Africa Aims To Combat The Effects Of Climate Change By Greening The Desert

great-green-wall-full-300x239In Africa, climate change is exacerbating the desertification of the continent. The Sahara Desert, which covers the majority of northern Africa, is spreading southward at a rate of 30 miles per year.

This spread of desert sands into the semi-arid region of the Sahel is causing problems for the people who live there, as The Ecologist reported last year:

Senegal’s capitol city Dakar sticks out into the Atlantic Ocean on a peninsula. It’s at least a thousand miles to the Sahara desert yet the air today is so thick with sand that the tops of buildings disappear in a sandy haze. It’s the worst sand storm in a year and people here are worried that climate change will cause these events to be more common. Seasons are shifting across the region. In Senegal the rainy season used to start in July or August but now it doesn’t start until September. Decreased rain – along with over grazing of land – is causing an increase in deserts across the Sahel.

Desertification affects about 40 percent of the continent, and according to the U.N., two-thirds of the continent’s arable land could be lost by 2025 if the trend continues unabated. Africa has recognized these threats and has turned to projects that re-vegetate the land in hopes of holding off the spread of the desert.

One initiative, the Great Green Wall, aims to battle desertification by planting a wall of trees and vegetation from coast to coast across the continent, below the southern edge of the Sahara. Once completed, the wall will be 4,300 miles long and 9 miles wide and will cut through 11 African countries in the Sahel region of the continent. The plan was approved by the African Union in 2007, and in July 2008, the 11 countries in the wall’s path began planting their trees.

The trees and vegetation are planted to prevent erosion and slow wind speeds, but they also provide fruit and vegetables for Africans in a region that is in the midst of a food crisis — according to the United Nation’s Food Program, as many as 11 million people in the Sahel don’t have enough to eat. In Senegal, which is farthest along in the planting of the wall, 2 million trees are planted each year during the rainy season. Already Senegal has been able to reap the benefits of the fruit and vegetables grown along the wall, but it will take some time to assess its effectiveness at combating desertification– it will be another 10 to 15 years before the wall becomes a forest.

A similar project aims to create green jobs through re-vegetation efforts in Africa. The Sahara Forest Project plans to develop large-scale desert oases in northern Africa using concentrated solar power, outdoor vegetation, saltwater greenhouses and algae cultivation. Using solar-powered desalinization processes, the greenhouses would grow produce such as tomatoes and melons, and algae cultivation centers and would produce “bio-fuel ready” algae oils. The project is supported by the U.N. and has established a pilot facility in Qatar.

As well as facing the threats of desertification, many in Africa also struggle to power their homes — Africa’s electricity prices are among the highest in the world. Africa has been historically slow to invest in renewable energy, parts of the continent are slowly emerging as markets for solar power, helping to mitigate climate change as well as adapt to its effects. This February, South Africa began construction on two 50 MW solar photovoltaic plants in the Northern Cape province. Algeria plans to install 1.22 GW of photovoltaic solar power by 2022, and in Ghana, a solar installation set to begin this year will provide power to more than 100,000 homes.

17 Responses to Africa Aims To Combat The Effects Of Climate Change By Greening The Desert

  1. Pennsylvania Bob says:

    Perhaps a typo on the length of the wall? Maybe 4,300 miles?

  2. fj says:

    Scale of this thing is amazing . . . terribly exciting!

  3. fj says:

    . . . really puts the piddling lack of vision we seem to have in this country to shame.

  4. The way that deserts are spreading makes me concerned for our position here in the North of New Zealand. We have a lot of rain but our latitude is at 32S and most deserts are currently at about 35 north or south. Our environment agency is forecasting that our area is going to get warmer and receive less rain and although changing from a green and pleasant land to a desert seems improbable at the moment it is a concern.

  5. Rabid Doomsayer says:

    So many reasons this may not work. But if it does work, what a payoff. Even if only partially successful still well worth the effort.

    On this day of bad news, some good news is welcome.

  6. Gillian says:

    This statement (Africa has been historically slow to invest in renewable energy) is only true if you ignore hydro power.

    Forty-six countries, worldwide, get more than 60% of their electricity from renewables. Seventeen are African countries that rely on hydro electricity.

    On average, it’s possible that African countries get a higher proportion of their meagre electricity from renewables than OECD countries.

    In desperately poor African countries investment in large-scale electricity projects depends heavily on support from institutions like the IMF and World Bank. When THEY support renewables we’ll see more African countries investing in large-scale wind and solar. In the meantime, the shift to distributed power generation may well be overtaking large, centralised electricity systems.

  7. Joan Savage says:

    Australia already has a large scale example of the difference it might make. The rabbit fence in Australia has separated forest from agricultural land. One of the most impressive results of that barrier is that clouds form over the green forest, not the brown agricultural land.

    An aerial photo of the contrast by Udaysankar S. Nair has been reproduced many places. The one with the most memorable title is Living On Earth’s “Fencing the Weather.”

  8. Sean says:

    This is an interesting development. However the claim of over-grazing being to blame is disputed by Allan Savory, who has been working on the problem of desertification, in Africa, for a long time.

    See this video:

    He shows that using livestock and a well planned grazing pattern can reverse desertification.

  9. Daniel Coffey says:

    The improbable will become the ordinary as the energy content of the oceans and atmosphere continue to increase. There will be more moisture in the air and less chance for it to precipitate out as rain because there are fewer “cool” spots.

  10. Adam Sacks says:

    Savory and others have been working in grassland restoration for over forty years one four continents – and the results are remarkable. Grazing animals are essential to the process – the wild ruminant population is a fraction of what it once was, but livestock properly grazed fill the same niche.

    I’ve been trying for years to get Joe to move this discussion forward on CP, but he refuses for reasons that escape me.

    I would think it’s something we should all be talking about, since emissions reductions to date have been a tragic failure. Of course we should reduce emissions, but it’s even more urgent to remove carbon from the atmosphere and back into the soils.

    How about it Joe?

  11. Mulga Mumblebrain says:

    Graziers here in Australia have had great success with intensive stocking of small areas for short periods, then leaving the area alone for a long time in order to recover.

  12. Joan Savage says:

    FAO published a report on the role of grassland in climate change. Figure 5 (page 29) shows that at maximum effort, grassland could make a significant contribution, but would not be able to keep up with less than half of the current CO2 emissions.

    We still have reduce emissions.

    The Drovers Cattle Network has posted an enthusiastic article about Savory, but hints at a significant caveat for American cattlemen, who have boosted productivity per acre by ‘finishing’ in feed lots.

    “As long as time of exposure of the pasture or range unit to grazing is a key component of the management, any class of domestic livestock can be used as an effective tool for ecosystem enhancement,” Gerrish says. “Ted Turner learned pretty quickly that fenced-in bison without management were no better for the environment than were beef cattle.”

    The kind of sustainable grazing promoted by Savory takes more acreage per animal. Not a bad idea.


    We still have reduce emissions.

  13. Adam Sacks says:

    Thanks for these observations, Joan. One of the problems with the conventional approach to soils is the assumption that the carbon-storing capacity of soils is limited to their geological capacity (soils created by weathering of rock over thousands and millions of years). We are learning that biological creation of soils on grasslands has a far greater and faster carbon storage capacity. One inch of new soil a year is feasible in some circumstances (a ton or more of carbon captured per acre). From a soil science perspective, this is a paradigm shift.

    It is altogether possible that the world’s grasslands, mostly degraded at this point, could sequester not only all legacy carbon, but enough to return atmospheric burdens to pre-industrial levels in under four decades.

    Of course we should reduce emissions to zero. But we haven’t been able to do that, it’s questionable how soon we’ll be able to do it, and even if we did how that would affect outcomes with all the feedbacks in play. We have to pull carbon out of the atmosphere.

    This is a discussion we should have on CP’s front page. There is literally nothing else on the horizon at the scale we need. And grassland eco-restoration has so many benefits in addition to addressing climate we should move ahead with all possible haste.

    Joe, you there?

  14. Daniel LaLiberte says:

    Why not eliminate emissions AND restore grasslands and forests? We need to do all that, and more. Why argue false dichotomies? It will take time to do any of it, and we need to do all of it as soon as possible, as fast as feasible.

  15. Mulga Mumblebrain says:

    Absolutely. We have centuries of ecological repair in store for us, and we need a steady-state economy, global equity and equality and a greatly reduced human population, too.

  16. Joan Savage says:


    Meanwhile the proponents of restoring grasslands should be prepared to discuss methane emissions from ruminant herds, already a significant component of human-added greenhouse gases.

  17. Joan Savage says:

    I couldn’t agree more.

    Were it not for exploitation of fossil fuels, the human population might have maxed out at 1.09 billion or less.

    The optimistic view of retaining an enormous 7 billion-plus population that shifts to other forms of energy doesn’t really work, as Peak Fresh Water has come and gone, and Peak Fertilizer/ Soil Fertility is somewhere around. (I know the grassland people want to pound on that point, but it’s only part of the picture.) Those catastrophes would be enough, even without the exacerbation of increased climate instability, which puts a sort of torque on any other factor.

    Would that we could gracefully reduce our current numbers back down, without doing further harm.