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How the Great Green Wall is holding back the Sahara desert

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Re: How the Great Green Wall is holding back the Sahara desert

#31

Post by anonporridge »

micromacrofoot wrote: post #28
thinkingtoilet wrote: post #26

My question is are there downstream effects? The planting techniques are fascinating but the water that they are capturing surely was going some where, right? However little the stream may be, how do they do this without messing up people who are downstream?

hard to imagine a downstream effect that's worse than becoming part of the sahara

I think the concern is downstream effects negative to areas and people far away.

Like how the Sahara feeds the Amazon rainforest. https://www.nasa.gov/centers-and-facilities/goddard/nasa-sat...

i.e. greening your land might lead to browning mine.

Re: How the Great Green Wall is holding back the Sahara desert

#32

Post by groby_b »

blagie wrote: post #24
droningparrot wrote: post #22

Earlier quoted context omitted.

I think the big difference here is that the Qattara Sea would be a major engineering project involving specialized skills and machinery. The Great Green Wall is more open in that anyone can contribute to its construction. All you need is a shovel and some seeds.

Citation required and requested. I can plant a hundred trees, keep them up for a year, and find a hundred tree stumps in two. I genuinely would like to know where on the spectrum this is: - This is a fools' errand - This requires constant upkeep and detailed construction - This requires mild upkeep - This is self-sustaining, can be done with a shovel + seeds, and once started, is self-sustaining, with the forest turn…

This requires constant upkeep. The goal is to structure it so the local community is incentivized to invest that upkeep, but it's not just gonna happen all by itself. The goal is indeed a self-sustaining ecosystem, but one with human participation. If you want more detail, a good keyword is "Farmed Managed Natural Regeneration"

That keyword also makes it pretty clear it's more than a shovel and some seeds :)

And, fwiw, your request made me look at the thegreatgreenwall.org, and... good god. It is one of the lowest-information sites I've seen in a while. You could spend hours on there and learn nothing. https://thegreatgreenwall.org/science-and-the-ggw is as far as I can tell the only concrete part of this piece.

A much better starting point if you care about a bit more than feel-good vibing is https://www.unccd.int/our-work/ggwi

And that site makes it again abundantly clear that this is a very large scale project. The difference from the Qattara Sea project is that it actually managed to gin up multinational corporation, and that it takes a long term lens (as opposed to "IDK, let's flood this, rest's gonna work out" of the various seaflooding projects). And, most importantly, because it integrates the local communities in the project.

The last part matters because any such project is far from "fire and forget", and you need a strong local stake in any such project for it to succeed.

Re: How the Great Green Wall is holding back the Sahara desert

#33

Post by hooverd »

bcrosby95 wrote: post #6
debacle wrote: post #5

Earlier quoted context omitted.

I respect the right of Africa to try and reforest, but logically the most likely outcome is that the Amazon will start to die from the lack of the 30 million tons of dust and sand that fall on the Amazon each year from the Sahara. Should Africa's desert be preserved to feed the Amazon? That's a question humanity seems ill equipped to answer.

The Sahara desert is 3.5 million square miles. That will never be re-forested.

Found the Shai-Hulud.

Re: How the Great Green Wall is holding back the Sahara desert

#34

Post by bluGill »

blagie wrote: post #24
droningparrot wrote: post #22

Earlier quoted context omitted.

I think the big difference here is that the Qattara Sea would be a major engineering project involving specialized skills and machinery. The Great Green Wall is more open in that anyone can contribute to its construction. All you need is a shovel and some seeds.

Citation required and requested. I can plant a hundred trees, keep them up for a year, and find a hundred tree stumps in two. I genuinely would like to know where on the spectrum this is: - This is a fools' errand - This requires constant upkeep and detailed construction - This requires mild upkeep - This is self-sustaining, can be done with a shovel + seeds, and once started, is self-sustaining, with the forest turn…

It is designed by researchers who have been studying this for a while. At least for the near term the upkeep is worth it because people who previously no had prospects can now grow enough food to live on. You have to keep it up, but keeping it up means you can eat so the constant upkeep shouldn't be a problem so long as you are healthy. (culture or something is needed to deal with those who because of age or injury are not able to keep it up)

The real question is if in 50 years - as the current people use the fact that they have food and some extra invest in education for their kids, and so the kids move away to better city jobs. Those that remain likely love agriculture, but will be looking for ways use tractors to do the hard jobs. This doesn't seem to scale to large tractor operations. Those researchers thus need to look ahead to what follows this in 50 years.

Re: How the Great Green Wall is holding back the Sahara desert

#35

Post by groby_b »

anon291 wrote: post #4

It seems crazy to me that after we've had so many unintended consequences preventing earth's natural processes using technology, the same crowd is now celebrating using technology to prevent yet another of earth's natural processes. Regardless of your position on the Sahara desert, it's been growing since Roman times. Personally, I'm in favor of the use of technology to affect the planet, but it seems to me that the…

It's not about "who does the deed". It's about who accrues the benefits, and who has a stake.

Without a strong local stake, the only projects that work are resource extraction projects. These have a tendency to create dependencies, and strong political instability.

There's also the fact that many technocratic proposals from rich countries never progress past first order thinking: "Trees missing, add trees here". Again, a function of skin in the game - rich nations overwhelmingly operate on a form of capitalism that prioritizes short term wins, and they're not around for the cleanup after that. This is why you want a local stake - not due to theoretical arguments around capitalism or colonialism, but because you want to make sure the people who own the consequences are part of the process. Which usually leads to better outcomes.

Re: How the Great Green Wall is holding back the Sahara desert

#36

Post by glenstein »

battery_glasses wrote: post #15
anon291 wrote: post #4

It seems crazy to me that after we've had so many unintended consequences preventing earth's natural processes using technology, the same crowd is now celebrating using technology to prevent yet another of earth's natural processes. Regardless of your position on the Sahara desert, it's been growing since Roman times. Personally, I'm in favor of the use of technology to affect the planet, but it seems to me that the…

Why does that seem crazy to you? Some artificial interventions in the earth's natural processes are bad for humans (global warming, increased rate of desertification) and some interventions are good for humans (increasing land available for sustainable food production, killing malaria carrying mosquitos). There isn't some "human interventions good/human interventions bad" duality. Some are good some are bad. We shoul…

Exactly this. I think we have to wrestle with the fact that, as consumers of media, we sometimes become possessed by Trick Question Syndrome. So even if nothing about the facts indicates than an intervention is bad, treating it like at trick question feels like healthy skepticism.

Re: How the Great Green Wall is holding back the Sahara desert

#37

Post by skywhopper »

anon291 wrote: post #4

It seems crazy to me that after we've had so many unintended consequences preventing earth's natural processes using technology, the same crowd is now celebrating using technology to prevent yet another of earth's natural processes. Regardless of your position on the Sahara desert, it's been growing since Roman times. Personally, I'm in favor of the use of technology to affect the planet, but it seems to me that the…

Humans and technology have been around a lot longer than Rome. Do you think desertification is a completely natural process that has nothing to do with the humans who live in the area and what they do with the land?

Re: How the Great Green Wall is holding back the Sahara desert

#38

Post by begueradj »

Nearly all of the Algerian Saharan territory is surrounded by state made wall (dune) of 2-5 meters high.

Morocco also has similar and several walls: https://en.wikipedia.org/wiki/Moroccan_Western_Sahara_Wall

If there is money and resources to build and maintain such walls, there should be more will and good intentions to build green walls which are more useful.

Re: How the Great Green Wall is holding back the Sahara desert

#40

Post by skywhopper »

evandale wrote: post #29
VintageCool wrote: post #20

Earlier quoted context omitted.

Okay, sure, if you look at geologic timescales then eventually Africa will move and the region of northern Africa will cease to be desert. Within a human timescale, I think "never" is an acceptable term. Atmospheric circulation means that the latitude of the Sahara is blasted with cool dry air from the upper atmosphere. Humans planting trees might slow the spread of the desert, but will not vanquish it. To disrupt th…

Why are we working in human timescales? It's like saying the sun will never burn out because humans won't be around to see it happen. To me, that's a pretty bold and naive claim.

Because this project is about humans and the environment's impact on them, and what they can do to improve it. So naturally human timescales are the measure on which we judge it. What happens in 10 million years is not something we can even pretend to comprehend or influence in a meaningful way. But what happens in the next 100 is.
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