Petermann Glacier

Europe’s Copernicus Sentinel-1 mission has captured a dramatic change at Petermann Glacier in northwest Greenland, where a 76 sq km section of the glacier’s floating ice tongue broke away on 4 August 2026. The event marks the glacier’s largest loss of floating ice since 2012 and the most significant calving event in the Arctic since 2020.

Background

The newly formed tabular iceberg, or ‘ice island’, covers an area about the same size of Manhattan and is estimated to be up to 150 metres thick. Sentinel-1 radar imagery captured on 3 August showed pronounced deterioration along the centreline of the ice tongue. By the following day, the vast ice island had detached from the eastern side of the glacier.

Monitoring

Because Sentinel-1 carries a radar, it can observe day and night and through cloud cover, making it particularly well-suited to monitoring remote Arctic glaciers. Using this Sentinel-1 radar imagery, an international team of researchers - partially funded through ESA’s FutureEO ARCTEX project - has been monitoring Petermann Glacier since 2019. The collaboration brings together scientists from the University of Ottawa in Canada, the Universities of Stirling, Lancaster and Leeds in the UK, and the Canadian Ice Service of Environment and Climate Change Canada.

Future Developments

Adam Garbo, a PhD student from the University of Ottawa, said, “Petermann Glacier has long been one of Greenland’s largest remaining ice tongues. We’ve anticipated this break for years, and seeing it finally happen is remarkable. It’s a powerful reminder of how quickly these systems can change.” The latest calving is unlikely to be the last major change at Petermann Glacier. Two further large ice islands, with estimated surface areas of approximately 97 and 87 sq km, could detach as existing rifts continue to propagate across the floating ice tongue.

The research team will continue to observe both Petermann Glacier and the newly calved iceberg using satellite imagery, aerial observations and tracking data, following its movement and fragmentation over time. These measurements will provide further insight into the behaviour of large Arctic ice islands and the processes shaping the evolution of Petermann Glacier. According to the source, https://www.esa.int/Applications/Observing_the_Earth/Copernicus/Sentinel-1/Sentinel-1_captures_major_ice_loss_from_Greenland_glacier, the calving also has practical implications for Arctic navigation and offshore operations. Environment and Climate Change Canada is monitoring the iceberg’s trajectory and assessing potential risks to shipping routes and infrastructure.