One of the largest glaciers in Antarctica is thinning four times faster than it was 10 years ago, according to research seen by the BBC.
A study of satellite measurements of Pine Island glacier in west Antarctica reveals the surface of the ice is now dropping at a rate of up to 16m a year.
Since 1994, the glacier has lowered by as much as 90m, which has serious implications for sea-level rise.
The work by British scientists appears in Geophysical Research Letters.
The team was led by Professor Duncan Wingham of University College London (UCL).
Calculations based on the rate of melting 15 years ago had suggested the glacier would last for 600 years. But the new data points to a lifespan for the vast ice stream of only another 100 years.
The BBC article is here.