Right next to McMurdo in East Antarctica, the Dry Valleys are just a few kilometres from the Antarctic coast. The dry valleys are one of the strangest places on Earth. They are freezing cold, but high mountains and strong winds keep them mostly free of snow and ice. For a desert area, the dry valleys have many interesting phenomena to offer. Here you will find Lake Don Juan, with over 40% the most saline body of water on earth, and the Onyx River, with 32 kilometres the longest river in Antarctica. Hidden in the very back of Taylor Valley is another spectacular natural wonder, Blood Falls.
When geologists led by Griffith Taylor first discovered the frozen waterfall in 1911, they thought the red color came from red algae, but its true nature turned out to be much more spectacular. The red color that emerges is literally the rust of the glacier beneath its snow-covered crust.
In 2017, researchers finally figured out where the red discoloration came from. With radar measurements, they got to the bottom of Taylor Glacier and found out what was really going on.
The scientists made a groundbreaking discovery: they found hypersaline rivers (three times as salty as seawater) and reservoirs located 400 metres below the glacier that were able to retain their liquid form.
As it flows by, the glacier scrapes iron from the bedrock and mixes it with the brine. After being sealed in the glacier under high pressure for so long without sunlight or oxygen, the salt water turns blood red with the fresh air as it exits at Blood Falls.
The underground lakes are full of bacteria that extract energy from iron and sulphur. The existence of the Blood Falls ecosystem shows that life can exist under the most extreme conditions on Earth, even if it has had to do without sunlight or oxygen for several million years. This is of interest to astronomers who wonder if icy patches on Mars or Jupiter’s moon “Europa” could harbor similar life forms. In fact, it is possible that life on Earth evolved in the same way.
Heiner Kubny, PolarJournal