Scientists in Antarctica have, for the first time ever, drilled to the bottom of a glacier. If drilling through nearly a half-mile of ice to reach a mysterious world sounds like something out of 20,000 Leagues Under the Sea, you’re not too far off: In an article for, ÃÛèÖAPP journalist Douglas Fox calls this is a true pioneering effort, as no one’s ever been to the ground floor of a glacier before. But the real news is not how deep the researchers drilled; it’s how deeply disturbing their findings are.
The place where the drill team is stationed—a dense stretch of coastal ice shelf fed by a glacial river called the —was thought to be unaffected by global warming. But after drilling through the glacier, the scientists found a thin, gritty layer of pebbles and mud in the , instead of the finer sediments that it’s supposed to contain.
The grounding zone and the ice shelf are fed and created by glacial rivers. The zone forms a bridge underwater between the the grounded base of the glacier and the floating ice shelf, which eventually splinters into icebergs through erosion.
The anomaly in the debris might indicate a dramatic environmental change. Instead of being weighed down and slowly melting out of the glacier’s base, the coarser sediment the researchers found looks to have rapidly dropped to the seafloor. That could mean that the pace of melting is quickening in the grounding zone of this seemingly durable glacier.
Back on the ocean floor, the grounded glacier pushes against sediment, which creates a braking action that backs up the flow of the ice streams feeding it, and slows the movement of glacial ice into the sea. Fox says that this braking action is vital for slowing glacial melt. But warmer ocean currents are starting to melt ice at the grounding zone, which is reducing friction and making it easier for glaciers to thaw into the sea.
The findings are preliminary, since the sediment cores still need to be dated. The deposits could have plummeted just a few years ago, Fox writes, or they might be hundreds of years old. But they should help researchers figure out the rate of glacial melt for this ice shelf, and what impact it could have on the rise of global sea levels.
This evidence—the first of its kind—shows a major change taking effect in the glacial netherworld, and that these vast rivers of ice could be headed down an increasingly slippery slope.