John, I agree with your post about the population crisis but our deserts are in fact getting greener due to CO2 fertilization.

CSIRO research shows the CO2 fertilization effect occurs where elevated CO2 enables a leaf during photosynthesis to extract more carbon from the air or lose less water to the air, or both. 

Essentially, plants in the desert are using far less of the limited water the area receives and are slowly encroaching in deserts like the Sahara and in Australia where the research was conducted.

We're only getting increased desertification in areas affected by dramatic human deforestation which has little if anything to do with climate but caused by the forestry industry or locals depleting limited trees for fuel or shelter.