Thank you, Eric Holthaus, for your entertaining, mildly sensational climate change coverage at Slate.

In a study released Wednesday, a new estimate of how much Antarctic ice would melt in a warmer world nearly doubles previous projections of sea level rise by the end of the century. And it might be even worse than that: The study did not explore the true worst-case scenario, and its lead author said the work is still incomplete. Taken together with recent results from other research teams—most notably James Hansen’s, just last week—it’s increasingly clear that consensus projections of near-term sea level rise, about three feet in the next 85 years, are likely an underestimate.

The latest information comes via a breakthrough in simulating the behavior of Antarctica’s vast and complex network of glaciers and ice shelves. That’s brought a more complete understanding of how warmer air temperatures—projected to surpass those regularly experienced on Earth at any point during at least the last few million years—are affecting the sea level. At the same time, the study provides new certainty that—should the world act immediately to curb carbon emissions at a scale far beyond current efforts—virtually all Antarctic ice melt could be avoided.