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Many more trees could be planted without encroaching on crop land or urban areas

theguardian.com

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Re: Many more trees could be planted without encroaching on crop land or urban areas

#41

Post by lrem »

tobltobs wrote: post #34
lrem wrote: post #30

The key phrase of the article: “Without freeing up the billions of hectares we use to produce meat and milk, this ambition is not realisable,” This is the polar opposite of what is happening at the moment. In particular: https://edition.cnn.com/2019/07/02/americas/amazon-brazil-bo...

Why do you cut of the second part of this sentence? “Restoring trees at [low] density is not mutually exclusive with grazing. In fact many studies suggest sheep and cattle do better if there are a few trees in the field.”

Because it is not that relevant, for two reasons:

1. Most land used to produce meat and milk is actually not by grazing.

2. I was tunnel-visioned on the part I added. The article calls for reforesting 1.7G hectares, at average 50% density, for a total of 850M. Amazon is being deforested at about 500k-1M hectares per year[1] and the political climate suggests making it worse rather than better. According to a quick googling, over half of Amazons trees are over 300 years old and the deforestation is done with fire, effectively instantly undoing 300 years of sequestration. So, within 3-6 years of business as usual just the Amazon deforestation balances out a year of this theoretically possible global effort.

Please prove me wrong, I don't want this to be true :(

Edit: TFA calls for 1.7G (not T) hectares with 1.2T trees.

[1]:https://news.mongabay.com/2019/05/new-report-examines-driver...

Re: Many more trees could be planted without encroaching on crop land or urban areas

#42

Post by Retric »

jwr wrote: post #12
skosch wrote: post #10

Interesting – we need more of such studies. Check out Drawdown [0] for other interventions with quantified costs/benefits. Economists widely agree that carbon pricing is the most effective way to fix climate change [1], and fee-and-dividend implementations are the most viable politically (there's a bill before Congress now [2]). [0] https://www.drawdown.org/ [1] https://www.nytimes.com/2018/10/08/business/economic-sc…

> Economists widely agree that carbon pricing is the most effective way to fix climate change That is true, and does not conflict with the findings of the article. I think the difference here is that we can start planting trees right now. Carbon taxation is something people still pretend doesn't have to be done. It's also worth noting, that given the accelerating pace of the climate crisis, the time to start planting…

Most people are overestimating the value in planting trees.

Trees readily plant themselves in areas they are well adapted to. Areas that don’t quickly turn into forests are generally poorly suited to growing trees.

Further, not all trees are equivalent with marginal areas generally resulting in small and often very slowly growing trees.

Re: Many more trees could be planted without encroaching on crop land or urban areas

#43

Post by lozenge »

notatoad wrote: post #29
mariushn wrote: post #26

Earlier quoted context omitted.

I always thought that carbon/green certificates taxes go towards environment/renewable energy, but I'm probably too naive... How to minimize the Tragedy of the commons effect? Where countries don't want to impact their economic growth because other countries won't impose such taxes, therefore some production will move there.

>How to minimize the Tragedy of the commons effect? Where countries don't want to impact their economic growth because other countries won't impose such taxes, therefore some production will move there. This was the point of the Paris Agreement.

The Paris agreement did nothing about this. It is completely non binding. The actual emissions reduction plans (INDCs) were drafted by each country and not negotiated.

Re: Many more trees could be planted without encroaching on crop land or urban areas

#44

Post by pochamago »

graeme wrote: post #33
notatoad wrote: post #21

Earlier quoted context omitted.

I believe carbon pricing has two aspects - one is to charge carbon emitters, the other aspect is to use that money to do something that reduces existing CO2 levels. Just charging emitters does not completely solve the problem, so research into the best ways to spend the funds generated by carbon pricing is critical.

It depends. You could, for example, make high carbon taxes while reducing income taxes or dividending the money back to people. This would let you have more of a carbon blocking effect while keeping government revenues steady. If you use the money for a specific purpose, then you either need low carbon taxes to avoid radically altering the government’s role in the economy, or you are making a large bet that the gover…

I imagine you include deductions, like most tax systems, with actions like planting trees being counted against your emissions. For many businesses that would be a more effective way to spend, and likely more efficient than the government middle man doing the work

Re: Many more trees could be planted without encroaching on crop land or urban areas

#45

Post by pdonis »

skosch wrote: post #10

Interesting – we need more of such studies. Check out Drawdown [0] for other interventions with quantified costs/benefits. Economists widely agree that carbon pricing is the most effective way to fix climate change [1], and fee-and-dividend implementations are the most viable politically (there's a bill before Congress now [2]). [0] https://www.drawdown.org/ [1] https://www.nytimes.com/2018/10/08/business/economic-sc…

> Economists widely agree that carbon pricing is the most effective way to fix climate change

Those economists are basing that claim on two highly questionable premises:

(1) That we know with high confidence that reducing CO2 levels will "fix" climate change. We don't know that. Climate models based on that assumption do not make accurate predictions.

(2) That we know with high confidence the economic consequences of particular interventions such as carbon pricing. We don't know that either. Economists' predictive ability is even worse than that of the climate models.

Re: Many more trees could be planted without encroaching on crop land or urban areas

#46

Post by jillesvangurp »

It can actually be better than this still. Cattle can be part of a solution to helping restore arid land where the soil has been destroyed by intensive farming and erosion. Healthy soil stores enormous amounts of biomass (aka carbon). Intensive farming has destroyed enormous amounts of land world-wide and turned it into desert, releasing lots of CO2 into the atmosphere.

This is a reversible process and catlle is part of the solution: https://www.theguardian.com/environment/2011/jul/22/cows-cli...

So, using large herds of cattle to refertilize bits of land that are currently not usable for agriculture would capture enormous amounts of carbon in the soil, restore the water retention capability of arid land, put a stop to large scale erosion of remaining soil, and restore it to productive land that may be used for growing food. Alternatively, once restored, you can sit back and watch the land reforest itself or use planned grazing to keep it as grassland. There's no actual need to manually plant trees; though it does probably speed up the process.

Finally, using cattle to fix land produces lots of nice organic/free range meat in a sustainable way as a side effects. And yes, cow farts have a green house effect but it is offset by the captured CO2 in the restored soil. Healthy soil has lots of biomass.

Re: Many more trees could be planted without encroaching on crop land or urban areas

#47

Post by Ericson2314 »

tobltobs wrote: post #34
lrem wrote: post #30

The key phrase of the article: “Without freeing up the billions of hectares we use to produce meat and milk, this ambition is not realisable,” This is the polar opposite of what is happening at the moment. In particular: https://edition.cnn.com/2019/07/02/americas/amazon-brazil-bo...

Why do you cut of the second part of this sentence? “Restoring trees at [low] density is not mutually exclusive with grazing. In fact many studies suggest sheep and cattle do better if there are a few trees in the field.”

Confusing. The rest of the article is like the second half. Not sure what the first half is doing there. Was that what they previously thought?

Re: Many more trees could be planted without encroaching on crop land or urban areas

#48

Post by senorjazz »

jillesvangurp wrote: post #46

It can actually be better than this still. Cattle can be part of a solution to helping restore arid land where the soil has been destroyed by intensive farming and erosion. Healthy soil stores enormous amounts of biomass (aka carbon). Intensive farming has destroyed enormous amounts of land world-wide and turned it into desert, releasing lots of CO2 into the atmosphere. This is a reversible process and catlle is part…

Is this actually validated?

Living in an area heavily deforested for cattle grazing, the cattle grazed land does not look like a healthy land. The cattle keep all plant life cut right back. Hot sun can easily access the soil drying it out, then when heavy rains come, the top soil all runs off the land.

Land that is left without cattle fares better, land that is actively reforested and trees helped to get established looks infinitely more healthy.

Re: Many more trees could be planted without encroaching on crop land or urban areas

#49

Post by skosch »

Retric wrote: post #42
jwr wrote: post #12

Earlier quoted context omitted.

> Economists widely agree that carbon pricing is the most effective way to fix climate change That is true, and does not conflict with the findings of the article. I think the difference here is that we can start planting trees right now. Carbon taxation is something people still pretend doesn't have to be done. It's also worth noting, that given the accelerating pace of the climate crisis, the time to start planting…

Most people are overestimating the value in planting trees. Trees readily plant themselves in areas they are well adapted to. Areas that don’t quickly turn into forests are generally poorly suited to growing trees. Further, not all trees are equivalent with marginal areas generally resulting in small and often very slowly growing trees.

> Trees readily plant themselves in areas they are well adapted to.

I am very skeptical if that's true – see formerly forested areas like Iceland, Brazil, etc. It's not easy for a single sapling to grow into a tree, even if the conditions are right. That's why companies like Afforestt exist [0].

[0] http://www.afforestt.com/

Re: Many more trees could be planted without encroaching on crop land or urban areas

#50

Post by skosch »

mariushn wrote: post #26
notatoad wrote: post #21

Earlier quoted context omitted.

I believe carbon pricing has two aspects - one is to charge carbon emitters, the other aspect is to use that money to do something that reduces existing CO2 levels. Just charging emitters does not completely solve the problem, so research into the best ways to spend the funds generated by carbon pricing is critical.

I always thought that carbon/green certificates taxes go towards environment/renewable energy, but I'm probably too naive... How to minimize the Tragedy of the commons effect? Where countries don't want to impact their economic growth because other countries won't impose such taxes, therefore some production will move there.

Good question. The answer lies in multilateral agreements (Paris etc.) and in so-called Border Carbon Adjustments. The latter have to be implemented carefully so as not to violate any WTO rules [0], but it's possible.

[0] https://www.brookings.edu/wp-content/uploads/2018/07/TPC_201...

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