Grand Canyon-Sized Rift Speeding Antarctic Ice Melt
A rift in the Antarctic rock as deep as the Grand Canyon is increasing ice melt from the continent, researchers say. A U.K. team found the Ferrigno rift using ice-penetrating radar, and showed it to be about 1 mile deep. Antarctica is home to a geological rift system where new crust is being formed, meaning the eastern and western halves of the continent are slowly separating. The team writes in the journal Nature that the canyon is bringing more warm sea water to the ice sheet, hastening melt.
Ice loss from West Antarctica is believed to contribute about 10% to global sea level rise. But how the West Antarctic and Greenland ice sheets respond to warmer temperatures is the biggest unknown by far in trying to predict how fast the waters will rise over the coming century and beyond.