Frozen in iceberg is surrounded by spring melt water at Lancaster Sound Nunavut Canada Arctic.

- Image ID: B58C58
louise murray / Alamy Stock Photo
Image ID: B58C58
During the Arctic spring the surface of the frozen arctic ocean begins to crack under stress as the ice thins from above and the actioon of currents and warmer sea water below These cracks or leads act as drains for meltwater runoff from the surface