Imagine Antarctica. What are you thinking about? Maybe snow, wind and dramatic ice formations? Most of us have an idea of what the landscape at the South Pole looks like. At least on the surface. But under the ice there is a world of its own. New research sheds light on what lies beneath the ice. Photo: Eivind Molde / news A hidden system in the ice It has been many decades since scientists discovered something that made them wonder. Far under the ice in Antarctica, there are large accumulations of water – a form of hidden lakes. At first, scientists thought these lakes were separate. Then they began to wonder if there might be some kind of connection between them. Now they have found new answers. Using aircraft radar and models that simulate water currents, experts have mapped what is going on in the ice. And the result is startling. The researchers discovered a large network of rivers. These rivers connect the lakes together. – We are beginning to understand that there are whole systems down there, says glacier researcher Martin Siegert at Imperial College in London in a press release. One of the rivers discovered is 460 kilometers long. It is longer than the distance between Oslo and Trondheim. Now the researchers believe that the hidden rivers can help us find answers to important climate questions. The river is hidden far below the surface. Photo: Svein Østerhus at NORCE Living his own life Tore Hattermann is a researcher at the Norwegian Polar Institute in Tromsø. He says they have had assumptions that there could be such systems under the ice. Now it is confirmed. – It is quite unique, he says to news. Hattermann believes the findings can help us understand how the ice in Antarctica melts. It can also provide answers to how quickly the process takes place. There is a difference in how the ice at the various poles melts. In summer, the temperature of the Greenland ice sheet in the Arctic can become so high that the ice melts on the surface. This is not the case in Antarctica, explains the researcher. There you have the unknown network of rivers under the ice, which live their own lives. If it gets warmer in the atmosphere, the ice can start to melt on the surface. Then the rivers that flow in the depths will become more powerful. – Both parts will intensify the melting. It’s something we have to keep a close eye on, says Hattermann. Tore Hattermann is a marine researcher at the Norwegian Polar Institute. He thinks that the new research findings are exciting. Photo: Jörg Brozek The missing piece The researchers behind the study are not sure how the hidden rivers will affect the melting of ice in Antarctica. But they have a theory: When the water flows through the river, it can contribute to the melting of the surrounding ice. As more and more water flows through this channel, the melting will escalate. The water can also help to destabilize the ice, so that it dissolves and floats into the sea. Then the sea level rises. This in turn can have major consequences for the climate. To be able to estimate how much the sea will rise, it is important to take into account the contribution of such rivers under the ice, explains Tore Hattermann. The researchers behind the study also hope that the river they discovered on the aircraft radar can provide new answers. – We know which areas in Antarctica are losing ice, and how much. But we don’t necessarily know why, says Dr. Christine Dow from the University of Waterloo. She believes the discovery could be the missing piece of the puzzle. How can melting ice in Antarctica affect sea level? Studies have shown a strong connection between temperature in Antarctica and global sea level. The contribution from ice melting in Antarctica is very decisive for the assessment of a possible future rise in sea level. A collapse of the Antarctic ice masses that are in contact with the sea – where the bedrock lies below sea level – could in the short term cause a significantly greater rise in sea level than estimated. Source: Norwegian Polar Institute
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An unknown river can provide new knowledge about ice melting in Antarctica and sea level rise – news Trøndelag
