On Monday, the United Nations’ Intergovernmental Panel on Climate Change released a report that makes it unequivocally clear that human beings have locked in a measure of warming for the planet that will be extraordinarily difficult to endure. Warming of 1.5 degrees Celsius — roughly 2.7 degrees Fahrenheit, a threshold the IPCC advised the world’s nations to avoid crossing as recently as 2018 — is guaranteed to arrive within two short decades.

And more warming than that is very likely.

The planet has already warmed approximately 1.1 to 1.2 degrees C (1.98 to 2.16 degrees F). The climate impacts communities across the world have experienced this summer — extreme heat, catastrophic flooding, wildfires, and more — are due, in part, to that roughly one degree of warming. A 1.5 degree-warmed world means more summers like this one: more evacuees in California, more intense drought in the West, more blistering heat waves, more tropical storms that dump a season’s worth of water in 24 hours.

And yet, the IPCC report makes it clear that this is officially the best case scenario. We’ll be lucky if we get away with that little warming.

So let’s take a closer look at the best case. What does 1.5 degrees really look like?

It looks a lot like the world we’re living in now, but worse, says Daniel Swain, a climate scientist and science communicator at the University of California, Los Angeles. “A lot of folks have been kind of shocked by the events of this summer,” he told Grist. “1.5 degrees is still a significant increment of additional global warming beyond what we’ve already experienced. By the time we get there, the impacts will be all that more pronounced.”

Read the full article about the best-case climate scenario by Zoya Teirstein at Grist.