California, Santa Barbara and Upstart Networks.

The second new study, meanwhile, takes a different approach, analyzing how much global warming the world has already committed to, since the warming due to some emissions has not yet arrived. Nonetheless, with the planet at a so-called energy imbalance, that warming is inevitably coming, and the study — conducted by Thorsten Mauritsen of the Max Planck Institute for Meteorology in Germany and Robert Pincus of the University of Colorado, Boulder — finds that it probably pushes us several slivers of a degree beyond where we are now.

The upshot is that we may already have firmly committed to 1.5 degrees Celsius of warming even if emissions were to stop immediately and entirely (which is not going to happen). One scenario presented in the study finds a 13-per-cent chance that 1.5 degrees is already baked in; another finds a 32-per-cent chance. And again, the margin for avoiding 2 degrees C narrows accordingly.

So what should we make of all of this?

On Monday I spoke with Glen Peters, a climate policy expert at the Center for International Climate Research in Oslo, about the two latest papers. Peters is a researcher who is on the record stating that he thinks there’s little chance of holding warming to 2 degrees Celsius unless we come up with so-called “negative emissions” technologies that allow us to actively withdraw carbon dioxide from the atmosphere later in the century.