Your pee is melting Mount Everest

Climbers visiting Mount Everest are leaving behind more than just footprints. A new study shows that human waste is melting the mountain's glaciers.

Mount Everest is in trouble, and it is partly because of all the people visiting it. Every year, thousands of climbers head to the mountain’s base camp. When they stay there, they have to use the bathroom. Since there is no plumbing on the mountain, all that pee has to go somewhere. For a long time, it has just been dumped into the snow. Now, scientists say this is a big problem. All that human pee—plus fuel used for cooking and heating—is changing the snow. It acts like a dark blanket on top of the ice. Because it is dark, it soaks up the sun's heat instead of reflecting it away. This mak…