You are right.
But it’s less certain.
There’s a decent amount of carbon emissions associated with management of land, however, and if you want the land to continue to be optimised for carbon sequestration you’ll need to manage it and, besides, in most areas you can’t just buy land, plant some trees on and leave it - it’ll need active management to stay a forest and to comply with local regulation.
But let’s say you’re doing that and planting for carbon sequestration, then you’d probably choose something like pine (fast growing, absorbs a lot of carbon, stays green through the year so tends to prevent competition on the floor). A tree that like will absorb roughly a tonne (1000-1100 kg of carbon) in its life. Then it does and you’ll need to remove it to ensure a new tree can grow (otherwise it’ll be taken over by other species slowly).
A hectare of dense pine trees can probably hold 3000 trees (if we are being generous) so a hectare (100x100 metres of land) can hold 3000 tonnes of carbon. On average in Europe we emit about 9 tonnes of carbon per year and live for 80 years so a hectare can hold about 4 people’s worth of life time emissions.
In the U.K. you’ll end up spending about £25,000 for a hectare of woodland (give or take), but then you’ll need public liability insurance and management fees (let’s just say £20/year for for a hectare of insurance and £750/year for management of a hectare) … so let’s assume £800/year for a hectare or £200/year to manage the size of woodland required to absorb a person’s life time emissions (remember, 4 people per hectare). Now you need a trust manager who runs, permanently forevermore, to manage it all. Let’s say £40,000/year and assume that they manage 1000 people’s life time emissions (this obviously could scale down to almost zero as the scheme grew) or £40/year per person.
But don’t forget additionally: This has to be NEW woodland, so you need to buy non-woodland and then plant the woodland. Otherwise you’re not absorbing more carbon. Typical quotes for a hectare of pine planting will be about £4000.
And this cost needs paying forevermore: £6000 to buy the space for a person’s emission £4000 to plant it £250/year to manage it (insurance, management)
To deliver £250/year you’ll need an investment of 250/0.04=£6250. Let’s just say £7000 to leave some buffer for bad years and to pay for the additional carbon that’s emitted from the management. So:
£6000 to buy the space for a person’s emissions.
£4000 to plant it.
£7000 to manage it forevermore.
So all in you’ll need to spend £17000 to absorb your lifetime’s worth of emissions.
Now let’s compare that to geological sequestration. Climeworks, the only publically available scheme to suck carbon out of the air and sequester it into rock, permanently, quotes £1100/ton of carbon. So to extra the 720 tones you’ll emit in your lifetime it would be £792,000.
So yeah, trees do it a LOT cheaper (2% of the cost), but it requires active management and it’s not guaranteed to be on geological scale.
And I’m not aware of a scheme that enables this to happen. Are you?
jeffw@lemmy.world 7 months ago
Yeah, I mean I think carbon capture is kinda stupid on one level. It’s like an excuse for us to not change our behavior
jasondj@ttrpg.network 7 months ago
No. Carbon neutral isn’t enough. We are going to have to go carbon neutral.
We can’t just take hundreds of millions of years worth of sequestered carbon and dump it into the atmosphere and leave it there to re-sequester itself. That’s going to take a long time to reverse enough to even buck the current trend of global warming, if we were able to just go carbon neutral today.
metaStatic@kbin.social 7 months ago
not only do we need to be carbon negative but we need to move and store more volume than any industry in history ... or is it all industry in history. the idea is absurd either way.
makyo@lemmy.world 7 months ago
It is a historically unprecedented and utterly necessary project. Only a combination of all of the above can even get us close. It’s way too late to be choosy.
Crashumbc@lemmy.world 7 months ago
Yeah, this is like the inventor that wanted to use floating booms to clean up the ocean… Totally impossible
makyo@lemmy.world 7 months ago
I keep hoping some smart environmentalist/entrepreneurs figure out more markets for sequestered carbon. For example how we can use more wood in construction. I just can’t see the right kind of social change happening before it’s too late so hopefully there’s a way to capitalism our way out of this.
jasondj@ttrpg.network 7 months ago
I essentially just said the same thing in another reply before I read this one.
I don’t think growing more trees for sequestering is, alone, going to work, due to the sheer scale. Growing trees itself is great. We should totally do that. But for the purpose of sequestering carbon long-term, it’s not that great.
Best we could hope for is a method to discover some new building material that we could manufacture directly from captured atmospheric carbon. Then there is a downstream market for it and the carbon gets “sequestered” as part of our economy of durable goods. Like an alternative to wood, or copper, PVC/PEX, or cement, or steel studs, or rubber, or concrete, or plastic, or hell even girders.
Yaztromo@lemmy.world 7 months ago
Unless humans get involved and harvest and sequester the tree remains themselves.
jasondj@ttrpg.network 7 months ago
Then there still is still a need to expend tons of energy disposing it in a way to not have it re-release in a few hundred thousand years.
The scale is insane to comprehend. We would essentially have to manufacture the equivalent of every pound of coal that’s ever been burned to get to pre-industrial levels, while also consuming as little fossil fuels as possible. I do not think it is possible to do so with trees alone unless we have a lot of cheap green power. Because ultimately some entity, be it government or corporation or philanthropist, will have to pay for it.
And then there is the issue of land rights for where you’re gonna dump all of the captured carbon. That’s a problem either way. I hope we start discovering some new post-space-age reclaimed-carbon-based building materials. That’s probably the best we could hope for. Then there is a huge downstream market for captured carbon which means way less ancient carbon being pulled up into the cycle.
I’m not poo-pooing this technology. It’s super important for us to invest and scale up carbon capture methods. But it can’t be expected to be immediately economically viable.
JeffKerman1999@sopuli.xyz 7 months ago
I thought this hypothesis was disproved and it was some geological process that buried the trees? I remember there was a study about lignin content in other fossils and it was compatible with fungi decomposing wood.
ChaoticNeutralCzech@feddit.de 7 months ago
The trees got buried in oxygen-free peat bogs where decomposers could not survive.
ChaoticEntropy@feddit.uk 7 months ago
Don’t worry, we replaced all the forests with CarbVac™️ facilities. Ensuring a brighter tomorrow, but only if we’re the ones doing it.