The man who predicted deforestation and climate change 200 years ago

The man who predicted deforestation and harmful human induced climate change 200 years ago. When Alexander von Humboldt explored the South American rain forests he realised that nature was a 'web of life' and witnessed how human activities were catastrophically damaging the landscape. Historian Andrea Wulf argues that climbing Chimborazo, then believed to be the highest peak in the world, was Humboldt's equivalent to modern day satellite pictures showing the devastation of deforestation. Looking down he recognised the significance of what he saw, so why did it take so long for science to take such concerns seriously? Philip Ball discusses this question with Kathy Willis, Director of Science at Kew Gardens.