4 ms·

1. Plant trees 2. Cut down trees 3. Sink trees to the bottom of a great lake

sliken 7y ago
Sure, that works, and will continue to work. Forests on the other hand help when new, but reach a steady state. However the problem is that at least for the near future burning oil, making plastic, and similar other carbon intensive processes make it near impossible to plant enough trees. Carbon taxes, solar, wind, energy storage, and nuclear offer at least the possibility of offsetting carbon generation.... then plant and sink trees. I do wonder how hard it would be to make a widget that with sunlight could make pure carbon bricks that would be useful as a building material. I think Cory Doctorow described it in one of his sci-fi books. Ideally self replicating of course.
willj 7y ago
Trees take about 10 years[1] to reach their peak CO2 consumption. That’s a long time to wait. Also, trees and other plants seem to be decreasing in how much carbon they are absorbing, compared to what they did a decade ago. [2] [1] http://urbanforestrynetwork.org/benefits/air%20quality.htm http://urbanforestrynetwork.org/benefits/air%20quality.htm [2] https://cosmosmagazine.com/climate/trees-and-plants-reached-peak-carbon-10-years-ago https://cosmosmagazine.com/climate/trees-and-plants-reached-...
- quixoticelixer- 7y ago
  Not really, this is going to be a problem for a while
agumonkey 7y ago
you need very tall trees to suck co2 in the atmosphere
- FooHentai 7y ago
  explain please
  - quixoticelixer- 7y ago
    Because Co2 is high in the air and you need tall trees to reach it /s
vkou 7y ago
It's a lot less effort to just not burn whatever form of carbon put the CO2 in the atmosphere.
nullc 7y ago
If you do the math, this essentially doesn't work out. :( Trees are far too slow, even if you have a good way to lock up the carbon once the trees capture it. For an intuitive understanding, consider: Our surplus of CO2 comes (mostly) from burning fossil fuel that took millions of years for the original plant life to accumulate.
- sliken 7y ago
  Yes, but forests capture carbon quickly until the average age of the trees starts increasing. So zero to 50 years is good, but after that things really slow down. The amount of wood becomes relatively constant. So slowly, very slowly leaves fall/get eaten by bugs, break down, and get absorbed by new trees. But there is a net gain, just a very slow one. Then things like continents collide, mountain ranges come and go, and significant biomass gets buried and under pressure and time turns into oil/gas. So for scale we could cut down all trees and bury it and take 638 gigatonnes out of our ecosystem. Not sure of the average tree age, but assuming it was replanted we could likely repeat that every 20-30 years. The annual oil consumption looks to be around 36 billion barrels. Each weighs around 300 pounds. If my conversion is right that's about 4.9 Gigatonne. So burying all trees every 30 years would be about 21.2 gigatonne a year or enough to offset all oil consumption AND decrease our current levels to pre-industrial levels. Or we could just use less oil.
  - nullc 7y ago
    Consider the scale of what you're describing now: cutting down and burying all trees on earth every 30 years. We could certainly _burn_ all of them every 30 years, but that wouldn't help. The figure you need is the marginal capture after the emissions from the process. Wikipedia says our current emissions from fossil fules and cement production is estimated at 10GtC (not absurd compared to your numbers, since you count only crude oil). So restating, if somehow without adding any new carbon buried _all_ the vegetation on earth every 30 years, we'd remove 21 GtC per year or a net reduction of 11. To get back to pre-industrial levels it would still take 34 years even ignoring the >1000 GtC currently in the ocean surface that would come out of solution and fight the reduction. (I have no idea how to setup the diff eqs for solving for the ocean contributions...) The fact that an emission free removal and replacement of all vegetation of earth would still take a long time is basically my point around "planting trees" not being a sufficient plan. :) Not that planting trees is bad, but solving this is going to take some mixture of reduction and magic (presumably both the political and technological kind).

Sure, that works, and will continue to work. Forests on the other hand help when new, but reach a steady state. However the problem is that at least for the near future burning oil, making plastic, and similar other carbon intensive processes make it near impossible to plant enough trees. Carbon taxes, solar, wind, energy storage, and nuclear offer at least the possibility of offsetting carbon generation.... then plant and sink trees. I do wonder how hard it would be to make a widget that with sunlight could make pure carbon bricks that would be useful as a building material. I think Cory Doctorow described it in one of his sci-fi books. Ideally self replicating of course.

willj 7y ago

Trees take about 10 years[1] to reach their peak CO2 consumption. That’s a long time to wait. Also, trees and other plants seem to be decreasing in how much carbon they are absorbing, compared to what they did a decade ago. [2] [1] http://urbanforestrynetwork.org/benefits/air%20quality.htm http://urbanforestrynetwork.org/benefits/air%20quality.htm [2] https://cosmosmagazine.com/climate/trees-and-plants-reached-peak-carbon-10-years-ago https://cosmosmagazine.com/climate/trees-and-plants-reached-...

quixoticelixer- 7y ago
Not really, this is going to be a problem for a while

agumonkey 7y ago

you need very tall trees to suck co2 in the atmosphere

FooHentai 7y ago
explain please
- quixoticelixer- 7y ago
  Because Co2 is high in the air and you need tall trees to reach it /s

vkou 7y ago

It's a lot less effort to just not burn whatever form of carbon put the CO2 in the atmosphere.

nullc 7y ago

If you do the math, this essentially doesn't work out. :( Trees are far too slow, even if you have a good way to lock up the carbon once the trees capture it. For an intuitive understanding, consider: Our surplus of CO2 comes (mostly) from burning fossil fuel that took millions of years for the original plant life to accumulate.

sliken 7y ago
Yes, but forests capture carbon quickly until the average age of the trees starts increasing. So zero to 50 years is good, but after that things really slow down. The amount of wood becomes relatively constant. So slowly, very slowly leaves fall/get eaten by bugs, break down, and get absorbed by new trees. But there is a net gain, just a very slow one. Then things like continents collide, mountain ranges come and go, and significant biomass gets buried and under pressure and time turns into oil/gas. So for scale we could cut down all trees and bury it and take 638 gigatonnes out of our ecosystem. Not sure of the average tree age, but assuming it was replanted we could likely repeat that every 20-30 years. The annual oil consumption looks to be around 36 billion barrels. Each weighs around 300 pounds. If my conversion is right that's about 4.9 Gigatonne. So burying all trees every 30 years would be about 21.2 gigatonne a year or enough to offset all oil consumption AND decrease our current levels to pre-industrial levels. Or we could just use less oil.
- nullc 7y ago
  Consider the scale of what you're describing now: cutting down and burying all trees on earth every 30 years. We could certainly _burn_ all of them every 30 years, but that wouldn't help. The figure you need is the marginal capture after the emissions from the process. Wikipedia says our current emissions from fossil fules and cement production is estimated at 10GtC (not absurd compared to your numbers, since you count only crude oil). So restating, if somehow without adding any new carbon buried _all_ the vegetation on earth every 30 years, we'd remove 21 GtC per year or a net reduction of 11. To get back to pre-industrial levels it would still take 34 years even ignoring the >1000 GtC currently in the ocean surface that would come out of solution and fight the reduction. (I have no idea how to setup the diff eqs for solving for the ocean contributions...) The fact that an emission free removal and replacement of all vegetation of earth would still take a long time is basically my point around "planting trees" not being a sufficient plan. :) Not that planting trees is bad, but solving this is going to take some mixture of reduction and magic (presumably both the political and technological kind).