In this final episode we complete our journey, travelling back from the March equinox to the end of June. Kate Humble is in the Arctic at a place where spring arrives with a bang, whilst Helen Czerski chases a tornado to show how the earth's angle of tilt creates the most extreme weather on earth.
Patrick follows the grizzly bears that are taking a risk with the weather by leaving their winter dens early. Hungry wolves are struggling to bring down their elk prey in the unusually shallow snow. And for great grey owls, it is the iciness of the snow that is hampering their hunts. Yellowstone's winter is always one of the most brutal on the planet. But 2016 saw weather records broken, and the wildlife was forced to adapt to survive. Kate Humble gets to grips with the science behind this remarkable season, from understanding the importance of the snowpack's structure as the melt begins to uncovering why Yellowstone's unique geology poses problems for some grazer's teeth.
59m • 2016 • Yellowstone: Wildest Winter to Blazing Summer
The migration of the painted lady has long fascinated scientists, artists and nature lovers alike. The longest butterfly migration on earth, it sees millions of these delicate creatures travel from the desert fringes of north Africa, across thousands of miles of land and sea, before settling in the UK. However, the migration has never truly been understood, the mysteries of the painted lady never unravelled - until now.
89m • 2016
The adventurer reaches Sri Lanka, whose strategic location and tropical spices made it a target for invaders and colonisers for centuries. In the north he visits the scenes of vicious battles between the Tamil minority and the Sri Lankan army, traumatic events from which the population is still recovering. On his way to Bangladesh, he hitches a ride on a trawler, highlighting one of the Indian Ocean's fastest-growing industries - providing prawns for the West. But as he reveals, it comes at a price for the environment.
59m • Indian Ocean