It’s not exactly news that Greenland and Antarctica are shedding ice at record rates.

But in 2016, an eyebrow-raising idea ricocheted through the scientific community: It was possible, the authors said, that a warmer planet could push the towering ice cliffs at the fringes of the Antarctic ice sheet to essentially self-destruct, collapsing like a set of dominoes.

What was extra shocking was just how fast the ice could retreat under this runaway scenario, leading to about three feet of sea level rise fed from Antarctica alone by 2100—much faster than previous estimates, which generally proposed increases of only a few centimeters by the end of the century.

But two new pieces of research, published Wednesday