Oceans are the largest ecosystem on earth, covering two thirds of our world’s surface and providing half the oxygen in our atmosphere. They are home to as much as 80 per cent of all life on earth, and nearly three billion people rely on them for their primary source of food. But our planet’s oceans would be little more than stagnant wastelands, and life on planet earth would cease to exist, were it not for one simple factor: a global network of powerful ocean currents. Every drop of seawater on earth rides these currents, taking 1,000 years to complete a single circuit. Without the constant mixing of currents, tides and waves, our oceans would stop supporting life - and a healthy ocean is vital to a healthy planet.
The Namib Desert is one of the oldest deserts and also one of the most diverse. With 50ºC (120ºF) temperatures and half a millimetre of rainfall annually, we see how this is possible. Half the size of Oklahoma, from its Skeleton Coast through the sea of sand to the haze of distant mountains this apparently forbidding desert hides secret water sources.
At the very end of East Africa's Great Rift Valley, there's a 'land that time forgot'--the rolling grasslands of the Luangwa Valley. Seemingly untouched plains teem with Africa's most iconic animals. Some are unique to this place, others are critically endangered elsewhere. Here, prey exist in remarkable balance, each taking advantage of the secret at the heart of this Eden, the mighty Luangwa River and its dramatic annual transformation from dusty inferno to emerald paradise.
600 miles off the coast of South America in the Pacific Ocean there are 120 tropical islands that erupted from the deep ocean floor more than 10 million years ago. Journey from the lava ramparts to its fiery heart, we'll discover how the Galapagos archipelago became one of the most important areas of biodiversity in the world. Those swept here by storms and currents survived million to one odds to find untouched islands free from competition. These hardy pioneers evolved in remarkable ways in what's known as Nature's Greatest Experiment. Home to bizarre specialists and unexpected giants, the most precious collection of island creatures on Earth.
At the far tip of South America, lies a magical realm that seems frozen in time. Known as 'the end of the world', this is Patagonia. Vast glaciers shaped it into an Eden like no other. Adaptable and resilient creatures evolved unique survival strategies to flourish across its remarkable habitats. From precipitous mountain citadels and icy desert plateaus windswept steppe uplands through remote, primal forests to a mosaic of glacial valleys. To thrive here is to be as extreme as the land itself.
In Southeast Alaska, there's an ice-bound Eden that harbors possibly the richest temperate rainforests of all. Where the coastal mountains meet the Pacific, lays the Alexander Archipelago, a remote island chain running for almost 300 miles along the Alaskan Panhandle. This frozen frontier is one of the last great wildernesses of North America. And a stronghold for the country's highest diversity of megafauna, feasting on the abundance of fleeting summers to make it through relentless winters.
But our planet’s oceans would be little more than stagnant wastelands, and life on planet earth would cease to exist, were it not for one simple factor: a global network of powerful ocean currents. Every drop of seawater on earth rides these currents, taking 1,000 years to complete a single circuit. Without the constant mixing of currents, tides and waves, our oceans would stop supporting life - and a healthy ocean is vital to a healthy planet.