Scientists now have their best view yet of where Antarctica is giving up ground to the ocean as some its biggest glaciers are eaten away from below by warm water.
Researchers using Europe's Cryosat radar spacecraft have traced the movement of grounding lines around the continent.
These are the places where the fronts of glaciers that flow from the land into the ocean start to lift and float.
The new study reveals an area of seafloor the size of Greater London that was previously in contact with ice is now free of it.
The report, which covers the period from 2010 to 2016, is published in the journal Nature Geoscience.
"What we're able to do now with Cryosat is put the behaviour of retreating glaciers in a much wider context," said Dr Hannes Konrad from the University of Leeds, UK.
"Our method for monitoring grounding lines requires a lot of data but it means you could now basically build a permanent service to monitor the state of the edges of the continent," he told BBC News.
