The Blood Falls of Antarctica

In one of the coldest, driest places on Earth, a strange sight stains the brilliant white ice of Antarctica with a deep crimson hue. Known as Blood Falls, this eerie phenomenon pours from the snout of Taylor Glacier into Lake Bonney in the McMurdo Dry Valleys. At first glance, it looks as if the glacier itself is bleeding.

The red flow was first observed in 1911 by the Australian geologist Griffith Taylor, who suggested the color came from red algae. Later research revealed a different explanation hidden within the ice.

For more than a million years, a pocket of briny water has been trapped beneath Taylor Glacier. This underground reservoir is sealed off from the surface, cut off from sunlight, oxygen, and the outside world. The water is about five times saltier than the ocean, preventing it from freezing despite the Antarctic cold.

As the glacier slowly shifts, some of this water escapes through cracks, oozing out in a striking blood-red stream. The color comes from iron in the water that oxidizes, essentially rusting, when it meets the air.