Episode 1

Greta travels through North America on her way to a UN climate conference in Chile. To understand the impact of climate change, she stops at three key locations that reveal how the planet is changing.

In the Canadian Rockies, she learns how a small change in temperature has allowed an insect infestation to kill nearly half the trees in one of its most famous national parks. She visits a glacier that is melting faster than models predict, and discovers the cause is partly due to soot from forest fires falling on it.

In California, she sees at first hand the destruction these fires create when she visits Paradise, a town at the centre of a deadly fire in 2018.

When the UN climate conference is suddenly moved to Madrid, Greta finds herself on the wrong side of the Atlantic Ocean and decides to sail back, braving life-threatening storms, to make her speech calling for immediate action on climate change.