An one-trillion-tonne iceberg, more than six times the size of Auckland, has broken away from Antarctica and is now adrift in the Weddell sea. At roughly 6,000 square kilometres, it's one of the biggest icebergs ever recorded, to break away from the continent. An American satellite observed the iceberg while passing over a region known as the Larsen C Ice Shelf, near the south Atlantic. It had been expected to break off, for more than a decade now, but the cracking off the shelf had been accelerating rapidly in the past three years. Kathryn Ryan speaks with the director of Victoria University's Antarctic Research Centre, Andrew Mackintosh.