• _different_username@lemmy.world
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    3 months ago

    Of course, trees should be planted, but the notion that they are an expedient way of decarbonizing the atmosphere is plainly wrong. Had nature optimized plant life to remove carbon from the atmosphere, there would be no CO2, no plants, and the planet would be a snowball instead of the vibrant, warm (too warm) climate we have today. Nature maintains stasis - and therefore life - by avoiding carbon sequestration.

    You may have seen the Keeling Curve, the “graph of the accumulation of carbon dioxide in the Earth’s atmosphere based on continuous measurements taken at the Mauna Loa Observatory on the island of Hawaii from 1958 to the present day.” Notice that it goes up and then down in Seasonal Variation. This is because, during the summer months in the Northern hemisphere, all the plant life decarbonized the air to form new leaves and greenery. Then, in the winter, all the leaves fell back to the ground where they were consumed by fungi and detrivores and converted back to CO2.

    Suppose we stopped producing fossil fuels tomorrow. The Keeling Curve would still have seasonal variation, but it would be against a constant mean, rather than the current rising one. If we then just planted more trees, the seasonal variation would increase, perhaps, but the mean would remain more or less constant. While beneficial, none of the planting would make more than a dent in the hundreds of billions of tons of anthropogenic CO2 in the atmosphere. The potential for soil sequestration is on the order of 1 Gt/year.[source] That doesn’t mean we shouldn’t practice sustainable agriculture and forestry, rather we should, but it won’t reduce our carbon debt or start to reverse climate change. Believing that it will is just magical thinking, coincidentally an inadvertent implication of the meme.

    Given that nature is (almost) perfectly inefficient at long-term carbon sequestration, it would seem that effective, long-term decarbonization of the atmosphere on any scale short of millennia has to include mechanical means, no matter how inefficient such means may appear.

    • Ephera@lemmy.ml
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      3 months ago

      The thing is, you and everyone arguing against me here, have yet to offer a concrete solution that’s better. I don’t care how futile trees might be, they’re the most efficient, most scalable solution that I’m aware of. And not doing anything due to trees being futile, that’s completely fucking pointless, too. If we die, we might as well die fighting, even if it merely makes the remaining years just a little less bad.

      • _different_username@lemmy.world
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        3 months ago

        You make a good point. If there were no potential solution, trees (i.e. sustainable agriculture) would be the best solution. It would take a few hundred years but we would get back to pre-industrial levels at zero emissions.

        The potential solution is direct air capture. Although there are many forms, I am fond of the method proposed by Klaus Lackner. By making a large number of CO₂ scrubbers, as opposed to a few very large ones (like Climeworks), the economics of carbon removal get very easy, very fast.

        A 1 m² area that gets an average 2 m/s breeze through it sees about a gram of CO₂ pass through every second. This is about 100 kg of CO₂ per day. So let’s make a machine that catches CO₂ from a 2 × 5 m area and catch 1 t per day, or 300 t per year. For this machine to pay off its carbon debt, it’s going to need to be around for a while, say 10 years. What happened during those 10 years? 3 kt went out of the atmosphere for good. If you liquefied the CO₂, this would fill 3 McMansions.

        Lackner seems to think we can build this machine for $100k. Now we have a price of $30/t of CO₂ captured. As it stands, we need to get about 1,000 Gt of CO₂ out of the atmosphere to stabilize the climate, so we need to build $30T worth of these machines. How could we possibly afford that? Well, we would spend ~$1T on this per year for about 30 years.

        Where would that kind of money come from? Sacrifices would be needed, it’s true. I think the biggest would be giving up on war. Global defense budgets add up to this scale of funding, and if the nations of the world decided to put an end to war, we could use the peace dividend to pay for the restoration of the climate. Perhaps there wouldn’t be any other sacrifices needed at all.

        If this seems unrealistic to you, that’s ok too. We can still keep war and do things the slow way or (more likely) not do them at all. I suppose a decade-long nuclear winter would also do wonders for global cooling and emission reductions. Personally, though, I would prefer world peace and direct air capture to stabilize the climate.

        I think, from your post, you would agree. If we are going to fight, we should fight climate change, not each other, no?