Robot “dolphins” are providing scientists with clues on exactly why ice caps are melting, and the early results are startling.

The 6-foot, 6-inch robotic gliders cost about $240,000 each and have built-in sensors that can track both temperature and salinity in the Weddell Sea near Antarctica, according to the Daily Mail. This “dolphin” has made a somewhat unnerving discovery: swirls of warm water are headed to the shallow regions of the Antarctic seas, which could further threaten the ice caps. The warm water is sent there by huge eddies the drive the heat, thawing coastal ice.

The findings, which have been published in the Nature Geoscience journal, could help scientists better predict the retreat of ice sheets, enabling them to refine climate models and determine how quickly global sea levels will rise from this warming.

Researchers had been operating the gliders remotely from in England, 10,000 miles away. The data was relayed back via satellite mobile phone technology for two months.

Scientists already knew that warmer water could be found deep in the Southern Ocean, but finding it in shallow water near Antarctica was a new revelation for researchers.

The research is part of an international study led by the California Institute of Technology. The gliders are powered by batteries can operate for months at a time, using small buoyancy adjustments to dive and surface.

The glider has allowed scientists to gain access to data they otherwise couldn’t due to the extreme temperatures of the region. It lets researchers build a more complete picture of underwater conditions through salinity, temperature, and oxygen measurements.

Three gliders were used in the study, and one was lost. Gliders are at risk because seawater can quickly freeze and trap the gliders. However, at such a small price tag, even with the lost glider it is a much cheaper expedition than spending $30,000 per day for a comparable trip using a ship in 2007, which collected less data.

Demand has been growing worldwide for unmanned underwater vehicles to conduct marine research in areas such as Antarctica, where human measurements are much more difficult.

Overall, there is a world market of about 800 gliders, according to manufacturer Kongsberg, which estimates it owns a quarter of that market.

Gliders are also used in the Arctic to note the migration of fish stocks north as temperatures rise.

The independence of the gliders and ability to rise and surface on their own for months at a time has led researchers to dub them, “mechanical dolphins.”

Scientists have also used about 3,600 Argo floats since 2000, which have been sitting adrift monitoring temperatures and sea salinity in the area, and NASA has sent unmanned aircraft to monitor sea-ice patterns from the air.