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jhansen858 t1_j94wdbu wrote

Reply to comment by try_cannibalism in MIT team makes a case for direct carbon capture from seawater, not air by MotorDrive

do you have a source for this? seems hard to believe since it takes about 5 minutes to plant a tree.

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try_cannibalism t1_j94wz9r wrote

Source: planting trees is my job.

  1. All but a tiny percentage of trees are planted for forestry. They're planted as a crop, to be harvested.
  2. The amount of F350 fuel and helicopter fuel to get me to work and back each day is not insignificant
  3. Even if 100% of the biomass of the trees, once cut, was used for wood products and never biodegrade, that's only just carbon neutral, if you pretend those helicopters and f350s and logging trucks don't exist.
  4. Forestry is incredibly wasteful, a large portion of biomass is cut and left to biodegrade or gets burned. Burning is better because it releases no methane which is a much more powerful greenhouse gas.
  5. Carbon is released from the soil when forests are cut, not just the tree. Not even sure if that gets replenished by a tree farm between cuts.
  6. Bonus: for a pro it's more like 6 seconds per tree all day long not 5 minutes, but that doesn't change the above
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zosolm t1_j96mr18 wrote

Just to nitpick point 3; disregarding the helicopters and trucks, if the wood never biodegrades isn’t that permanent sequestration rather than just carbon neutral?

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try_cannibalism t1_j9888kl wrote

If you're making new forests our of desert, it could be considered permanent sequestration if you assume none of the biomass will biodegrade, be burned, harvested, or otherwise released.

If you harvested 100% of the biomass and locked it away in a non-biodegradable product, like concrete.

But 99% of the time, you're only replanting the forest that was cut last year, most of the biomass is wasted, and all the products are either immediately consumable or eventually break down (how many wood buildings/furniture products even last 100 years these days?)

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