The last leaf of the world fell in 2096,

No more trees, all dead, or burned by the wildfires. The last leaf came from a young sapling that had been planted into the soil two years before.

The forests had gone. Most of the grass had gone. Algae in the sea was dying. The only thing creating oxygen were the chlorophyll pumps. Miles high, miles wide, the stirrers ran 24 hours, day and night, month after month, year after year.

So now what…? Quantum jiggery pokery…. DNA, cloning. If the Earth could cool the planet could be reforested, but that would take decades….