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Grow plants. Cut them down. Bury them in old coal mines. Repeat. I think you can get something like 3 tons of CO2 per acre per year with switchgrass. There's a

by ars 6y ago

Grow plants. Cut them down. Bury them in old coal mines. Repeat. I think you can get something like 3 tons of CO2 per acre per year with switchgrass. There's around 1 trillion excess tons of CO2 in the atmosphere. Let's say we use around 200 million acres of land, that works out to: (1 trillion tons / 3 tons per acre per year) / 200 million acres = 1512 years. But that's just the US. If other countries help with land, we could probably get 1 or 2 billion acres involved, so that drops it to 150 years. That's a lot, but not as bad as your picture.

ajnin 6y ago
Do you have a study of this idea? At first glance it seems that the problems of fermentation, transportation, and resources needed to produce at that scale would be too large to overcome.
- ars 6y ago
  I do not. I made it up since I think it could work. Most studies assume the switchgrass will be burned in place of coal (which still helps). Fermentation might not be a problem, I'm hoping the switchgrass would be harvested when very dry, to cut down on that. Grass for silage, (which ferments) is cut when green, but hay is dry and does not ferment. Transportation and resources would be something, yes, but if you take a look at what we've built to make use of hydrocarbons, I think we could manage.
hinkley 6y ago
Process it into material that will end up in structures or even landfills also sequesters a lot. The roots of plants to end up donating some carbon content to the soil, so it’s not just the above ground part that’s part of the equation.
robomartin 6y ago
This has been studied. It is likely the most promising idea. The problem is scale in terms of both plants and time. And, of course, energy. Growing trees is precisely how the planet regulated CO2 levels over the 800,000 years of data we have. And we can see precisely how long it takes to come down by 100 ppm. The answer is 50,000 to 100,000 years. And so the question becomes: How are we going to deliver results 1000x faster than that? On a human time scale rather than a geological scale. We can't. Because of the third dimension: Energy. You can't get something for less energy than what it took to create the problem in the first place. The energy that created this problem is unimaginably large and it was deployed over a scale of millions to billions of years, consuming a staggering amount of material to store it in the form of petroleum. We can't magically grow enough trees to "fix" it 1000x faster without energy and resources we likely do not have. And then there's the question of what happens with so much vegetation. Which, again, is answered by the 800,000 year ice core record: Huge continental scale fires that load-up the atmosphere with CO2. Here in California we have probably put so much CO2 in the atmosphere in the last several months that you would have to shutdown the economy for a year to compensate. Nature is violently heartless. It does not care about us and our toys. Plant a trillion trees and see what happens when a major forest fire burns across thousands of miles without us having any ability to control it. Not a simple problem. EDIT: Here's a good article on the reforestation idea: https://www.livescience.com/65880-planting-trees-fights-climate-change.html https://www.livescience.com/65880-planting-trees-fights-clim...

by ars 6y ago

ajnin 6y ago

Do you have a study of this idea? At first glance it seems that the problems of fermentation, transportation, and resources needed to produce at that scale would be too large to overcome.

ars 6y ago
I do not. I made it up since I think it could work. Most studies assume the switchgrass will be burned in place of coal (which still helps). Fermentation might not be a problem, I'm hoping the switchgrass would be harvested when very dry, to cut down on that. Grass for silage, (which ferments) is cut when green, but hay is dry and does not ferment. Transportation and resources would be something, yes, but if you take a look at what we've built to make use of hydrocarbons, I think we could manage.

hinkley 6y ago

Process it into material that will end up in structures or even landfills also sequesters a lot. The roots of plants to end up donating some carbon content to the soil, so it’s not just the above ground part that’s part of the equation.

robomartin 6y ago

This has been studied. It is likely the most promising idea. The problem is scale in terms of both plants and time. And, of course, energy. Growing trees is precisely how the planet regulated CO2 levels over the 800,000 years of data we have. And we can see precisely how long it takes to come down by 100 ppm. The answer is 50,000 to 100,000 years. And so the question becomes: How are we going to deliver results 1000x faster than that? On a human time scale rather than a geological scale. We can't. Because of the third dimension: Energy. You can't get something for less energy than what it took to create the problem in the first place. The energy that created this problem is unimaginably large and it was deployed over a scale of millions to billions of years, consuming a staggering amount of material to store it in the form of petroleum. We can't magically grow enough trees to "fix" it 1000x faster without energy and resources we likely do not have. And then there's the question of what happens with so much vegetation. Which, again, is answered by the 800,000 year ice core record: Huge continental scale fires that load-up the atmosphere with CO2. Here in California we have probably put so much CO2 in the atmosphere in the last several months that you would have to shutdown the economy for a year to compensate. Nature is violently heartless. It does not care about us and our toys. Plant a trillion trees and see what happens when a major forest fire burns across thousands of miles without us having any ability to control it. Not a simple problem. EDIT: Here's a good article on the reforestation idea: https://www.livescience.com/65880-planting-trees-fights-climate-change.html https://www.livescience.com/65880-planting-trees-fights-clim...