This blue ice can be seen however under certain circumstances. It can be seen in winter after long periods of rain when the surface layer of the glacier has been washed away and the weak arctic winter sun can not redamage it right away. It can also be seen in ice-caves like this one (unsafe in summer) and on floating icebergs that reveal their bottom side when they have recently rolled over.
This ice cave is on the edge of the glacier where it enters into a lagoon. It is only possible to access it when the lagoon is frozen. Ice caves are in general unstable things and can collapse at any time. They are however much more stable in winter when the cold temperatures harden the ice. Even so we could hear constant cracking sounds inside the cave. It was not because it was going to collapse but because the cave was moving along with the glacier itself. Each time the glacier moved a millimeter loud sounds could be heard.”