"The polar bear's presence is entirely transitory, with photography dependent on accurate timing, the right weather and exceptional luck," said Steve. "Imagine a world without polar bears. It seems unthinkable, yet as climate change gathers pace, the Arctic ice floes upon which the polar bear depends are beginning to break up. In the years ahead, this could be catastrophic for this truly charismatic bear which, when it stands up, is taller than the largest elephant. A polar bear plunges into the water in Norway Picture: Pierre Vernay / Barcroft Media

Credit : Pierre Vernay / Barcroft Media