BBC: A river of ice in Greenland has become the fastest-flowing glacier currently known in the world, a study suggests.
In summer, the Jakobshavn Glacier - widely thought to have spawned the iceberg that sank the Titanic - is moving about four times faster than it was in the 1990s.
The Greenland Ice Sheet has seen record melting in recent years and would raise sea levels 6m were it all to vanish.
Details of the research are published in The Cryosphere journal.
Ian Joughin and Ben Smith of...