One of the world’s oldest and largest icebergs is stuck in an ocean vortex 800 miles from the Falklands.

The 1,500-square-mile floating mass of ice known as A23a was expected to drift to warmer waters and eventually dissolve.

The iceberg, twice the size of Greater London and three times that of New York City, is now stuck just off of the South Orkney Islands, north of Antarctica.

FITV spoke to Physical Oceanographer Dr J. Alexander Brearley from British Antarctic Survey to find out what causes this phenomenon.