Sept. 5 (UPI) -- The Antarctic iceberg A-68 has begun to spin. After a year-long standstill, the massive chunk of ice is on the move.
A-68 split from the Larsen C ice shelf last July. Scientists predicted the giant iceberg would begin to fragment shortly after its separation.
But over the last year, A-68 has remained mostly intact, anchored to the Bawden Ice Rise, a shallow seabed near the edge of the Larsen ice shelf. Scientists used satellite images to monitor the iceberg, but until now, there was little movement to report.
Now, just more than year after it first separated, A-68 is beginning to drift again.
"A-68 has started to swing northwards," scientists Mark Brandon reported in a blog update.
The right combination of weather conditions and ocean currents caused the iceberg to being to rotate counterclockwise.
The iceberg has lost a couple of sizable chunks, but it remains nearly as massive as it was 13 months ago.
Its size is roughly four times the size of the city of London, and its volume is twice that of Lake Erie. A-68 weighs more than 1 trillion metric tons.
The bottom of the iceberg is likely to leave large gashes in the seafloor's icy sediment -- gouges likely to be revealed by sonar surveys of the region scheduled for later this year.
Now that the iceberg is on the move, it's becoming more exposed to ocean currents and warmer waters. As a result, A-68 is likely to keep spinning and drifting away from the ice shelf from which it was calved.