PLANET EARTH Ice Worlds

Two weeks later they're ready. Out on the sea ice the female can hunt for seals but it will take all her mothering skills to keep her cubs safe in this dangerous world of ice. The annual melt has begun. This is a challenging time for the bear family. One out of every two cubs do not survive their first year out on the ice.



As the sun's influence increases, the sea ice seems to take on a life of it's own. Glacial（冰川） melt waters pour from the land mingling（混合） with the sea and speeding up the thaw. The seascape is in constant flux, as broken ice is moved on by winds and currents. The ice is becoming too weak to support a male polar bear. He attempts to spread his weight but the ice that has supported him all winter is rapidly disintegrating.



Each year as the climate warms the Arctic holds less ice. This is a disaster for polar bears. Without its solid platform, they can't hunt the seals they need in order to survive. This may be a glimpse of the unstable future faced by this magnificent creature. As the ice disappears seabirds return to the high Arctic. Little auks（海雀） arrive in their millions. In some ways these birds are the penguins of the north. The seek bare rock on which to lay their eggs and they look rather like penguins too.