Africa's great green wall suffers from a major mismatch between ambition and effort. But that's not to say it should be ditched altogether.
Poverty and conflict mean the nation is struggling to deal with rising temperatures.
The world's biggest desert used to be green, lush and full of hippos. A new theory suggests humans could have tipped the environment over the edge.
As grassland turns to desert, dust is blown into the atmosphere and across oceans.
On the African continent, more fire for crops leads to less rainfall.