> "What we’re particularly worried about is that this iceberg doesn’t have a very deep keel,” Tarling said. “So the amount of iceberg under the water isn’t as m

> "What we’re particularly worried about is that this iceberg doesn’t have a very deep keel,” Tarling said. “So the amount of iceberg under the water isn’t as much as you would normally expect for an iceberg like this.” If this thing is a massive ice cube floating in the sea then surely they know how much of it is under the water?