Scientists were surprised to discover that there is a lot of geothermal heating underneath the West Antarctic Ice Sheet — much more so than they had anticipated.

Researchers at the University of California Santa Cruz measured heat in the sediments underneath the ice sheet to make the findings, and they found that the flow of heat that is traveling upward from geothermal sources up underneath the base of the ice is much higher than expected, according to a UPI report.

Andrew Fisher, a professor of Earth and planetary sciences at the university, said in a statement that the ice sheet “developed and evolved with the geothermal heat flux coming up from below,” which could explain the unstable nature of the ice sheet, according to the report. Add that to the effects of global warming, and it could explain a sudden loss in ice.

If the findings are correct, it would explain the large subglacial lakes, as well as the strong flow of glacial streams on the ice sheet. This flow of water only increases that rate of ice loss, scientists believe.

The researchers cautioned that the findings were made only at one spot underneath the ice sheet, so it’s possible this is just a localized phenomenon.

There are complex systems at work when it comes to polar ice sheets, and researchers are trying to understand better how they work. This research may further bolster that effort. By further refining their knowledge of how these ice sheets operate, scientists could better hone in on how quickly ice streams flow, how much ice is melting and how fast, and what the impact is on sea levels.

The study was published in the journal Science Advances.