I am a climate scientist, and it isn’t very often that I feel like I get to share good news with people. Luckily, every so often good things actually do happen. I have said on this site a few times before that climate science is relatively young as a field of study, and though things may feel bad at times, some of the best scientists in the world are working in the background to address our major climate issues.
Four years ago right here on Hexbear I was addressing some comrades’ concerns about climate in the long term. I told them that of course the situation we are in really is terrible, but there is one method in particular that has some real potential to majorly address our climate crisis: Silicate weathering. This method has been one of the primary methods of carbon cycle management throughout earth’s history, albeit over time periods of millions of years, and all we have to do is figure out how to apply it to human timescales. Just as I predicted, that is still indeed the most promising method of carbon sequestration, and it just took a giant leap towards viability, as outlined by the study I will be talking about with you today.
(My commentary from 4 years ago if you don’t feel like following the link)
On the, “What can be done?” side, luckily you have some of the smartest and most dedicated scientists in the world working on ways to sequester carbon, and the most promising method is accelerating the silicate weathering process which is the most effective tool to combat man made climate change.
For those who don’t want to read or don’t understand, I’ll briefly summarize why this method is important and the most likely candidate:
You may be thinking “oh let’s plant trees” which is good, sure, but consider that we are re-adding carbon which was not actively in the carbon cycle back into it. A mature forest is most times carbon neutral, as carbon output from decaying biological matter is roughly equal to carbon uptake (think about the following: how could forests continue to exist in the first place if they sucked out more carbon from the air than was added to it?)
Now think where we are getting our carbon that we add back to the atmosphere from. We pull it from underground deposits. The beauty of silicate weathering is that it incorporates carbon into rocks, and thus acts as a long term storage vessel when removing carbon from the atmosphere. The big problem though is that this process happens naturally over the course of tens of millions of years as a result of plate tectonics uplifting mountain ranges and these ranges getting weathered (as implied by the name “silicate weathering”).
So now geologists and climatologists are trying to figure out ways to massively accelerate that process, which has only become a remote possibility over the last 15 years.
How it works:
What it means in less scientific terms:
Enhanced rock weathering (ERW) in farmland is a method to sequester atmospheric carbon on medium-long term timescales. This study measured this carbon sequestration process as a way of potentially increasing crop yields while simultaneously removing carbon from the atmosphere through the silicate weathering process. Testing this process demonstrated ann improved crop yield of 8%-18% in humid regions, plus improvements in overall soil quality. Soils with higher alkalinity sequestered the most carbon, especially in high precipitation scenarios. Expanding this study to all viable farmland across China has the potential to sequester .4gt of carbon yearly, or roughly 3% of China’s yearly CO2 emissions. Economically, utilizing this method is comparable to the cost of heavy soil modification already used for intensive agriculture. The use of ERW in nutrient poor/overly acidic soils provided a comparable effect to common agricultural practices of using lime and fertilizer to decrease acidity and raise nutrient levels. Additionally, the silicates needed to conduct this process are commonly found in waste products of advanced manufacturing and industrial processes, which could mitigate the carbon impact of manufacturing, industrial, and farming sectors while also lowering expenses in each.
Utilizing this method globally, we have the ability to improve the quality of our farmland while also removing carbon from the atmosphere at relatively fast rates, all things considered. Of course, we will still need to go carbon neutral in terms of energy production, but once that is achieved we have an actual method to remedy some of the harm we have already done to earth’s climate. Our long term climate solutions, should we use this method, are possible on a scale of decades-hundreds of years (and that’s with only our currently available technology!) as opposed to the thousands of years or longer we previously thought.
xi jinping commits GENOCIDE against hunger, adds carbon dioxide to his LIST OF VICTIMS
Death to America
And then those same western nations who refuse to fund their sciences get all pissy and throw temper tantrum/enhance McCarthyism when those labs lacking funding collaborate with Chinese research groups.
It's a little surreal seeing silicate weathering as a short term climate solution. Goes against what I learned in my undergrad classes lol.
Pretty much every country does farming subsidies anyway, so it would be straightforward to implement. Cool stuff.Taking a geochemical process that normally occurs on a tens of millions of years scale and turning it into an industrialized process to manage our climate would be quite the achievement.
But if humanity is remembered for anything in our planet’s hall of records, it'll be for changing earth’s climate rapidly
(Intentional) geoengineering is only going to get more popular. Gonna be a weird century, that's for sure
Really cool! So pleased to see at least China doing progress on this. Albeit marginally, my climate despair is reduced and my climate-fix determination is increased.
Question - How does rock dust improve crop yield? Isn't carbon and mineral like the one thing the soil is already full of? I thought nitrogen / phosphorus were typically the limiting factors in soil nutrients.
Here’s the real motivation:
We have known for a long time that going carbon neutral alone is not enough anymore. We need to sequester carbon long term, just like it was before we used it. Now the science to do so is here on a scale that could remedy our cumulative climate impact within the foreseeable future IF AND ONLY IF we can get global emissions as close to zero as possible.
To answer your question, instead of adding chemical fertilizers, the “rock dust” you are adding undergoes a chemical process where it binds with atmospheric carbon, which increases the amount of inorganic carbon in the soil. This inorganic carbon facilitates mineralization (decay, oxidation) of organic material within the soil. This decay takes the organic chemicals which would otherwise be locked away in organic matter (complex molecules that contain all of the things in plant fertilizers) and turns them into usable chemical nutrients for plant life.
If one simply wanted to maximize the amount of carbon removed from the atmosphere and ignored the agricultural aspect, would it also be possible to just have a conveyor belt carrying freshly ground rock dust with a fan blowing at it? Alternatively, if the process is too slow for that, a warehouse full of densely packed shelves, each coated in dust, with outside air being moved through it? Or does it rely on some other substance in the dirt? I'm pondering ways this could be scaled up purely for carbon-capture purposes.
Isn't carbon and mineral like the one thing the soil is already full of?
Supplying crop nutrition and weathering are parallel processes. Plants naturally acidify soil as part of the process of absorbing nutrients, and those acids are typically neutralized by binding with unweathered minerals in the soil. This process enables the release of beneficial mineral nutrients such as calcium and magnesium for plant uptake while also mineralizing carbon. Over time and intensively worked agricultural soils, these nutrients deplete, and most agricultural soils are now at least a little deficient in these minerals. Basalt dust can help reverse the process.
This is indeed extremely promising. Enhanced weathering is one of the few geoengineering (broadly construed) approaches with some potential. The big problem, as you alluded to, is the production and distribution chain. I haven't read the study yet, but most global-scale approaches to this would require and an extraction and distribution industry similar in size and intensity to the fossil fuel industry. Not only is that challenging to spin up overnight, but it's again hard to do in a way that isn't itself so carbon intensive that it wipes out most of the gains. If our leaders weren't cowards, they'd nationalize all fossil fuel industry companies and tell them "you're extracting and distributing this stuff now," but alas.
Yes, exactly. And we are talking about just using it in farming applications here. What makes this research promising in particular is that it is comparable in cost to intensive agricultural practices for similar results in production. A simple government subsidy could make this an extremely effective climate friendly change where the process is viable.
But like you said, that is frankly only 1/3 of the story. Another piece of the problem is that even if it immediately became cost effective on farmland globally, the mineral extraction process would have to be carbon neutral (or very close to it) to actually begin the process of net carbon removal from the atmosphere.
And the last piece is that even assuming full carbon neutrality in extraction and energy production globally, the rate of carbon sequestration via global agricultural ERW only would not be fast enough to meet humanity’s needs before we start to see some of the worst, baked in impacts of climate change from our cumulative carbon output. While carbon sequestration with profitability in the agricultural sector is nice, we would need to industrialize this process beyond just agriculture, for the sake of carbon sequestration itself.
Which of course brings us to the fact that the future is indeed going to be socialism or barbarism. There is no future in which just sucking up carbon, an inherently unprofitable venture, can exist under capitalism. A socioeconomic order where the wellbeing of humanity is of the highest importance is absolutely necessary to make something like this actually possible.
before we start to see some of the worst, baked in impacts of climate change from our cumulative carbon output
Is this actually true though, or an artifact of our limiting modelling horizon.
Intuitively it seems hard to believe that 2100 would be worse than say, 2500 once all the ice caps and glaciers have completely melted and tilted the albedo further to a hot house jungle.
I'm not sure I understand the question. The claim isn't that 2100 is going to be worse than 2500, but rather just that a certain amount of warming is already "in the pipeline" because the Earth's energy balance hasn't equilibrated to the GHGs already in the atmosphere. Even if we went carbon negative today, we'd still experience some amount of warming unless the removal rate was so high that it could bring the CO2 levels down on a time scale that's smaller than the "catch up" time for the baked-in warming we've already got coming (which is on the order of decades).
This is part of why people don't take carbon capture and sequestration by itself seriously as a solution: unless we can effectively run the whole fossil fuel industrial complex in reverse--removing and sequestering CO2 at the same rate we're now emitting it--even a negative emission rate at this point isn't going to be enough to dodge the serious warming we have coming. And the technology to go that negative that quickly simply does not exist, nor is it even close to existing. This plan is better (and by a fair margin) than anything else suggested so far, but it still doesn't get us anywhere near "silver bullet" territory.
My question was whether this was valid:
the rate of carbon sequestration via global agricultural ERW only would not be fast enough... before we start to see some of the worst [impacts]
Which I don't think it is - the rate of carbon sequestration via ERW is insufficient to mitigate severe climate change impacts in 2100, but any level of net CO2 atmospheric removal is good because the very long term impacts of climate change are progressively worse.
This is also a rebuttal of the potential doomerism that because we can't avert climate impacts over the next century, it's not a solution at all [and therefore we shouldn't bother]
Is this basically adding rock dust to your field?
I basically learned about it from some organic weed growers back in the day
Yes that is basically it, but on a global scale to combat climate change it’s a bit more complex.
Yeah I assumed it was a tiny bit more complex than that, I just think it’s cool that some weird hippies growing organic weed put me on to this tech like 8 years ago and that it actually works
Lol well the chemical processes themselves are not brand new scientific discoveries! Increasing the amount of inorganic carbon in the soil can be a huge boon to farming, especially those who are trying to farm without added chemical fertilizers.
This idea has been around. I remember a US based startup was looking into this, and having trouble securing funding lmao.
Yeah the actual chemical process is nothing new, neither is its known impact on global climate. The biggest problem has been the barrier to research, because only after the research is done can anybody start looking in to funding projects at scale like this one.
The fact that this study can be considered a pretty big breakthrough while simultaneously being something all climate scientists, chemists, geochemists, geologists, and those in the agricultural research have known to be possible for a long time is genuinely sad.
This is making me cry. Thank you. It’s been a rough couple of weeks with the weather in my city and I just keep feeling hopelessness in waves.
It really means a lot that you care so much. There’s obviously a ton of work to be done, mostly on the transition to green energy. We absolutely have the means to have net zero carbon energy production within our lifetimes, it’s just about making sure that becomes reality.
That has always been only one piece of the puzzle though. We need to actively remove CO2 from the atmosphere to actually halt or reverse climate change, which is why this process is so important.
Is there any way to do small silicate production? Could I collect rocks and break them into dust on weekends? Or does it have to be specific types of rocks?
I wouldn’t advise doing that. It would be a lot of work for very little reward, plus a major health risk depending on the rock/minerals you are breaking down. In theory though yes that is possible
I remember that post and think about it regularly. It’s the one thing that’s given me hope that we as a species can actually unfuck the climate situation we’ve put ourselves in.
Nothing makes effortposting worth it more than hearing things like this.
Not to be a wet blanket but the "Will it scale?" question applies as much here as it does with any other CO2 mitigation strategy. The paper's application rate was 100 t/ha, which is an enormous amount of material to move around. There are also limits to the amount that you can safely apply because of the presence of heavy metals.
These aren't reasons not to be enthusiastic - goodness knows working in the climate adaptation and mitigation space is a depressing grind and it's a daily struggle to not give into hopelessness and despair. Any functional solution is better than no solution at all, but I'm leery of the "silver-bullet" style reporting that enhanced silicate weathering has attracted lately.
Silicate weathering is not perfect but in terms of long term carbon sequestration there is no match.
I said elsewhere in the comments that we aren’t going to fix our climate crisis simply by farming with silicate dust (especially without a carbon neutral society) but it certainly is a great place to start. It is especially useful to help build scale for it, but also to help build the proper research base necessary to eventually begin the process of silicate weathering for the sole purpose of carbon sequestration.
Yes, ag research in general is criminally underfunded once you strip out the relentless push to grow yields of high-intensity commodity crops, and I haven't yet seen any reason not to include ESW as a mitigation strategy, but I think its capacity as a carbon sink is going to be lower than some of the more optimistic estimates given the logistics hurdles and physiological limits of the biological processes that operate on soils.
I do not see the agricultural sector being the actual solution, but a doorway for research to come to the actual solution.
A huge part of my motivation as a socialist is that we require a global society that values the longevity of our species and stability of the earth’s climate. A socialist society with these values would overcome our current issue of scalability because there really isn’t any better long term solution than the one that, in the opinion of most geologists and climate scientists (myself included), has historically be the strongest regulator of atmospheric CO2.
The problems associated with the actual industrialization of this process are ones that must be dealt with to solve the problem at hand, and some of the negative consequences will likely just have to be the price we pay for remedying our global impact on climate.
I do not see the agricultural sector being the actual solution, but a doorway for research to come to the actual solution.
The actual solution here being what exactly? The reason ESW has focused on agriculture up until now is because it's where soil weathering occurs the fastest and has some economic benefits to defray the costs of implementation. Spreading silicate dust on natural ecosystems is likely a no-go given the law of unintended consequences and the fact that sequestration rates will be significantly slower. Facilitating it using some sort of mechanical process will likely be too resource-intensive to make it worth the squeeze.
The problems associated with the actual industrialization of this process are simply ones that must be overcome, and some of the negative consequences will likely just have to be the price we pay for remedying our global impact on climate.
This isn't a "force of will" problem - the processes associated with mining gigatons of basalt to implement this solution are going to be expensive, energy hungry at a time when energy is going to come at a premium, especially in terms of highly dense, easily stored and moved liquid fuels, and require expansive infrastructure that will itself consume and compete for other resource stocks. As climate change continues, it will impose increasingly severe restraints on our ability to maintain a global supply chain and there will be discussions about the tradeoffs between spending resources on this (which will reduce impacts in the future but is unlikely to have any immediate mitigatory effect) and the more immediate and pressing needs of adaptation to the climate we currently have. Even assuming we go carbon neutral and scale this up tomorrow, we'll still have a minimum of 2 degrees of warming baked in and likely more given the increasing releases from permafrost thawing. Areas which might look like mining sacrifice zones now might be needed for farmland in the future as humanity retreats toward the poles. Writing off potential tradeoffs as a "price we'll have to pay" is a cavalier attitude that handwaves very real issues of scale and implementation and not likely to get much traction among decisionmakers focused on meeting more immediate needs.
I do not have the energy to respond to every point you are making, but I’ll respond to the idea.
First, a carbon neutral society was half of my point. To attempt this massive operation by only burning more fossil fuels would be defeating the purpose. Second, while many of the points you are making are valid, it brings us back to what I was saying. This is a problem that will need to be solved via force of will, not because I happen to think that’s the perfect way to solve it, but because that is the reality of our current situation. It’s ironic that you call what I’m doing “handwaving” while you list off the catastrophic consequences of not solving this problem as soon as possible.
We could wait until we face starvation, war, mass migration, or societal collapse because of climate change, or we could recognize the severity of the situation for what it is and take the best appropriate action as soon as possible. If we needed a perfect solution before taking climate action, we would be better off investing our resources on inventing a Time Machine to go back and stop the first coal furnace from firing.
Other than that, you are going to need a massive chemical reaction and mass amount of energy to make addressing climate change with a long term solution possible somewhere, somehow. That is what it takes to turn that atmospheric carbon, which we derived from rock and mineral deposits, back into a similar form for long term storage. There’s no other way around it.
If we zoom out, the point of contention here is whether climate change is a problem (something that has a solution) or a predicament (something that doesn't). I'm in the predicament camp because it doesn't seem like we're going to be able to pull up before we hit the wall, and so, while mitigation remains a good idea, emphasis and urgency should be on trying to minimize the consequences of global temperatures hitting (and potentially surpassing) 3 C.
I'm sensing some teleological reasoning here - you argue because we're screwed if we don't have a solution, there has to be one, and that because this is the best solution, it has to work. I'm not saying there might be a better solution, I'm saying there might be no solution. The catastrophic consequences are coming regardless of whether we implement this at scale. The paper you cited mentioned widespread application of basalt powder potentially sequestering 2 Gt of CO2 a year. That's maybe enough to cover our current agricultural emissions but it's under 1/16th of global annual emissions. Even if we do cut our carbon to 0 and still manage to implement this project (somehow under conditions of greater energy and material constraint that we have currently, given the amount of mineral resources that will be necessary to secure a green energy transition), that's a decade and a half to undo one year's worth of emissions, not counting CO2 release from other sources, like thawing permafrost, which will continue while we attempt to undo carbon that's already in the atmosphere. Force of will cannot change the math on this.
In the meantime, starvation, war, and mass migration are already happening, and the mass migration part will need a substantial amount of support of it's not going to result in tragedy. The largest mass migration of possibly any living thing in the planet's history is about to begin and we aren't prepared for it. Are we going to be able to afford ourselves the luxury of making sure the future isn't quite as hot, or are we going to be forced to prioritize the present?
So, is your point just that we're turbofucked? Is this line of reasoning productive, or is it an excuse to give up and do nothing?
I think of it like this: you're gonna die. At some point. Probably not tomorrow. Do you use that as an excuse to do nothing or do you get up and face the day?
Humanity is headed toward a catastrophe and all signs are there's little we can do to avert the fact that it's going to happen. We can continue to look for solutions, and that money is definitely better spent looking for mitigation strategies than, say, weapons R&D, but, as of today, it's peddling false hope to say that we have a way to sequester enough carbon to avoid a major disaster.
We are, however, in the privileged position to help shape what comes next. If anything, I think the techno optimistic idea that we're a breakthrough away from fixing everything contributes more to inaction than acknowledging that we're turbofucked.
The primary contributor to inaction is the profitability of inaction. It has nothing to do with what you or I think or do in our daily lives. It's unfortunate, but meetings about climate change solutions research always center around profitability and establishing markets.
Neither you nor I are in any kind of a privileged position to help shape what comes next. Even world renowned climate scientists are in no position to. The people who are are the same people who caused the climate catastrophe in the first place. You want mitigations? Well, I keep coming back to the idea that the only way for us to stop or even mitigate the effects of climate change are to
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oil executives.
Very interesting. I wonder how the “international community” will react. I’m sure they’ll receive these theories with great enthusiasm and actively collaborate with Chinese scientists to make a better world!
this might actually help tho because carbon capture gives oil companies a excuse to keep drillin.'
13 percent yield increase is nothing to shake your head at for sprinkling some silicate powder around
This is awesome, but all I'm thinking about is how UBI would just get swallowed up by landlords raising rent.
