Giant iceberg off Australia breaking up

A massive iceberg edging slowly toward Australia's southwestern coast is breaking up into hundreds of smaller icebergs as it drifts into warmer waters, creating potentially hazardous conditions for ships trying to navigate the region, a scientist said Tuesday.

The iceberg, known as B17B, was spotted last week on satellite imaging about 1,700 kilometres off Western Australia state, prompting Australia's Bureau of Meteorology to issue a shipping alert.

Since then, it has shrunk from 140 square kilometres to 115 square kilometres, or around 18 kilometres long and eight kilometres wide, said glaciologist Neal Young of the Australian Antarctic Division.

The iceberg has broken up into hundreds of smaller icebergs, some up to several kilometres wide, and spread over more than 1,000 kilometres of ocean, he said.

"I expect it to dissipate," Young said. But exactly when, he added, is anyone's guess.

The iceberg is one of several that split off in Antarctica in 2000 when parts of two major ice shelves — the Ross Sea Ice Shelf and Ronne Ice Shelf — fractured.

New Zealand issued a shipping alert last month after authorities spotted a flotilla of icebergs heading toward South Island. Those icebergs have since moved east, away from New Zealand.

Icebergs are routinely sloughed off as part of the natural development of ice shelves.

B17B is expected to continue moving east.