Powerful 'rivers in the sky' could cause Antarctic Peninsula's biggest ice shelf to collapse

When temperatures in Antarctica soared to 38 degrees Celsius above normal -- around 70 Fahrenheit -- in March, a teetering ice shelf the size of Los Angeles collapsed. Scientists don't know what role the extreme temperatures may have played in the event, but the heat rushed in through what's known as an atmospheric river, a long plume of moisture that transports warm air and water vapor from the tropics to other parts of the Earth.