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The American president struggles to match his green aspirations with political reality.
Three kilometres underground, the Dinaric Arc has been called Europe's Amazon forest.
For the second part of his series on slums, Paul Mason asks if they are here forever.
The world's slums are booming - so what can they teach us about enterprise and community?
Filthy and embarrassing, the Ganges needs help - we explore how the Thames can save it
We visit western Hungary and find out how the area hit by toxic sludge is recovering
Claims that China leads the green revolution at home, but lags behind abroad
Turbines are popping up around the world, but in the Welsh valleys, locals have had enough
Australia ignites the carbon tax debate, and China comes clean on its secret oil spill
Development in a new country, South Sudan. Plus asking the poor for advice