Tidal action on the underside of the Thwaites Glacier in the Antarctic will “inexorably” accelerate melting this century, according to new research by British and American scientists. The researchers warn the faster melting could destabilize the entire West Antarctic ice sheet, leading to its eventual collapse. The massive glacier—which is roughly the size of Florida—is of particular interest to scientists because of the rapid speed at which it is changing and the impact its loss would have on sea levels (the reason for its “Doomsday” moniker).