Great Green Walls

First there was the Great Green Wall of China, begun in the late 1970's.



Then several decades later, Africa began its own Green Wall.



And the idea has been repeated in other places as well: plant many trees along the edge of a desert, in order to stop the desert from spreading. In China and in Africa, there are dramatic stories of regions which had been almost uninhabitable, being restored to fertile, sometimes even lush condition. Stories of farmers moving back to regions which they had abandoned.

In addition to curbing the growth of the desert -- the Gobi Desert in the case of China, the Sahara in Africa -- the atmosphere is cleaned, by taking carbon from the air and storing it in trees. Reducing the amount of carbon which is put into the atmosphere, by burning things like oil, coal and gas, is just one half of the solution to global warming. The other half is increasing plant life.

Planting trees in areas where there had been none previously is referred to as afforestation, as opposed to reforestation, replacing forests which had been removed. The Green Walls are just the two largest examples of afforestation currently underway in the world; smaller projects have been started all over the world.

As far as just exactly how large the Green Walls in China and Africa are -- I've found it very hard to find any precise statistics. For example, I can't tell you for certain whether the number of trees planted so far in China's Great Green Wall is in the millions, or the billions. And I would love to be able to tell you in great detail just what sort of changes of temperature, precipitation and so forth have occurred in the areas covered by the Green Walls, but I haven't been able to find that data either.

Also, there is some controversy over just how helpful afforestation is for the climate overall, and about just exactly what are the best methods for restoring arid regions. So, as always: education is crucial. In this case, education about all the positive and negative effects of afforestation, and about all the other methods to combat the spread of deserts. All I can tell you for sure is that I surely hope that afforestation is at least close to as effective as its most enthusiastic advocates claim.