How large can a newly calved Antarctic tabular iceberg be?

Newly calved Antarctic tabular icebergs are massive, flat structures that typically range from several kilometres to tens of kilometres in diameter, with a thickness of 200–400 metres (660–1,320 feet) and a freeboard of 30–50 metres (100–160 feet). Their mass is often measured in the billions of tons.1

While typical dimensions are in the range of tens of kilometres, historical observations have recorded significantly larger examples. In 1927, an iceberg measured 180 km (110 miles) in length, and in 1956, an iceberg was sighted with an unconfirmed length of 335 km (210 miles) and a width of 100 km (60 miles). More recently, satellite measurements confirmed that iceberg B-15, which calved from the Ross Ice Shelf in 2000, had an initial length of 295 km (about 185 miles). These giant icebergs are primarily produced by the fracture of ice shelves fringing the Antarctic coastline.21