On the east side of Antarctica, there’s a glacier called Taylor Glacier, and for over a century, it’s been doing something odd. Every so often, a rush of what looks like blood spills out from its base and stains the ice surrounding it. The phenomenon was first spotted back in 1911. Not long after, the glacier picked up the name “Blood Falls.”
Now, scientists have long known the basics of why the glacier does what it does. Beneath the glacier, there’s ancient saltwater — known as brine — that’s loaded with iron. You can guess what happens then. When that saltwater reaches the surface and hits open air, the iron reacts with oxygen, turning rust-red within minutes. That part has been understood for a while now.
What hadn’t been understood was what actually triggers those bursts. Why does the brine suddenly decide to escape, and what’s going on beneath the ice when it does? A new study published in the journal Antarctic Science now explains. It caught the whole event in action for the first time and explained it properly. The answer seems to involve the glacier itself physically sinking. Let’s dive in.
What the new research found
The study’s findings actually come from a lucky alignment. Back in September 2018, a GPS tracker on the surface of Taylor Glacier happened to be recording alongside a camera pointed at Blood Falls and a temperature sensor in the nearby Lake Bonney. Luck is always welcome in a field where studies sometimes depend on things like a lost robot rescued from Antarctic ice carrying crucial data.
Anyway, all three instruments recorded something unusual at the same time. The glacier’s surface sank and slowed down, the camera caught fresh red discharge at Blood Falls, and the lake sensor detected a cold dip at exactly the depth where brine would settle. Peter T. Doran, a geoscientist at Louisiana State University, saw the opportunity and connected the dots across all three of those datasets with a group of researchers. It may be hard to see how these events are , but Doran’s team is here to explain.
They’ve explained in their paper that the weight of the glacier traps salty water beneath it, and over time, that pressure just keeps building. The glacier can’t hold that squeeze forever, though. Slow movement of the ice eventually pushes the brine toward cracks, where it escapes in pulses — some of it flows up to the surface at Blood Falls, and some of it seeps quietly into the lake. Once that water drains away, there’s less pressure propping up the ice from below, so the glacier settles downward and loses speed. Think of it like letting air out of a cushion — the thing sitting on top sags. Only here, the cushion is ancient brine, and the thing on top is a glacier.
This isn’t the first attempt at an explanation
This isn’t the first time researchers have tried to get the Blood Falls phenomenon explained. For instance, a 2017 study led by Jessica Badgeley at Colorado College used radar to actually map those pathways inside the glacier that the brine travels through before reaching the surface. That was a pretty big deal because it showed liquid water could persist in extremely cold ice – Taylor Glacier’s core sits at around 0°F — which was something scientists didn’t think was possible. The salt content of the water lowers its freezing point enough to keep it moving, and the heat released by freezing at the edges apparently warms the surrounding ice just enough to keep these channels open.
Then, in 2023, researchers at Johns Hopkins found that the red color specifically comes from tiny iron-rich nanospheres rather than traditional minerals. Those had gone undetected because they’re not crystalline, so the earlier detection methods that were being used simply missed them. Now, the new study builds on all of this.
