Scientists gave it the romantic name of PII-2012 and watched it begin to drift slowly into the Nares Strait, which separates Greenland from Canada. Then it began to break up, spawning several smaller ice islands.

The birth of PII-2012 was no isolated event. The Petermann Glacier had lost a much larger chunk in 2010. It also broke into fragments, though that may not be the right word. One of them alone was estimated to weigh 3.5 billion tonnes, or metric tons (3.86 billion short tons), according to E. Julie Halliday, a researcher at Memorial University in Canada.