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This is a thermodynamically losing proposition for a human industry - liberating carbon is enthalpically and entropically favorable. Sequestering it requires pu

This is a thermodynamically losing proposition for a human industry - liberating carbon is enthalpically and entropically favorable. Sequestering it requires putting the genie back in the bottle, and where will the energy budget for that come from? Fortunately there is a system to do this which dwarfs in scale pretty much any industry humans ever have and ever will come up with: photosynthesis. While 10 Gigatons of C is a lot, terrestrial biomass is ~600 Gigatons of C. The best strategy for reversing carbon emissions is letting the Earth soak it back up again.

colechristensen 8y ago
These are my thoughts: we need to water the desert and fertilize the oceans. Use wind, solar, and biomass powered generators to desalinate water and pipe it inland. Pick locations that would have local positive rainfall feedback. Pump oxygen into deadzones caused by nutrient runoff encouraging algal blooms. Either harvest it or let it die and sink to the bottom of the sea.
- roryisok 8y ago
  The problem in that solution is the "we" part. There is no global authority to take the responsibility or initiative, and nobody who wants to front the cost. It's so stupid that we have the technology and knowledge to save our species and civilisation but our imaginary number system won't let us.
adrianN 8y ago
Photosynthesis is only about 1% efficient and you'd have to store the biomass in a form that doesn't decompose (e.g. as coal). It might be possible to improve this.
- godelski 8y ago
  > you'd have to store the biomass in a form that doesn't decompose Which for everyone that doesn't know, this is why if even today we stopped net greenhouse production world wide the planet would still warm. Because there is biomass underneath the ice that will (is) be(ing) released as it melts.
- pmiller2 8y ago
  It is possible to improve the efficiency of photosynthesis by 25-40%. I wish I had a journal article, but here’s a news article about the process: https://www.latimes.com/science/sciencenow/la-sci-sn-more-efficient-photosynthesis-20191003-story.html https://www.latimes.com/science/sciencenow/la-sci-sn-more-ef...
  - maxerickson 8y ago
    That means you go from 1% efficient to 1.5% though.
- barry-cotter 8y ago
  Mass production of biochar and use it as a soil amendment. Sequesters carbon in production, sequesters more in the soil as it encourages biomass formation and encourages even more as plants grown in such soil do better. https://en.wikipedia.org/wiki/Biochar https://en.wikipedia.org/wiki/Biochar > Biochar is charcoal used as a soil amendment. Biochar is a stable solid, rich in carbon, and can endure in soil for thousands of years.[1] Like most charcoal, biochar is made from biomass via pyrolysis. Biochar is under investigation as an approach to carbon sequestration,[1] as it has the potential to help mitigate climate change.[2][3][4] It results in processes related to pyrogenic carbon capture and storage (PyCCS).[5] Independently, biochar can increase soil fertility of acidic soils (low pH soils), increase agricultural productivity, and provide protection against some foliar and soil-borne diseases.[6]
  - roryisok 8y ago
    This passage caught my eye : > Researchers have estimated that sustainable use of biocharring could reduce the global net emissions of carbon dioxide (CO 2), methane, and nitrous oxide by up to 1.8 Pg CO 2-C equivalent (CO 2-Ce) per year (12% of current anthropogenic CO 2-Ce emissions; 1 Pg=1 Gt), and total net emissions over the course of the next century by 130 Pg CO 2-Ce, without endangering food security, habitat, or soil conservation. It feels like every other week I read about one approach which has the potential to save us from climate change, if scaled correctly. Suberin rich food crops. Autonomous ships that produce artificial clouds. Biochar. Painting things white. Olivine rock weathering. Greening the Sahara. I don't believe any of these solutions alone is going to save the planet, but surely doing several in concert would help
- astazangasta 8y ago
  The efficiency doesnt matter - solar inputs are ubiquitous and require no effort on our part.
  - 205guy 8y ago
    This. Anything else requires energy input (and thus carbon emissions in the current situation), whereas plants are carbon-negative from the get-go, require no effort, and just work right now (no tech to wait for, just a few more years...). Yes, plants eventually decompose and release the carbon, but every new plant buys us 10-100-1000 years until we have to deal with that carbon. The biggest problem now is finding land to reclaim with forest and preventing existing forest from being cut down (as pointed out in other comments, the mature trees store more carbon per area than new trees). In the end, our forests are competing against our agriculture and food supply (and growing population). Just like energy efficiency (home insulation and sealing) is the low hanging fruit of energy conservation, reducing the consumption and production of low-land-efficiency foods like meat is the easiest way to reduce agricultural footprint and make more available to carbon-sequestering trees.
gizmo686 8y ago
Natural cycles are approximately carbon neutral; that is why Earth has not become an iceball yet [0]. Over the very long terms, some carbon can get sequestered, which is how we got fossil fuels in the first place. But consider how long it took nature to sequester all of that carbon. Now that we have reintroduced it into the system, there is no natural mechanism to just take it back out again. We could change the steady state slightly by increasing biomass; but that would only offset the carbon added by the destruction of said biomass, and cannot scale beyond the available space (and all other natural limitations on how much life can be put in one spot). If we did come up with a way for Earth to just "soak it back up again" that was based on seeding some type of organic and letting it work for us, I would be extremly concerned about a global cooling catastrophe. There is no natural stop point at the carbon concentrations we want, and if we overshoot the amount we pull out, we are in for a very bad time. (Not to mention the other environmental effects that the resource sink we introduce will have. I doubt carbon would be the only resource it hogs.) [0] It did come close with the emergence of photosynthesis. At the time, photosynthesis was decidedly not carbon neutral, as there was no counter force to consume oxygen until the emergence of aerobic organisms. https://en.wikipedia.org/wiki/Great_Oxygenation_Event https://en.wikipedia.org/wiki/Great_Oxygenation_Event
- astazangasta 8y ago
  Much of our carbon contribution comes from deforestation, soil erosion, etc. In other words, habitat loss and conversion. For example, there used to be forestation across much of the "Fertile Crescent" before we had our way. Manhattan was a thousand year growth forest before Europeans showed up. Removing the dead hand of man from the scale can do much to reverse this process; actively fostering reforestation (see: Dune) can do more. We are over budget here - putting 1000 gigatons of C back is going to be tough. But putting a good chunk of that away is probably the result of something like: humanity stops eating meat and reduces its agricultural footprint, commits most of the earth to nature preserves.
  - 205guy 8y ago
    I wonder why you're being downvoted, maybe people don't want to face the consequences of their actions. Though I think we don't need to be so absolute in terms of "stops eating meat," that's hard for people to handle. It would be easier to convince people and still extremely effective to reducing meat consumption to once a week and on holidays, like in the old days.
remarkEon 8y ago
>The best strategy for reversing carbon emissions is letting the Earth soak it back up again. Not really sure what you're referring to, if we're being practical. The only proposal I've seen that uses your strategy is seeding the oceans with iron oxide to cause algae blooms. I don't really know if that's truly feasible (or desirable) but it is the only one I've heard that is an honest attempt at Geo-engineering our way out of this mess.
- roryisok 8y ago
  Didn't someone try this in Canada with disastrous results?
  - ben_w 8y ago
    It’s been tried repeatedly. Iron isn’t the only limit on algal blooms, though it is often the most relevant. I think the main problem is control over which species bloom, partly to avoid toxic bloims near fishing areas, but also as you want something that sinks the carbon rather than floating it.
agumonkey 8y ago
pardon the moonshot.. solar powered drone aggregating CO2 in the atmosphere ?

colechristensen 8y ago

These are my thoughts: we need to water the desert and fertilize the oceans. Use wind, solar, and biomass powered generators to desalinate water and pipe it inland. Pick locations that would have local positive rainfall feedback. Pump oxygen into deadzones caused by nutrient runoff encouraging algal blooms. Either harvest it or let it die and sink to the bottom of the sea.

roryisok 8y ago
The problem in that solution is the "we" part. There is no global authority to take the responsibility or initiative, and nobody who wants to front the cost. It's so stupid that we have the technology and knowledge to save our species and civilisation but our imaginary number system won't let us.

adrianN 8y ago

Photosynthesis is only about 1% efficient and you'd have to store the biomass in a form that doesn't decompose (e.g. as coal). It might be possible to improve this.

godelski 8y ago
> you'd have to store the biomass in a form that doesn't decompose Which for everyone that doesn't know, this is why if even today we stopped net greenhouse production world wide the planet would still warm. Because there is biomass underneath the ice that will (is) be(ing) released as it melts.
pmiller2 8y ago
It is possible to improve the efficiency of photosynthesis by 25-40%. I wish I had a journal article, but here’s a news article about the process: https://www.latimes.com/science/sciencenow/la-sci-sn-more-efficient-photosynthesis-20191003-story.html https://www.latimes.com/science/sciencenow/la-sci-sn-more-ef...
- maxerickson 8y ago
  That means you go from 1% efficient to 1.5% though.
barry-cotter 8y ago
Mass production of biochar and use it as a soil amendment. Sequesters carbon in production, sequesters more in the soil as it encourages biomass formation and encourages even more as plants grown in such soil do better. https://en.wikipedia.org/wiki/Biochar https://en.wikipedia.org/wiki/Biochar > Biochar is charcoal used as a soil amendment. Biochar is a stable solid, rich in carbon, and can endure in soil for thousands of years.[1] Like most charcoal, biochar is made from biomass via pyrolysis. Biochar is under investigation as an approach to carbon sequestration,[1] as it has the potential to help mitigate climate change.[2][3][4] It results in processes related to pyrogenic carbon capture and storage (PyCCS).[5] Independently, biochar can increase soil fertility of acidic soils (low pH soils), increase agricultural productivity, and provide protection against some foliar and soil-borne diseases.[6]
- roryisok 8y ago
  This passage caught my eye : > Researchers have estimated that sustainable use of biocharring could reduce the global net emissions of carbon dioxide (CO 2), methane, and nitrous oxide by up to 1.8 Pg CO 2-C equivalent (CO 2-Ce) per year (12% of current anthropogenic CO 2-Ce emissions; 1 Pg=1 Gt), and total net emissions over the course of the next century by 130 Pg CO 2-Ce, without endangering food security, habitat, or soil conservation. It feels like every other week I read about one approach which has the potential to save us from climate change, if scaled correctly. Suberin rich food crops. Autonomous ships that produce artificial clouds. Biochar. Painting things white. Olivine rock weathering. Greening the Sahara. I don't believe any of these solutions alone is going to save the planet, but surely doing several in concert would help
astazangasta 8y ago
The efficiency doesnt matter - solar inputs are ubiquitous and require no effort on our part.
- 205guy 8y ago
  This. Anything else requires energy input (and thus carbon emissions in the current situation), whereas plants are carbon-negative from the get-go, require no effort, and just work right now (no tech to wait for, just a few more years...). Yes, plants eventually decompose and release the carbon, but every new plant buys us 10-100-1000 years until we have to deal with that carbon. The biggest problem now is finding land to reclaim with forest and preventing existing forest from being cut down (as pointed out in other comments, the mature trees store more carbon per area than new trees). In the end, our forests are competing against our agriculture and food supply (and growing population). Just like energy efficiency (home insulation and sealing) is the low hanging fruit of energy conservation, reducing the consumption and production of low-land-efficiency foods like meat is the easiest way to reduce agricultural footprint and make more available to carbon-sequestering trees.

gizmo686 8y ago

Natural cycles are approximately carbon neutral; that is why Earth has not become an iceball yet [0]. Over the very long terms, some carbon can get sequestered, which is how we got fossil fuels in the first place. But consider how long it took nature to sequester all of that carbon. Now that we have reintroduced it into the system, there is no natural mechanism to just take it back out again. We could change the steady state slightly by increasing biomass; but that would only offset the carbon added by the destruction of said biomass, and cannot scale beyond the available space (and all other natural limitations on how much life can be put in one spot). If we did come up with a way for Earth to just "soak it back up again" that was based on seeding some type of organic and letting it work for us, I would be extremly concerned about a global cooling catastrophe. There is no natural stop point at the carbon concentrations we want, and if we overshoot the amount we pull out, we are in for a very bad time. (Not to mention the other environmental effects that the resource sink we introduce will have. I doubt carbon would be the only resource it hogs.) [0] It did come close with the emergence of photosynthesis. At the time, photosynthesis was decidedly not carbon neutral, as there was no counter force to consume oxygen until the emergence of aerobic organisms. https://en.wikipedia.org/wiki/Great_Oxygenation_Event https://en.wikipedia.org/wiki/Great_Oxygenation_Event

astazangasta 8y ago
Much of our carbon contribution comes from deforestation, soil erosion, etc. In other words, habitat loss and conversion. For example, there used to be forestation across much of the "Fertile Crescent" before we had our way. Manhattan was a thousand year growth forest before Europeans showed up. Removing the dead hand of man from the scale can do much to reverse this process; actively fostering reforestation (see: Dune) can do more. We are over budget here - putting 1000 gigatons of C back is going to be tough. But putting a good chunk of that away is probably the result of something like: humanity stops eating meat and reduces its agricultural footprint, commits most of the earth to nature preserves.
- 205guy 8y ago
  I wonder why you're being downvoted, maybe people don't want to face the consequences of their actions. Though I think we don't need to be so absolute in terms of "stops eating meat," that's hard for people to handle. It would be easier to convince people and still extremely effective to reducing meat consumption to once a week and on holidays, like in the old days.

remarkEon 8y ago

>The best strategy for reversing carbon emissions is letting the Earth soak it back up again. Not really sure what you're referring to, if we're being practical. The only proposal I've seen that uses your strategy is seeding the oceans with iron oxide to cause algae blooms. I don't really know if that's truly feasible (or desirable) but it is the only one I've heard that is an honest attempt at Geo-engineering our way out of this mess.

roryisok 8y ago
Didn't someone try this in Canada with disastrous results?
- ben_w 8y ago
  It’s been tried repeatedly. Iron isn’t the only limit on algal blooms, though it is often the most relevant. I think the main problem is control over which species bloom, partly to avoid toxic bloims near fishing areas, but also as you want something that sinks the carbon rather than floating it.

agumonkey 8y ago

pardon the moonshot.. solar powered drone aggregating CO2 in the atmosphere ?