Frozen Planet II

Our journey begins out on the frozen Arctic Ocean, close to the North Pole. The sun is back after 6 months of darkness. We follow a pair of courting polar bears, which reveal a surprisingly tender side. Next stop is the giant Greenland ice cap where waterfalls plunge into the heart of the ice, and a colossal iceberg calves into the sea. Humpback whales join the largest gathering of seabirds on earth to feast in rich Alaskan waters. Further south, the tree-line marks the start of the Taiga forest, containing one third of all trees on earth. Here 25 of the world’s largest wolves take on formidable bison prey.

At the other end of our planet, the Antarctic begins in the Southern Ocean where surfing penguins struggle to escape a hungry sea-lion, and teams of orcas create giant waves to wash seals from ice floes – a filming first. Diving below the ice, we discover prehistoric giants – terrifying sea spiders and woodlice the size of dinner plates. Above ground, crystal caverns ring the summit of Erebus, the most southerly volcano on earth. From here we retrace the routes of early explorers, Scott and Amundsen, on their quest to be the first humans to reach the South Pole. Our journey ends at the formidable Antarctic ice-cap, which contains 75% of the world’s freshwater and is the largest concentration of ice on the planet.

Spring brings the appearance of the sun after an absence of five months; warmth and life return to these magical ice worlds - the greatest seasonal transformation on our planet is underway. Male Adelie penguins arrive in Antarctica to build their nests - it takes a good property to attract the best mates and the males will stop at nothing to better their rivals! But these early birds face the fiercest storms on the planet. In the Arctic, a polar bear mother is hunting with her cubs. Inland, the frozen rivers start to break up and billions of tons of ice are swept downstream in the greatest of polar spectacles. On land, a woolly bear caterpillar emerges from the snow having spent the winter frozen solid.

As the transformation of the Arctic reaches completion, it teams with life, migrating from the south. Amongst this influx, white Arctic wolves race to raise their adorable cubs before the cold returns. In Antarctica vast numbers of seabirds arrive on South Georgia joining the giant albatross and king penguins that have been there all winter. Elephant seals fight furious battles over females on a beach that contains the greatest mass of animals on the planet. Finally, the female Adelie penguins arrive, chased from the water by killer whales. Mating and chick rearing lie ahead of them.

It's high summer and the sun never sets. Vast hordes of summer visitors cram a lifetime of drama into one long, magical day; they must feed, fight and rear their young in this brief window of plenty. Summer is a tough time for the polar bear family as their ice world melts away and the cubs take their first swimming lesson. Some bears save energy by dozing on icy sun beds while others go egg-collecting in an arctic tern colony, braving bombardment by sharp beaks. There are even bigger battles on the tundra; a herd of musk oxen gallop to the rescue as a calf is caught in a life and death struggle with a pair of Arctic wolves. But summer also brings surprises as a huge colony of 400,000 king penguins cope with an unlikely problem - heat. The adults go surfing while the woolly-coated chicks take a cooling mud bath.

On the Island of South Georgia, a bull fur seal is prepared to fight to the death with a rival. Fur flies as the little pups struggle desperately to keep out of the way of the dueling giants. Further south, a minke whale is hunted amongst the ice floes by a family of killer whales. The dramatic chase lasts over 2 hours and has never been filmed before. The killers harass the minke whale, taking it in turns to wear it down. Eventually it succumbs to the relentless battering... Finally, comical Adelie penguins waddle back to their half a million strong colony. The fluffy chicks need constant feeding and protection as piratical skuas patrol the skies. When an unguarded chick is snatched, a dramatic aerobatic 'dogfight' ensues.

Autumn means dramatic battles and epic journeys. Time is running out - the Arctic Ocean is freezing over. Polar bears gather in large numbers on the Arctic coast as they wait for the return of the ice. Soon tempers fray and violent sparring contests break out. Meanwhile two thousand beluga whales head for one special estuary, to thrash their snow-white bodies against the gravel and exfoliate - it's a gigantic 'whale spa'. Inland, the tundra undergoes a dramatic transformation from green to fiery red. Here musk ox males slam head-first into each other with the force of a car crash at 30 mph, as they struggle to defend their harems.

Down in Antarctica, as the sea ice advances 2.5 miles a day, Adelie penguin chicks huddle together in crèches. When a parent returns from fishing, it leads its twins on a comical steeplechase - sadly there's only enough for one so the winner gets the meal...Two months later and the chicks are fully feathered apart from downy Mohican hairdos - they're ready to take their first swim... reluctantly - it seems penguins are not born with a love of water! And with good reason - a leopard seal explodes from the sea and pulls one from an ice floe - a hunting maneuver that has never been filmed before. As winter approaches, and everyone has left, the giant Emperor penguin arrives and makes an epic trek inland to breed. The mothers soon return to the sea leaving the fathers to hold the eggs and endure the coldest winter on earth.

There is no greater test for life than winter as temperatures plummet to 70 below and winds reach 200kph. Darkness and ice extend and only a few remarkable survivors gamble on remaining. We join a female polar bear trekking into the Arctic mountains to give birth as the first blizzards arrive. Out on the frozen ocean, the entire world's population of spectacled eider ducks brave the winter in a giant ice hole kept open by ferocious currents. Arctic forests transform into a wonderland of frost and snow - scene to a desperate and bloody battle between wolf and bison, but also where a remarkable alliance between raven and wolverine is made. Beneath the snow lies a magical world of winter survivors. Here tiny voles dodge the clutches of the great grey owl, but cannot escape the ultimate under-snow predator - the least weasel. Midwinter and a male polar bear wanders alone across the dark, empty icescape. Below the snow, polar bear cubs begin life in an icy den while fantastical auroras light the night skies above.

In Antarctica, we join male emperor penguins in their darkest hour, battling to protect precious eggs from fierce polar storms. Weddell seals escape to a hidden world of jewel-colored corals and alien-looking creatures, but frozen devastation follows as sinister ice stalactites reach down with deadly effect. The sun finally returns, and with it comes the female emperor penguins, sleek and fat, ready to deliver the first meal to their precious chick. Having survived winter, this ultimate ice family now have a head start in raising baby. The adelies flood back and as the ice edge bustles with life, male emperor penguins can finally return to the sea.

We reveal the extraordinary riches and wonders that have kept people coming to the Polar Regions for thousands of years. Most Arctic people live in Siberia, either in cities like Norilsk - the coldest city on earth, or out on the tundra where tribes like the Dolgan survive by herding reindeer, using them to drag their homes behind them. On the coast, traditional people still hunt walrus from open boats - it's dangerous work but one big walrus will feed a family for weeks. Today settlers are drawn to the Arctic by its abundant minerals: the Danish Armed Forces maintain their claim to Greenland's mineral wealth with an epic dog sled patrol, covering 2000 miles through the winter. Above, the spectacular Northern lights can disrupt power supplies so scientists monitor it constantly, firing rockets into it to release a cloud of glowing smoke, 100 kilometers high. In contrast, Antarctica is so remote and cold that it was only a century ago that the first people explored the continent. Captain Scott's hut still stands as a memorial to these men.

Today science is the only significant human activity allowed in Antarctica: robot submarines are sent deep beneath the ice in search of new life-forms, which may also be found in a labyrinth of ice caves high up on an active volcano. Above, colossal balloons are launched into the purest air on earth to detect cosmic rays.

The Poles are warming at up to five times faster than the rest of the Earth. If this continues, it won’t just affect the people and wildlife that lives there – it will affect the planet as a whole. From pioneering camera techniques, to satellite imagery and scientific experimentation and prediction, Meltdown looks to the future of not just the landscape of the poles, but also to those that live within them. The polar bear is reliant on the sea ice, and without it, their future is seriously threatened, with some experts predicting that the species will not last to the end of this century. However, no one has to adapt faster to the changing nature of the Arctic, than the indigenous people that live there. The hunters face daily dangers attempting to hunt prey on ice that is too thin, buildings can topple due to melting permafrost and coastal villages could be washed away as the absence of sea ice exposes them to the full fury of the winter storms.

Overwhelming evidence collected during the filming of Frozen Planet shows the speed with which climatic changes are occurring. The movement of the glaciers in Greenland is a prime example of this. The Greenland glaciers are the world's second largest ice sheet. Using extraordinary time-lapse photography, Meltdown is able to show how they are moving towards the sea - at an astonishing rate of 120 feet a day, almost fast enough to view with the naked eye. With access to the Poles' most extraordinary locations and featuring interviews with leading scientists, Meltdown looks for definitive answers to some of the most pressing questions mankind has ever faced.