The oceans may rise higher than we anticipated.
A study out Monday shows all the ice that’s been melting in Greenland and Antarctica may cause sea level rise to be way worse than we expect—like 6.5 feet by 2100. A government-funded study from last year anticipated a bit over 2 feet of rise this century, while the Intergovernmental Panel on Climate Change estimated about 3 feet in 2014, so the new estimate is a jump.
This research relies on expert judgment of future ice loss to calculate sea level rise in a worst-case scenario (which feels like the right way to go these days) where the world warms by 5 degrees Celsius this century. The authors found that, in this scenario, rising waters may displace up to 187 million people and inundate nearly 700,000 square miles, “including critical regions of food production,” as the study puts it.
Published in the Proceedings of the National Academy of Sciences, the study measures the sea level rise by weighing expert opinion on how much ice we’ll lose this century. They, then, combined that with past research on sea level rise to attempts to paint a clearer picture of the threat faced by coastal communities that will bear the burden of future ice melt. Cities like New York and Miami know that the waters surrounding them will eventually rise—and they’re trying to plan—but these new predictions may accelerate the timeline. This level of sea level rise “would clearly have profound consequences for humanity,” the authors write.
After 2100, the authors find that there’s much uncertainty about what’s to come. That’s because a lot of question marks remain about how the world’s ice sheets will fare in the near future. Greenland is losing ice much faster than it was in 1980, and that’s bad news for those of us who live near the water. If we’re gonna prepare, the authors argue we should get ready for the worst.