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Finalist in the Ecosystem category!

A NOVA Production by Windfall Films Ltd, (part of the Argonon Group) for GBH in association with France Télévisions, ABC Television, and ZDFinfo.



In 2015, ecologist Tom Crowther used state-of-the-art techniques to tackle a simple question: How many trees are there on Earth? His answer, 3 trillion, was vastly more than previous estimates – and he identified a billion hectares of land where a trillion new trees could be grown, unleashing a global tree-planting frenzy. But a few years later, scientists questioned his methods, saying his estimate of how much carbon forests could absorb was 5 times too high, and he became a symbol of greenwashing by corporations and governments trying to “offset” their emissions rather than reducing them.


Now, together with scientists around the world, Crowther is determined to find out what role Earth’s forests can play in the fight against climate change. Secrets of the Forest follows them around the globe as they race to understand just how much carbon forests can remove from the atmosphere and how microorganisms, plants, animals, and humans combine to sustain healthy environments. Our cameras travel to spectacular forest landscapes in Costa Rica, Canada, Brazil, Madagascar, and beyond as they gather data on how forests work and try to figure out how these remarkable ecosystems can help tackle the twin threats of climate change and species extinction.

  • Runtime
    53 minutes
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