• naevaTheRat@lemmy.dbzer0.com
      link
      fedilink
      English
      arrow-up
      3
      ·
      7 months ago

      Good question. The answer technically is maybe! however a few caveats.

      Charcoal washes away into the ocean where it mysteriously disappears https://www.sciencedaily.com/releases/2013/04/130419160715.htm it seems to enter the carbon cycle rather than get fixed. So maybe we could prevent that if we buried it very deep and sealed it in. Remember we are looking for a centuries long solution.

      In practice: charcoal compacted has a density of like 1.5 g/cm3 coal is about 1.8. They’re both mostly carbon, we would need to bury a loooot of charcoal. We have dug up and burned tens of billions of tonnes, that is a lot of charcoal to bury and not just in the sort of open cut surface mines coal is usually excavated from.

      Further making charcoal costs energy, even if you fuel it with the wood you’re processing. It’s a staggeringly expensive prospect to make billions of tonnes. There are around 280 billion tonnes of carbon that need fixing, that is just atmospheric. Significant portions are dissolved in the ocean and would start to come out as we reduced atmospheric carbon.

      Carbon fixation is an unimaginably large project, we would need cheap fusion and decades to make it practical. Essentially you want to reverse the energy consumption of everyone on earth for the last 200 years, it just isn’t realistic.

      For the few thousands of years we’re pretty much stuck with whatever we emit. Barring massive technological changes that are unforseeable