Larsen, cracked (video)

April 20, 2017 – The Copernicus Sentinel-1 satellite mission is monitoring the growing crack in Antarctica’s Larsen-C ice shelf. When the ice shelf breaks off or ‘calves’, it will create one of the largest icebergs ever recorded – but exactly how long this will take is difficult to predict.

This animation demonstrates how scientists analyse radar data from Sentinel-1 to monitor the crack. This includes combining radar images to create an ‘interferogram’.

Polar scientist Anna Hogg said: “We can measure the iceberg crack propagation much more accurately when using the precise surface deformation information from an interferogram like this, rather than the amplitude – or black and white – image alone where the crack may not always be visible.”

When the ice shelf calves this iceberg it will be one of the largest ever recorded – but exactly how long this will take is difficult to predict. The sensitivity of ice shelves to climate change has already been observed on the neighbouring Larsen-A and Larsen-B ice shelves, both of which collapsed in 1995 and 2002, respectively.

These ice shelves are important because they act as buttresses, holding back the ice that flows towards the sea.

The Copernicus Sentinel-1 two-satellite constellation is indispensable for discovering and monitoring events like these because it delivers radar images every six days, even when Antarctica is shrouded in darkness for several months of the year.