Episode 3 of the Arctic Meltdown series from The Nature of Things tracks two different Arctics — one that is the storybook land of ice, snow and polar bears and the other that is covered with petroleum plants and pipelines carrying fossil fuels. Bylot Island is a national park and for 20 years a team of Canadian scientists have come every summer to measure the impact of climate change on snowy owls, lemmings, snow geese and Arctic foxes. Here they have discovered that even tiny, hardy plants are being affected, causing a cascade of changes through the ecosystem.