Colossal landforms recently found beneath the Antarctic ice sheet have surprised scientists. An international team found these eskers, or ridges of land similar to those left behind by ancient ice sheets, with satellite images and radar data – and it turns out they are far bigger than anything else like it on Earth. Some are as large as the Eiffel Tower and they might be contributing to Antarctic ice shelf thinning.
The ancient Scandinavian Ice Sheet of the Pleistocene epoch was one of the biggest glacial masses of that time, and left behind eskers for us to see. The ice sheet was around 9,800 feet thick, but for thousands of years landforms under the sheet mitigated precipitation and evaporation so ice would continue to cycle through the ocean, according to ScienceAlert.
Now scientists have uncovered evidence of the landforms beneath the Antarctic ice sheet. But these subglacial features are a staggering five times larger than the eskers left behind we can see today.
The scale of the eskers is shocking but they may also hold implications for the stability of the ice sheet. The Université libre de Bruxelles explained the “oversized sediment ridges actively shape the ice hundreds of kilometers downstream, by carving deep incisions at the bottom of the ice.” These gashes open up weak spots that are more susceptible to damage from warm ocean water. Researchers once thought ice shelves thinned only once they hit the ocean, but this new discovery means instability could impact the ice sheet even while it’s still on land. ScienceAlert pointed out we might not be able to halt the Antarctic ice sheet thinning, but a better understanding of the process could help us understand what will happen as the sheet thins.
Nature Communications published the team’s research online yesterday. Scientists from institutions in Belgium, Germany, the United Kingdom, and Norway contributed to the study.