[cyphertruck]

Economics rules everything. How much does this cost vs simply planting trees, when the value of harvesting the trees is included? Since tree farms are generally profitable, and wood is expensive, it seems this method is likely to be economically less efficient.

[roflmaostc]

The problem is you cannot plant enough trees around the globe to offset our CO2 emissions. Also, a forest only absorbs CO2 while alive. Once it dies, it emits CO2 too. You would need to permanently store the wood somewhere (submerging in water, etc).

Recent article: https://www.theguardian.com/environment/2025/nov/28/africa-f...

[manoDev]

Planting trees solves both the carbon capture and the emissions issue from different angles. Some examples are:

- With more wood available it’s more economical to use it as a building/manufacturing material over other emissive sources (concrete, steel, plastic)

- We can replant the same area multiple times

- Even if we plant crops for biofuels, it’s closer to carbon neutral than burning fossil anyway

Every move we can make towards planting (and managing) more of the surface of the Earth is an improvement, without waiting for miraculous new technology.

[cogman10]

It's possible to permanently capture the carbon if you turn the wood into charcoal and ultimately bury or store that.

But left out to rot and yeah, the fungus and bacteria will ultimately consume the wood and release CO2 as a byproduct.

[dylan604]

If these forests are planted by humans, why do we think the dead trees would just be left to rot like you suggest vs being harvested for wood? The logic does not compute other than trying to make a ridiculous point.

[adregan]

One little appreciated fact is that trees also respirate CO2 when they are cracking their stored sugars produced via photosynthesis. So they don’t sequester all of the CO2 that they consume.

[xnx]

Biochar seems like a good option

[nephihaha]

Trees have advantages that go beyond bureaucratic aspects of environmentalism.

[yodon]

>Economics rules everything

Physics rules everything, once you start trying to run at scale.

The density of carbon per unit volume in solid materials of interest doesn't vary that much, whether you sink it in trees or in exotic materials like diamonds. That means you can calculate the volume of material required so sink a desired amount of atmospheric carbon.

If you want to have a measurable impact on the atmosphere, say dialing it back to 1980 CO2 levels, you're talking not about making a pile of stuff but about making a mountain range that's a mile high and hundreds of miles long.

Now figure out how many trucks you're going to need to move that much material from where your sequestering machine is to where your pile of stuff is.

Or if you want to dump that material in the ocean (which someone else will certainly object to), extend your calculation to figure out how many container trucks worth of material you need to dump into the ocean every hour to accomplish your atmospheric cleanup in whatever amount of time you choose (a decade? If it takes a century, that's not fast enough).

And finally think about surface to volume ratios. You're trying to sink it into a volume, but you can only get the gas into the volume through its surface, so the speed of your process is limited by surface area.

If you want to do it with trees, my personal spitball estimates are that you probably need to plant somewhere between the entire state of Connecticut and the entire state of Colorado to have the kind of impact one would want (there's more subtlety to tree calculations than one generally likes to admit, so feel free to come in with way higher numbers than I did).

Which brings us back to economics. If you have a well-managed forest of that size and scale, someone is eventually going to come along, maybe in 100 years, maybe in 500 years, and say "hey if we cut this down, we could burn the wood to heat our homes" and all that carbon goes back into the atmosphere, so you actually need to sink it into something that is energetically unfavorable for recovery, which means you also need to expand a huge amount of energy to sink the carbon into that energetically unfavorable state.

[tzs]

If we took all the CO2 out of the atmosphere and converted the C into graphite and spread that uniformly over the top 10 subtropical deserts it would be around 2 cm deep.

This suggests a long term approach of building solar powered carbon capture plants in subtropical deserts, they capture it and convert to graphite, which is then spread out under the solar panels.

I once did the math on this, using the specs for currently available solar powered carbon capture, and it came out to something like if we used 100 years worth of the current production annual production of solar panels for this we could carbon capture at a rate that could drop the atmosphere from current levels of CO2 to pre-industrial levels in a few years even if we do not reduce emission rates.

So...not practical now, but might be feasible as a very long term project that over many decades builds out enough capacity to get things under control as long as we can keep everything from going to hell over that time.

[marcosdumay]

> you're talking not about making a pile of stuff but about making a mountain range that's a mile high and hundreds of miles long.

Just to put it into numbers, wikipedia has the total amount of CO2 on the global warming page, if we assume it's in a 2 kg/l substance it totals to around 180 km^3.

[sokoloff]

If we pull this off, I would not expect people 500 years from now to undo it.

[Yizahi]

In the order of importance:

1. Even if we do magic and emit nothing, we still need to remove CO2 from the atmosphere or it will cook us over time, just longer.

2. We would need an enormous area for forests (which i great), which would mean a lot of intervention, like resettling people, demolishing and constructing new buildings, a lot of machinery time to move people to and from the new forests, a lot of planting and forest maintenance involved. And add he work to cut and bury resulting wood. If you would sum all the incidental emissions from this process it would rapidly become much less efficient (if at all).

Without either CO2 capture or a sun shade of some sort, the CO2 levels and temperature will only ever increase, just like now.

[jacquesm]

> it will cook us over time, just longer.

The largest sous-vide cooking pot ever...

[gus_massa]

I agree. Plants are not very efficient (1% or 2%) but they include packaging the CO2 in a stable form. You can store the grain or wood for long periods of times.

In this case, it looks like they get CO2 as a gas. It's cheaper because you don't have to use energy to undo the burning, but it's difficult to store for a long time.

(I'm not sure if someone tried to make a fake underground bog in abandoned mine. Just fill with wood and water to keep the oxygen low and make the wood decompose slowly.)

[cjbenedikt]

Take a look at "wood vault". 'Wood vaulting': A simple climate solution you’ve probably never heard of | Grist https://share.google/lS8xnMGEd1pMzlNg2 Economically not attractive but apparently very efficient in locking up CO2.

[dheera]

> stable form

Not really, forest fires happen and then a few hundred of years of sequestered CO2 gets released back in an instant.

Organic material with oxygen gas floating around is not stable.

Sequestering carbon into the ocean might be a better strategy. Not flammable and not subject to stupid capitalism effects around land prices.

[S3verin]

Planting trees is not effective since it takes decades to capture the carbon, but the next years are crucial for determining long term climate developments.

[adammarples]

There is no carbon capture technology on earth that can be rolled out at a scale over the next few years that can compete with planting trees. Especially not one that has just been invented in one university. Ash grows 90cm per year, that's all carbon. Scale that to millions and billions.