Hidden ice river flows with life
New Zealand scientists have found life thriving in one of Earth’s most hostile environments – a thick sheet of floating ice off the edge of Antarctica. Professor Huw Horgan from the Victoria University of Wellington was studying satellite images of the enormous Ross Ice Shelf when he noticed a groove running across its surface. Its shape and where it was suggested that it was following the line of what might be a river flowing along a tunnel in the ice below.
Experts have suspected for a long time that there are freshwater rivers and lakes under the Antarctic ice, but until now only those on the land of the continent itself (rather than out in the sea ice) have been investigated. A team of New Zealand researchers working on the ice shelf set out to find the shallow dip in the smooth icy landscape, then used a jet of hot water to melt their way down through 500 metres of ice. They finally reached an underground cave, which had a river running through it. When they lowered a camera into the cavern they saw that the water was alive with countless tiny, shrimp-like creatures called amphipods.
Professor Craig Stevens said his team was “jumping up and down” with excitement over their discovery, adding, “Having all those animals swimming around our equipment means that there’s clearly an important ecosystem there.” In other words, the thriving amphipods can find food to eat, and there may even be things that prey on them.
Shortly after reaching the cavern in January
2022, the team were able to see how the river’s flow was affected by waves that spread out from a huge volcanic eruption in the South Pacific islands of Tonga. Stevens said seeing the effect of an eruption thousands of miles away was “quite remarkable”. He added, “It is also a reminder about just how connected our whole planet is.”