The truth about Antarctica's 'Blood Falls' finally oozes out of the ice

We may finally have an explanation for a red waterfall in Antarctica that has puzzled visitors and researchers since its discovery in 1911. Blood Falls may owe its rusty, bloody color to salty water that has been trapped under the Taylor glacier for more than 1 million years.

According to a new study published in the journal Glaciology, the color of the falls can be traced to iron-rich salty water, since the iron turns the brine red when it meets the air.

What was previously unknown is the presence of an intricate plumbing system within the glacier that is allowing the iron-rich water to flow out, giving the spot the appearance of a constant stream of blood.

The researchers at the University of Colorado and the University of Alaska used radio-echo sounding to transmit and receive electrical pulses on the glacier. This allowed them to view what was happening under the ice.

The study shows that liquid water can persist for long periods of time -- perhaps as long as a million years -- within frozen glaciers.

“While it sounds counterintuitive, water releases heat as it freezes, and that heat warms the surrounding colder ice,” said University of Alaska at Fairbanks glaciologist Erin Pettit, in a statement.

In addition, salty water has a lower freezing temperature, which also helps the liquid water stay that way.

“Taylor Glacier is now the coldest known glacier to have persistently flowing water,” Pettit said.

The persistent liquid water is even more remarkable considering that the Taylor Glacier is not at the top of the list of the bodies of ice that sea level rise specialists are worried about.

It has exhibited relatively limited surface melt and ends in the McMurdo Dry Valleys of East Antarctica, rather than the ocean, where it could be undermined by relatively mild ocean waters.