The floating ice shelves that buttress Antarctica are less icy than we thought, it turns out. They’re filled with flowing water. New research published in the scientific journal Nature maps the extensive network of meltwater from Antarctica’s ice sheets and found that, contrary to previous understanding, lakes and rivers—even waterfalls—created by melting have been common for at least seven decades.
Two new papers analyze satellite imagery of Antarctica dating back to 1973 and aerial photography dating back to 1947 for evidence of meltwater. Warming oceans melt ice shelves around from the bottom up, while warming air temperatures melt them from the top down, creating pools and rivers of liquid water on the continent’s surface.
Researchers found that over the last 70 years, a system of meltwater drainage has transported water from the continent of Antarctica across the floating ice shelves that surround it, traveling up to 75 miles and creating ponds up to 50 miles long.
This isn’t great news for the stability of the ice shelf. Water is heavy, and the weight can cause the ice below these lakes to crack. As…