Two studies show that Antarctica has been losing ice for longer than previously thought.
A team led by Shujie Wang at the University of Cincinnati in Ohio studied recently declassified images taken by US spy satellites. They found that glaciers feeding the Antarctic Peninsula's Larsen B Ice Shelf (pictured in 2000) were already accelerating towards the sea between 1963–79 and 1979–86, long before the shelf's spectacular collapse in 2002.
In separate work, Frazer Christie at the University of Edinburgh, UK, and his colleagues used scientific satellites to confirm that ice has been retreating along the coast of West Antarctica since at least 1975.
Geophys. Res. Lett. http://doi.org/bjm3; http://doi.org/bjm4 (2016)