An AP story carried on NPR’s site reports that an enormous piece of the Petermann Glacier in Greenland, a chunk of ice twice the size of Manhattan, has fallen into the sea surrounding that far northern continent. While glaciologists can’t yet say for sure this was caused by climate change, it is of a piece with recent melting that’s been occurring all around the massive landmass. A series of maps and satellite photos from NASA shows these changes, which actually occurred in August 2010, though examination of the photos has only recently yielded discovery of the event. Scientists will continue to study this event, as they try to determine if this was a glacier calving off a large part of itself, or whether the 46-square mile chunk of ice caved in to the ocean as a result of global warming.