A large ice island has broken off the Petermann Glacier in northern Greenland.

NASA satellite image (MODIS).

This iceberg is about twice the size of Manhattan but approximately half the size of the previous recent break-off in 2010 (blog post here).  Unlike the 2010 event the current ice has broke off further up glacier and marks a retreat of the calving front of the glacier.  The crack and rift that led to this break off has been known and observed for some time and so this event was expected in this regards.  However, the question is still being asked as to how unusual these large calving events are and whether they were caused by climate change.  Certainly we can say that these changes have not been seen for at least a 150 years (see previous post and this discussion article).  However, we can’t say for certain that these two massive calving event are a direct result of climate change.  An interesting discussion on these questions is provided in this BBC article.

The Guardian has a little interactive page where you can watch the iceberg break off in context (click here).

Glaciologist Tim Creyts provides an insightful radio interview here.