Mainland Europe’s largest glacier may be halved by 2100

A new study predicts how the Jostedalsbreen glacier will change in a warmer climate, using computer models to simulate future melting.

Group of skiers with rucksacks crossing a vast snowy glacier in mist and sun

The 62-kilometre ski route 'Josten på langs' across the Jostedalsbreen glacier is under threat. As the glacier splits into smaller parts, the trip is unlikely to be the same.

(Photo: Liss M. Andreassen)

Gunn Kristin Tjoflot Gunn Kristin Tjoflot Gunn Kristin Tjoflot SENIOR ADVISER

Presented by: Presented by: Presented by: University of Oslo

Published 3 February 2026 - 00:01

The largest glacier in mainland Europe, Jostedalsbreen, is located in Western Norway.

The Jostedalsbreen glacier covers an area of 458 square kilometres and is an ice cap – a large, thick ice mass with a high, relatively flat interior, where ice flows outwards in all directions. The ice cap is part of Jostedalsbreen National Park, established in 1991.

In a new study, researchers show what will happen to Jostedalsbreen in a warmer climate.

They simulated the glacier’s future up to the years 2100 and 2300 using an advanced computer model that calculated how the ice will melt and flow under different greenhouse-gas emission scenarios.

Jostedalsbreen ice cap is characterised by extensive flat areas in its interior and multiple outlet glaciers – here illustrated by Opptaksbreen.

Temperatures are rising, glaciers are retreating

Annonse

The report Climate in Norway shows that the temperature in Norway increased by about 1.4°C between 1901 and 2024. Most of this increase – roughly 1°C – happened in the past 50 to 60 years.

The researchers’ new glacier projections indicate that Jostedalsbreen will lose a moderate amount of ice up to about 2050, followed by a much faster decline. This is based on future temperature increases under moderate greenhouse gas emissions.

"This will result in the glacier fragmenting into several smaller units and in outlet glaciers retreating by several kilometres. These glacier arms will be far less visible and accessible from the nearby valleys," says Henning Åkesson, a researcher at the University of Oslo.

Jostedalsbreen in 2019 compared to 2100 under a moderately high emissions scenario. The glacier will split into a number of smaller parts and its outlet glaciers retreat by several kilometres.

The calculations also show that if the glacier were to disappear completely, today’s climate would not allow it to grow back to its current size.

Small glaciers are melting away, and the largest are retreating

'The climate is changing, Norway’s glaciers are struggling in the heat, and this will continue. Our smallest glaciers are already disappearing. When the ice retreats and the landscape changes, future glacier hikers or those attempting the popular spring ski traverse 'Josten på langs' will have to go much farther,' the researchers write in a popular‑science article on forskersonen.no (link in Norwegian).

“But it will take longer for Jostedalsbreen to disappear than for the smaller glaciers. This is a large plateau glacier covering an area the size of Oslo municipality, and the ice is up to 630 metres thick, with an average thickness of around 150 metres,” says Liss Andreassen, a researcher at the Norwegian Water Resources and Energy Directorate (NVE).

The history of Jostedalsbreen

Was Jostedalsbreen part of the ice sheet covering northern Europe during the last Ice Age?

“Jostedalsbreen is believed to have existed here since about 6,000 years ago, when the climate gradually cooled. Most likely all, or nearly all, Norwegian glaciers melted away during a warm period roughly 5,000 to 7,000 years ago," says Åkesson.

He says that Norwegian glaciers are therefore not remnants of the large ice sheet from the last Ice Age, even though it's easy to think so.

What could happen to Jostedalsbreen after 2100?

Åkesson explains that the scenario in which Jostedalsbreen is halved by the end of this century corresponds to what we can expect if countries follow their current emission reduction pledges.

“But if those cuts fail and emissions continue to rise, the glacier will have only just over one third of today’s ice volume by 2100,” he says.

Annonse

The researchers warn that this trend will continue beyond 2100. Under high emissions, Jostedalsbreen could lose 99 per cent of its current volume by 2300.

According to the researchers, future emissions pathways will therefore determine whether coming generations will get to experience Jostedalsbreen.

Reference:

Åkesson et al. Recent history and future demise of Jostedalsbreen, the largest ice cap in mainland Europe, The Cryosphere, 2025. DOI: 10.5194/tc-19-5871-2025

About the research:

The work behind this study was funded by the Research Council of Norway under the JOSTICE project (grant no. 302458).

The study was a collaboration between Norwegian researchers at the University of Oslo, University of Bergen, the Norwegian Water Resources and Energy Directorate, and Western Norway University of Applied Sciences.