Whale rider:

Julia Petrik, had to cut through ice one foot thick to get in to the -2C (28F) water off the north-west coast of the country.

Miss Petrik, 38, one of the world's top free divers, swims underwater with no air tanks and can hold her breath for up to two minutes.

After entering the water she grabbed hold of a passing Beluga Whale for a lift - a moment captured by British photographer Dan Burton.

Brief encounter:

Temperatures above the ice were as low as -15C (5F) and during the free-dive Miss Petrik swam to depths of 82ft, wearing only ultra-tight wetsuits, face masks and flippers.

Miss Petrik managed to grab the whale for a free ride at around 26ft and floated for several seconds before letting go.

Beluga Whales only live in Arctic and sub-Arctic waters and are protected from the sub-zero temperatures by a thick layer of blubber.

"What was amazing was how dark it was underneath the ice. When you looked up there was this green glow - it was like another world, breathtaking."