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A global reforestation project is how we fix climate change

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Re: A global reforestation project is how we fix climate change

#51

Post by tafurnace »

triclops200 wrote: post #8

That only "fixes" climate change as long as the trees continue growing and do not die. When dead, trees release their CO_2 that they've sequestered back into the atmosphere due to decomposition. Therefore, assuming those forests stay around, you've only delayed the problem by sinking a fixed amount of CO_2 away into the living biomass of the trees. The only way to make that a permanent sink would be to biochar the tr…

I personally believe that forests provide a net positive in terms of CO2 scrubbing regardless of decay/decomposition. The only evidence I'd offer is a time lapsed NASA video[0] showing CO2 emissions heatmap over time. The areas like the Amazon clear up the CO2 on a daily and seasonal basis. The areas where forests are impossible like the Arctic, it does not. The sun drives the cyclical "heartbeat" effect you see from day to day on the video, where plants using photosynthesis in the day (and macroscopically, the summer) effects the intensity of scrubbing moreso.

Also, maybe it is my mind's desire to simplify of all of it, but it was eye opening for me, and seemed obvious upon seeing that video, that forests were the key player in air management globally, and industrialized nations were the main drivers behind CO2 production in the air globally.

[0]: https://m.youtube.com/watch?v=x1SgmFa0r04

Re: A global reforestation project is how we fix climate change

#52

Post by ainiriand »

SketchySeaBeast wrote: post #49
seren wrote: post #40

Earlier quoted context omitted.

A sequoia sempervirens lives 1,500 years. I am not deluding myself that we will mitigate climate change by covering Earth in sequoia, but still that gives some timescale on how long trees can live. If we could mitigate climate change for another 1,500 years we would probably have found some other mitigations by then.

I fully support any plan that ends in the forest moon of Endor. What are even the odds we'd have fossil fuels left to burn in 1,500 years? I feel like we can safely say we'd have reached peak oil by then.

Great comment and even better concept.

Re: A global reforestation project is how we fix climate change

#55

Post by [deleted] »

drderidder wrote: post #38
triclops200 wrote: post #8

That only "fixes" climate change as long as the trees continue growing and do not die. When dead, trees release their CO_2 that they've sequestered back into the atmosphere due to decomposition. Therefore, assuming those forests stay around, you've only delayed the problem by sinking a fixed amount of CO_2 away into the living biomass of the trees. The only way to make that a permanent sink would be to biochar the tr…

That's basically, well, not true. When trees break down they contribute to soil organic matter. Approx 58% of SOM is carbon (SOC) making soil one of the largest carbon sinks on the planet. See https://en.wikipedia.org/wiki/Soil_organic_matter

[deleted]

Re: A global reforestation project is how we fix climate change

#56

Post by jcfrei »

A very interesting proposal. Given the current ultra low interest rates all the costs could be directly monetized by the central banks (via "climate bonds"), rather than making governments pay or introducing helicopter money when the next recession hits. We just need some key to distribute the resulting jobs and manufacturing orders between the countries.

Re: A global reforestation project is how we fix climate change

#57

Post by praptak »

ulrikrasmussen wrote: post #29
Ndymium wrote: post #14

Earlier quoted context omitted.

But when the trees die, new trees will grow in the same area, sequestering more or less that CO2 that was emitted from the dying tree, no? Would this not turn the forests into a permanent CO2 sink, at least on a rough scale? Or do they sequester less than they emit?

I unfortunately can't find a reference, but I heard that it takes about 20 years for a newly planted tree to peak with regards to absorption of carbon, and after about 100 years it reaches equilibrium where the forest emits about the same amount of carbon to the atmosphere as it absorbs (through decaying matter, fallen trees, and whatnot). It of course depends on the type of tree.

I think it's best to look at this as mass preservation problem. Trees absorb CO2 from air and store in their bodies. Once they die, the CO2 gets released.

Since there's a limited tree mass per area unit that the ground can support, once you reach that mass the input and output need to zero out, since there's nowhere to store any additional CO2.

Re: A global reforestation project is how we fix climate change

#58

Post by natch »

SketchySeaBeast wrote: post #49
seren wrote: post #40

Earlier quoted context omitted.

A sequoia sempervirens lives 1,500 years. I am not deluding myself that we will mitigate climate change by covering Earth in sequoia, but still that gives some timescale on how long trees can live. If we could mitigate climate change for another 1,500 years we would probably have found some other mitigations by then.

I fully support any plan that ends in the forest moon of Endor. What are even the odds we'd have fossil fuels left to burn in 1,500 years? I feel like we can safely say we'd have reached peak oil by then.

I don't know the source other than Elon Musk stated it in one of his presentations, but according to him we have five times as much fossil fuel reserves as we would need to utterly destroy ourselves with climate change. If that's right, waiting until we run out is not a solution. I realize the context was mentioning some speculation that we could push the timeline out some by planting trees. That speculation aside, we can't just wait for the oil to run out and be fine.

Re: A global reforestation project is how we fix climate change

#60

Post by arethuza »

growlist wrote: post #37
ainiriand wrote: post #22

Earlier quoted context omitted.

I was in shock to discover how empty and barren Ireland is. According to Wikipedia it is one of the most heavily deforested countries in Europe...

If you think that's bad: Ireland are still digging and burning peat to produce energy - Peat! in 2020! Horrifying

My parents used to burn peat in Scotland when I was growing up - probably why I'm particularly fond of some products flavoured by peat smoke...
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