Nasa captures images of mysterious crack in one of Greenland's biggest glaciers

A mysterious and worrying crack in Greenland's Petermann Glacier – one of the largest on the ice covered island – that connects the Greenland ice sheet to the Arctic Ocean has been photographed by Nasa. According to reports, the new rift is relatively close to another wider and longer crack, which has been slowly making its way toward the centre of the glacier from its eastern side wall, raising concerns about the possibility that part of the ice shelf is splintering off into the ocean.

The images show that the new crack has appeared at the centre of the glacier's floating ice sheet, which is considered to be an unusual location, raising questions about how its formed. The images of the new rift were taken by Nasa's airborne mission – Operation IceBridge on Friday (14 April) after Stef Lhermitte, a professor at Delft University of Technology in the Netherlands, first discovered the unusually located crack in satellite images and provided coordinates to Nasa scientists.

The Washington Post reports that if the two rifts intersect, it could result in a single massive break that could eventually shatter it. However, this may be prevented, thanks to a medial flow line, which Operation IceBridge scientists said, may have a "stagnating effect" on the new crack, meaning, it advancement toward the earlier rift may be slowed or halted.

Lhermitte noted that satellite time series images revealed that the new crack has been growing since July 2016. Although scientists are not clear on what may have caused the new rift to form, Lhermitte suggested that whether "ocean forcing" – a phenomenon that occurs when warm oceam waters melt the ice from beneath – may be responsible for the formation of the new crack.

Nasa's IceBridge operation that collects and documents data from Greenland and Antarctica by flying instrumented aircraft over the ice at both poles, is aimed at understanding how the environment is changing at the poles. Scientists will now pour over IceBridge's latest data to understand what caused the latest crack in the Petermann Glacier and whether it may accelerate further changes to the glacier.