Big Pic: 820-Foot-High Tunnels Discovered Under Antarctic Ice
British Antarctic Survey Camp and Survey Plane Neil Ross This is the camp from which scientists discovered 820-foot-high channels underneath an ice shelf—a piece of ice jutting out into the ocean from land—in Antarctica. The tunnels are nearly as high as the Eiffel tower. Researchers from several universities in the U.K. and the British Antarctic Survey flew a plane over the Flichner-Ronne Ice Shelf in West Antarctica. (You can see the plane, a Twin Otter, parked at camp above.) Radar from the plane, as well as satellite photos, revealed that surface features on the ice corresponded to tunnels at the bottom of the ice. The placement of the channels suggests they were formed from meltwater flowing underneath the ice, over land, and into the ocean. That also suggests water underneath ice sheets pours out into the ocean in focused channels, sort...