A giant iceberg 140 square kilometres — 19km long by 8km wide — in size is drifting slowly north from Antarctica towards Western Australia.

The iceberg, known as B17B, was spotted by Australian Antarctic Division glaciologist Neal Young using satellite images taken by NASA and the European Space Agency.

Dr Young said the iceberg is about 1700 kilometres south-south-west of the West Australian coast and moving north/east with the ocean current and prevailing wind.

“B17B is a very significant one in that it has drifted so far north while still largely intact. It’s one of the biggest sighted at those latitudes, now 48.8º S and 107.5º E,” Dr Young said.

“As the water warms up the iceberg is thinning and slowly breaking up, resulting in hundreds more smaller icebergs in the area,” he said.

B17B calved from the eastern end of the Ross Ice Shelf nearly ten years ago, along with several other massive icebergs.

At first, most of these drifted out of the Ross Sea and began to head westwards round the Antarctic coastline, but many became trapped in ‘fast ice’ for several years in an area east of the Mertz Glacier.