For the past few years, climatologists have been telling people three things: yes, the world is warming. Yes, human-contributed carbon dioxide is contributing to this warming. And the best-case scenario is an average increase of 2 degrees Celsius, which might not sound like a lot, but has the potential to wreak havoc on some ecosystems.
But now, the International Energy Agency is warning that a 2 degree increase is too optimistic, and the world’s current path is more likely to result in an increase of 3.6 and 5.3 degrees Celsius. The agency is recommending governments adopt four new policies to try to slow the warming, and hold it to 2 degrees Celsius. They’re calling this the “4-for-2°C scenario,” and say it would lower emissions with proven technologies without harming economic growth.