Climate change affects Norway’s glaciers. Now new measurements establish how fat the largest of them is. And the researchers are surprised: – The ice is both thicker and thinner than we thought, and it was surprising to us that some areas had such thin ice, says Liss Marie Andreassen, glacier researcher at NVE. – Extensive work Several actors, including the University of Bergen and the University of Western Norway, participated in the project, which ran from 2018 to 2023. The measurements on the 458 square kilometer glacier were made with radar and both older and newer technology. The findings from the work were first discussed by the researcher. – It has been a lot of work to get so much of the Jostedalsbreen measured, says Andreassen. In total, measurements have been made along lines on the glacier, which are a total of 1,100 kilometers long. In addition, most glacier arms have been measured. Jostedalsbreen has 28 named glacier arms. SEVERAL ACTORS: Among others, the University of Bergen, the University of Western Norway and the University of Oslo were involved in the work. Photo: JOSTEIN AASEN / NVE The Jostedals glacier makes up 20 percent of Norway’s total glacier area. Due to the challenging terrain, the researchers have used both scooters and helicopters to get there. – In the innermost parts of Tunsbergdalsbreen, the ice is around 630 meters thick, while the ice in other places is thinner than we thought. For example, the ice is 50 meters thick at Lodalsbreen and less than 25 meters thick at Grensevarden, says Andreassen. RESULT: The graphic shows, among other things, where the ice is thinnest. Graphics: Mette Kusk Gillespie / The researcher son The glacier can be divided into three Mette Kusk Gillespie, associate professor at HVL and work package leader for JOSTICE, explains that the new measurements can help researchers to find out what will happen in the future. She says that they have found an area of thin ice, which binds the central part with the northern and southern parts. – This could lead to the Jostedalsbreen in the future splitting into three parts. A southern, central and northern part. In the border between the southern and central areas, the ice is less than 25 meters thick, and there the mountain begins to emerge in some places, says Gillespie. She adds that it is global warming that is causing the glacier to change. – Although there are variations from year to year, we can say on a general basis that the glaciers have become smaller since the year 2000. We expect this to continue. The consequences of this will mainly affect the local area. – For example, hydropower production and tourism may be affected by the changes. At the same time, we now have a better basis to say what will happen, and then we can take account of this going forward, says Gillespie. TO GET THERE: The researchers used both a scooter, a helicopter and their legs to help them make the measurements. Photo: JOSTEIN AASEN / NVE Can see what it looks like under the Jostedals glacier The measurements will also say something about what the landscape will look like after the Jostedals glacier, and by subtracting the thickness of the ice from the surface height, the researchers can find out what the landscape is like under the glacier. – We see depressions under the glacier, and these will fill with water, so when the ice melts, many new glacial lakes will emerge. These will cover part of the landscape which is now covered in ice, says Liss Marie Andreassen. EXTENSIVE WORK: The measurements were made between 2018 and 2023. Photo: JOSTEIN AASEN / NVE – Due to the melting of the glacier, there will be major changes in the future. In addition, we know how much volume there is in the ice, so then we can also simulate how the various glacier arms will change, she adds. When the “International Glacier Year” is marked next year, Andreassen and the rest of the researchers will present the results to a larger audience. But the results are out there, available to other researchers. – There are already several others in the team who are using what we have found to simulate what will happen to Jostedalsbreen in the future. So I think this will be used a lot by both Norwegian and international researchers, concludes Andreassen. Published 02.11.2024, at 08.04
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The glaciers in great change – have made surprising discoveries – news Vestland
