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Spreading rock dust on farms as a climate solution

200 points17 hoursanthropocenemagazine.org
spenrose16 hours ago

Paper from researchers: https://www.nature.com/articles/s43247-022-00436-3

"Using life-cycle assessment modelling of potential supply chain impacts for twelve nations undertaking Enhanced Rock Weathering deployment to deliver up to net 2 Gt CO2 yr−1 CDR, we find that rock grinding rather than mining exerts the dominant influence on environmental impacts. This finding holds under both a business-as-usual and clean energy mix scenario to 2050 but transitioning to undertaking Enhanced Rock Weathering in the future with low carbon energy systems improves the sustainability of the Enhanced Rock Weathering supply chain. We find that Enhanced Rock Weathering is competitive with other large-scale Carbon Dioxide Removal strategies in terms of energy and water demands."

MrDunham3 hours ago

I found these parts also interesting from that study:

"...it is competitive in terms of sustainability. It has half the energy demand of DACS, avoids land-use competition of other land-based technologies (Bioenergy with Carbon Capture and Storage, afforestation/reforestation/biochar), and has a 10–100-fold lower water demand than these other CDR strategies."

credit_guy15 hours ago

> by 2050, it could be removing up to 30 million tons of CO2 from the atmosphere each year, capturing almost half—45%—of the emissions the UK needs to vanquish from its atmosphere.

The UK emits about 450 million tons of CO2. They are off by a factor of 6.75

https://en.m.wikipedia.org/wiki/Greenhouse_gas_emissions_by_...

peyton15 hours ago

It’s about half of the UK govt’s target for engineered removals. Page 189: https://assets.publishing.service.gov.uk/government/uploads/...

rob749 hours ago

...so the author of the article either missed that or is intentionally misleading us - because the article definitely gives the impression that it's half the total reduction:

> A new study estimates that the low-tech method could capture almost half the carbon the UK needs to meet its climate goals

> [...]could capture 45% percent of the carbon dioxide required to help the UK meet its 2050 net-zero targets

nulbyte4 hours ago

I'm not sure what you mean by total reduction. The reduction hasnt happened yet, so the total is unknown. But we do know what is needed, and the part you quoted seems to clearly measure the proposal in terms of what is needed, not what is presently output.

webkike12 hours ago

Yeah, so, off by a factor of 6.75

eyko6 hours ago

"By 2050, deployment of engineered removals at large scale, between 75 and 81 MtCO2 per year"

Looks legit?

throwawayboise15 hours ago

You're assuming that the goal is getting to zero CO2 emission? There is no reality where that is possible.

Edit: I hadn't read the article. That indeed seems to be the goal. On that basis, yes the math appears wrong.

thfuran15 hours ago

Frankly, we probably ought to hit net negative for some while to actually unwind the mess rather than settling for merely stopping accelerating the worsening but I agree with your assessment of the odds.

BurningFrog1 hour ago

You're right that this would have benefits.

But the (very high) costs also must be considered.

In the end, I'm sure Earth's CO₂ levels will be engineered, and reverting to the preindustrial levels is not at all certain to be considered optimal.

BiteCode_dev7 hours ago

According to Jean-Marc Jancovici (https://www.youtube.com/watch?v=IaQ-U-dP_7M, in french though), this is right on the money: CO2 being extremly stable and given the quantity we already have transfered in the atmosphere, a 1.5°C global rise in temperature is inevitable already. We'd have to in the negative indeed to have a impact, and with the system inertia and the cascading effects, it's not even sure it would reverse the trend completly.

abraae11 hours ago

Agree, and yet (assuming we reach that happy place) what happens next? Who decides how high to wind the global thermostat? Would countries who have benefited from increased temperatures (Russia perhaps) all fall in line and happily agree to go back to (say) pre-industrial revolution levels of CO2?

lozenge6 hours ago

Isn't that the same issue as currently?

Every country that extracts fossil fuels is deciding to turn up the global thermostat, but rather than calling it out as a decision, we treat it as a default or an irrelevant consequence.

ido10 hours ago

Even once (if) we get to negative co2 it will take centuries for the temperatures to drop back to pre-industrial levels. We’re still taking “only” slowing down temperature increase for well beyond the lifetime of anyone alive today.

kuhewa10 hours ago

I'm not sure we need to worry about that until we are magically able to sustain negative or net zero emissions globally. On the present horizon at least it looks like we will be settling for somewhere around two degrees above from pre-industrial temperatures.

steve7613 hours ago
epgui14 hours ago

It's difficult to think of any other reasonable goal that is not at least as "ambitious" as that one. That is, if one considers "trying to survive" an "ambitious" goal.

stormbrew8 hours ago

I mean, there’s always at least one reality where this happens: the one where climate disasters escalate to the point where human civilization is no longer able to extract new carbon to put into the atmosphere.

The goal is to find a different reality than that one.

whimsicalism3 hours ago

sure, except for the fact that positive feedback & runaway warming exist and are likely.

Thorrez13 hours ago

What do you mean by "zero CO2 emissions"? Do you mean literally emitting nothing, or do you mean offstting emissions with capture, making it net zero?

stormbrew8 hours ago

Carbon zero would probably mean not putting any new carbon into the cycle. Not all carbon emissions are positive contributions to net carbon, if they’re just reusing carbon that was already being cycled through.

Consider as a thought experiment a world where we suddenly have limitless but “clean” power (ie. fusion comes sooner and better than even the most optimistic expectations) and we start doing carbon capture that also produces burnable hydrocarbons as a byproduct. Running an ICE off that fuel doesn’t put any new carbon into the air, it just recycles what was already there. Obviously this isn’t likely, but it illustrates the premise in an exaggerated way.

More practically, in theory wood from farmed, new growth trees fits this mold, but in practice it’s not a terribly efficient or clean fuel once you take all the externalities out. And obviously you’re not gonna power a car on it.

But fundamentally, the main thing we need to do to get to zero is stop breaking the planet’s own sequestration of all the carbon that was in the atmosphere before it was hospitable to modern life. At this point doing that is very much a political problem, we probably have the tech to replace the energy we’d lose from that, we just aren’t willing to build it out fast enough.

barry-cotter15 hours ago

> You're assuming that the goal is getting to zero CO2 emission? There is no reality where that is possible.

If this works then doing it more is clearly possible. Maybe not politically or economically viable in the current circumstances but certainly possible. If weathering fine gravel/dust is the mechanism there’s an awful lot of coastal land with relatively active currents in the UK and elsewhere to dump it.

throwaway0x7E69 hours ago
eastbound8 hours ago

All those CO2 calculations are done by taking what nature can absorb (3Gteq), assuming we can emit that much and dividing by the population on Earth.

- (1) As if an African person could emit exactly as much as a UK person.

- (2) As if countries who chose to overpopulate were allowed strictly proportionately to their population.

Since emissions are tightly coupled with consumption, (1) means everyone on Earth should be able to consume the exact same quantity of goods and every country would have exactly the same richness. Which is communism in the purest sense. Which, when you know a few globalwarmists, is exactly in line with their aspirations. I mean they just wanted to impose communism but they came back under a new form.

(2) Since emission calculus are proportional to population, it incentives to overpopulate to be allowed more emissions. Which, you may say, is a side-effect incentive of this calculus and is at odds with global warming. They don’t see a problem with that. Everyone should be allowed to live, they say. Again in line with communist ideals.

I’ll add (3): Every time they ask me to consume 5% less electricity, they allow 5% more migrants in the territory, then they fight to allow them to consume as much as middle classes here. So this whole story of global warming is just about this:

Stuffing more people on a territory and making everyone only able to consume exactly the same. Which, if the managers of the top CEOs of positive energy startups were your classmates (I know a bunch of them) totally aligns with their worldview when they were students (sons of hippies born with a computer and, as you say, metrosexuals with former communist ideals, generally with anti-colonial stances). I’m flummoxed that their worldview is so trendy that they succeeded in life despite major ideological flaws in their reasoning, and one of my friends is even worth 60m€.

Global alarmism is just the new form of communism, just as toxic, just as idealistic.

grapescheesee3 hours ago

Its the voice in the room, that wants to ask. Maybe we have a population issue?

No one wants to be the voice, its a political nuke.

serenitylater7 hours ago
faleidel16 hours ago
xingyzt14 hours ago

Newer studies have put doubt to olivine's effectiveness: https://www.technologyreview.com/2022/03/30/1048434/why-usin...

pfdietz5 hours ago

That was about putting olivine in seawater, not spreading it on soil.

My concern with all these approaches is the nickel content of olivine, which can be several tenths of a percent.

bradrn15 hours ago

This is pretty much exactly the same idea: the paper referenced by the article mentions basalt specifically, which has olivine as a major constituent.

heavyset_go14 hours ago

Here's a study that found that the olivine hypothesis might not work as expected: https://www.technologyreview.com/2022/03/30/1048434/why-usin...

travisporter15 hours ago

Discussed by the late David mackay. http://www.withouthotair.com/c31/page_246.shtml

eru12 hours ago

I really liked his book! I didn't know he died. That's such a shame.

csnover12 hours ago

Previous discussions on this approach:

Spreading rock dust on fields could remove vast amounts of CO2 from air (2020; 109 comments) - https://news.ycombinator.com/item?id=23770718

Potential large-scale CO2 removal via enhanced rock weathering with croplands (2020; 90 comments) - https://news.ycombinator.com/item?id=23831411

gomijacogeo8 hours ago

1. How much additional energy does it take to pulverize the rock? 2. What about the effect the rock will have on soil pH? 3. What about leached salts and heavy metals?

pfdietz5 hours ago

Pulverizing rock requires little energy, if I recall correctly. This shouldn't be too surprising as one is breaking only a small fraction of the chemical bonds in the material.

datavirtue3 hours ago

Pulverizing rock is one of the most energy intensive activities on the planet.

Supermancho25 minutes ago

> Pulverizing rock is one of the most energy intensive activities on the planet.

That's a flat statement that should be easy to look up instead of being snide, right?

Maybe you are looking to cite the Kuznetsov Equation

https://cablescalculations.wordpress.com/2018/03/23/energy-r...

https://www.reddit.com/r/theydidthemath/comments/34pvcu/requ... - this is about shattering to a size in exactly 1 swift action...which is not exactly what is being discussed. You can slowly shatter with multiple blows that take less. Imagine you're just spending energy to suspend a steel cylinder against gravity, then dropping it over and over.

kmbfjr39 minutes ago

The limestone crusher a few miles from my home can’t use more than 400-500 kW/hr judging by the power lines.

That is limestone, the article talks of basalt which seems would require more.

datavirtue3 hours ago

I was wondering the same thing. Mine dust? Seriously? Sounds like heavy metal poisoning to me.

greeneggs12 hours ago

The Future Forest Company spreads basalt on forestland for carbon sequestration [1].

Wren offers it as one of its carbon offsets [2]. However, it is currently the most expensive of their offset programs, per ton of carbon offset or removed, and significantly so.

[1] https://www.fastcompany.com/90642582/this-company-is-crushin...

[2] https://www.wren.co/projects/mineral-weathering-in-scotland

LarsAlereon11 hours ago

I think these mineral weathering programs may make the most sense when applied to the oceans, where they both sequester carbon and directly reduce the ocean acidification that is harming marine life. This is especially the case if wave action on beaches can reduce the amount of energy required to grind and distribute the rock. There also seems to be potential for additional capture by the iron content of the rock fertilizing the growth of phytoplankton in areas where that wouldn't be harmful to other marine life like coral. In areas with tropical coral adding Calcium both reduces acidity and helps shell building creatures.

elmolino898 hours ago

I am also leery about spreading mountains of silica dust on fields where it can be blown in the air and end up in our lungs eventually.

re phytoplankton/marine life: I guess basalt particles will sink. But if sinking is slow the top layer will get murky absorbing the light.

blenderdt9 hours ago

What about silicosis?

Rock dust doesn't sound very healthy. People and animals next to the farm will breathe it when the weather is dry.

birdyrooster9 hours ago

Seems like your question answers itself. They will not use silicate minerals in their mix of rocks.

blenderdt9 hours ago

From the paper:

"...which involves modifying soils with crushed silicate rocks, such as basalt."

jeremygaither14 hours ago

There is probably a lot of leftover rock from extracting everyday things like aluminum, as well as rare earth elements, which electronics manufacturing needs for many components. If the generation of the stones that get crushed and used for dusting is an output of other essential mining projects, that could further offset the costs associated with generating rock dust. It could also potentially reduce the shortage of these rare earth minerals, and associated electronic components, by attracting more mining operations to operate in additional countries.

jvanderbot16 hours ago

Crushing and distributing the required amount of rock seems challenging. Unless crushed rock is really produced enough by mining and is somehow really cheap to move (eg trains are coming back empty anyway)? It probably also adds another trip around the field for the combines?

Still, if it's this easy we really need to be doing this.

sriku15 hours ago

The article does point out that the folks who studied this accounted for the carbon cost of doing that in estimating the capture benefits.

ambrose214 hours ago

Yes, crushing and distributing is one of the main drawbacks. Too far from a mine and the net emissions are positive.

puchatek10 hours ago

It sounds like the potential of this technology is enormous so i would guess the distance would have to be very long before the emissions vaccine bet positive. Also there might be ways to combat that.

Our fastest carbon sequestration method that scales are forests right now and they are slow to grow and need dedicated space. So let's build those EV combines or whatever it takes to keep rock dust net negative.

legitster15 hours ago

There's an obvious path to a future where we can avoid the worst outcomes of climate change affordably using geoengineering.

But the loudest detractors of these ideas are those who feel any path free of suffering or moralizing must be wrong. You can almost never get to a debate on the merits.

version_five13 hours ago

I think you're right* It's easy to see who actually wants to address climate change, and who wants to use it as a lever to further a political agenda, by looking at support of different technological solutions, vs support for setting society and human progress back in some way as the only plausible solution.

*(although I'm fuzzy on what can be included in geoengineering - this technology looks interesting and I'm a big fan of carbon capture, I don't support e.g. putting something in the atmosphere to reflect light into space or anything "unnatural" like that. But just removing CO2 from the atmosphere seems safe).

ido13 hours ago

I think we should do everything we can (both reducing emissions and geoengineering) to fight climate change ASAP, but the problem is that a lot of very rich people (e.g. oil companies) are incentivized to not have people reduce emissions & will use the existence of technological solutions as an excuse to only do geoengineering.

We really need both, and as much of both as possible as soon as possible.

vkou11 hours ago

> use the existence of technological solutions as an excuse to only do geoengineering.

Actually, they use the potential existence of technological solutions as an excuse to do nothing. The politicians they bought and pay for aren't keen on funding geo-engineering.

And if they did, they'd do it out of general revenue, as opposed to a carbon tax.

+1
ido10 hours ago
jnsaff28 hours ago

> I don't support e.g. putting something in the atmosphere to reflect light into space or anything "unnatural" like that.

Putting gigatons of co2 to the atmosphere _is_ natural?

dpierce94 hours ago

Dismissing all concerns about geoengineering as moralizing is not reasonable. People are right to be cautious about geoengineering because our track record isn’t great, there are second-nth order effects which are hard to predict in a complex system like Earth, and there is no backup Earth or reset button. To wit, the geoengineering project of pumping tons of CO2 into the atmosphere every day hasn’t gone that well.

nemo44x3 hours ago

There’s this weird streak of purification rituals in modern leftist groups (to say nothing of rightist groups who go to church) that I find disturbing. It’s not just holding the political belief or stance. You have to somehow suffer and be part of the struggle against what I assume is the straight white male patriarchy or something.

dgan5 hours ago

> "assuming a baseline application rate of 40 t ha−1 yr−1 of basalt rock dust"

I am sorry, what? 40 tonnes of basalt dust per hectar?? What's hilarious is that when you look up basalt dust on internet, merchants sell it in bags of 2kg, "to be applied 20 grammes/sq meter", while 40t/ha is 4kg per sq meter!

osobo4 hours ago

So, I did exactly that and got a recommendation of up to 10lb per 100 sq feet, which is over 4kg/9sq meter, off the first hit.

datadata12 hours ago

Adding iron to the ocean to fertilize carbon sequester ING plankton is a interesting related approach: https://en.m.wikipedia.org/wiki/Iron_fertilization

mrfusion14 hours ago

So why would rocks do this but not the soil that’s already on the ground there? Isn’t it basically the same stuff?

LarsAlereon13 hours ago

The rock that's in the soil may not be the correct type, or it may have already reacted, or it may be in chunks that are too large to dissolve on human-relevant timescales. The idea is that you want ultramafic rocks, which are low in non-reactive Silica but rich in Magnesium and Iron oxides. These oxides absorb CO2 from the atmosphere to form carbonates and bicarbonates, sequestering it for geologic time. However, since reactions can only occur on the surface and when the minerals are dissolved, a big pile of mine spoil or river-sized rocks buried in the ground aren't doing much to absorb CO2. But if we grind it up into rock powder and spread it over fields, or crush it up into sand and dump it on beaches to let the ocean do much of the work of grinding and distributing it, the vastly increased surface area means a significant amount of CO2 can be absorbed in a human lifetime.

There can also be pros or cons associated with the minerals in the rocks. For example, you don't want to spread rock containing heavy metals on fields where you grow food. On the other hand, rocks rich in Potassium are a beneficial fertilizer, and Iron-bearing rock spread in the ocean can encourage the growth of phytoplankton that further absorb CO2.

baking1 hour ago

The minerals in the soil have already been weathered and absorbed as much CO2 as they can. The important thing to understand is that it is only accelerating a natural process that has kept earth's temperature relatively stable for billions of years. This is true long-term carbon capture and it is worth researching the best way to do it.

opportune13 hours ago

Soil with CO2-absorbing minerals that’s already exposed to the air would already have absorbed the CO2. It’s like saying why plant trees to remove carbon from the atmosphere when we already have trees.

pfdietz5 hours ago

Olivine is a particularly easily weather silicate, because the silicon atoms are in isolated SiO4(-4) tetrahedra. In most other silicates, the silica tetraheda are linked covalently by shared oxygen atoms and weather much more slowly.

barry-cotter13 hours ago

The surface area of a mountain and the surface area of that mountain ground into fine gravel are very different. The same thing happens to the surface area in both cases, yes.

rascul15 hours ago

Is this meant to be spread on cropland? I figure so because they say farmland and the (stock?) photo appears to be crops but I didn't see it specifically mentioned. What affects will it have on the crops?

ggm15 hours ago

"It depends" some rock is net beneficial, can be both structural, physical-chemical effects on soil regarding clumping and water retention, and bio active (supporting beneficial micro-organisms, providing micro nutrients)

Some phosphate rich rocks might be also known as.. fertiliser.

Arsenous rocks would be a disaster. It's a huge issue in India with water table and ground contamination. Likewise lead, or salt (in the wider sense if it causes brackish ground water) although that's about deep wells. I have no idea if this is a serious risk for rockdust plans.

For enough upside benefit downsides might have to be borne or mitigated.

kuhewa9 hours ago

The type of rock dust they are talking about is already commonly used as a soil amendment to add trace elements and minerals. That said it is possible I suppose that the optimal amount for carbon drawdown is greater than the optimal amount for crop health or yields

rascul12 hours ago

Basalt is mentioned in the article. I know just a little bit about farming and growing things but I don't know anything about this rock stuff. But if it's good (or, perhaps, at least not bad) for the crops then it does seem like a possible good idea.

kuhewa9 hours ago

Basalt rock dust is a pretty common amendment to add trace elements to soils especially in organic gardening

ncmncm14 hours ago

Clearly if you are putting it on farmland, the farmer will demand the beneficial stuff and reject the harmful stuff.

There are lots of opportunities for harm, but plenty of material that would be beneficial, particularly for crops that like higher pH.

Olivine, e g., often has excess nickel, which you then would not use on farmland. You might dump that on beaches, instead. The main thing is to move a lot of it. You would prefer to use renewable electric to crush it, but the main thing is to get started.

abraae14 hours ago

Where I live, beaches are virtually sacred and certainly not the places to dump anything.

ncmncm12 hours ago

Olivine makes them a pretty, glassy green. But anyway you would put it on the many, many thousands of miles of shoreline where people are not, to be stirred by wave action.

kuhewa9 hours ago

If you lived near South Point, Hawai'i Island, you'd already have a (natural) olivine beach.

colechristensen14 hours ago

A normal soil ecosystem has fungi breaking down rocks to gather nutrients and sometimes exchange with plants. It could be a sort of fertilizer but certainly there would be a point of over applying which would have to be understood.

tekstar14 hours ago

Probably a sort of crunchy effect, but hey it's high in minerals

eru12 hours ago

Compare Gwern's proposal: https://www.gwern.net/CO2-Coin

penneyd16 hours ago

Any obvious downsides to this approach?

ambrose214 hours ago

Mining the rocks, distributing the rocks to a central processing center, then shipping to the farms is all non-negligible and can easily be net positive emissions rather than sequestration.

Thorrez13 hours ago

It looks like they've considered that:

>Their model also incorporated the emissions costs of mining and then spreading this powdered rock over fields.

Of course, there's always a chance of errors in both how they estimated these emissions and how they estimated the amount of CO2 that will be removed.

ambrose22 hours ago

> Transportation. Detailed transport analyses (based on UK road and rail networks) were undertaken to calculate distance costs and CO2 emissions for the distribution of rock dust from source areas to croplands. We used the GLiM database for the UK distribution of basalt deposits and the 2019 land cover map (Supplementary Information) to calculate transportation distances, cost (£ t−1 rock dust km−1) and emissions (tCO2 km−1) from potential local rock sources to cropland areas, together with UK road and rail transport networks. Spatial analysis was undertaken with least-cost path algorithms from the ArcGIS software.

Yea, it sounds like the model took this into the account, maybe the assumption that rock sourcing could rely on mines within the UK. If so, given the size of the UK, if the majority of transportation is by train and EV over UK distances, this might not be an issue.

sriku15 hours ago

Might need to be studied in different regions to determine whether there are any detrimental effects. It looks like it might alter the soil pH which could affect crops.

Sounds promising though.

pfdietz5 hours ago

Nickel pollution.

eru12 hours ago

It costs a lot of money.

ffhhj15 hours ago

Do rock minerals capture more oxigen than carbon?

ncmncm14 hours ago

They are mostly already oxidized.

eru12 hours ago

And it wouldn't matter too much (within reason): we have vastly more O2 in the atmosphere than CO2 we want to get rid of.

ncmncm9 hours ago

The CO2 is at <0.05% concentration. O2 is at >21%.

Maursault15 hours ago

Also, inevitably running out of rocks.

brokencode15 hours ago

Can somebody who knows about rocks weigh in here? I was under the assumption that pretty much the whole Earth crust was made of rocks, and that we’d run out of virtually any resource before we run out of rocks.

unlikelymordant14 hours ago

Basalt is extremely common, its not something that anyone will run out of.

We may run out of basalt sources that are close enough to farmland it can be spread on, but it would take a while. And trains would change the economics.

furins11 hours ago

All the oceanic crust is made of basalt, so approximately 2/3 of the planet is covered by several miles of it. Unfortunately mining oceanic crust is impractical, for obvious reasons. However some oceanic crust got trapped between mountain ranges during continental collision, forming ophiolites. These can be suitable mining sites, together with LIPs (large igneous provinces) and the rocks of some shoshonitic (K-rich) basalt volcanoes.

heavyset_go14 hours ago

I'd imagine the types of rocks would matter. There are also a lot of ores that should remain in the ground, and not pulverized and spread, contaminating water and soil.

eloff15 hours ago

Rock is not a scarce resource. The planet is literally made of it.

WalterBright13 hours ago

We're all just pond scum on a ball of molten iron.

verisimi4 hours ago

> The simple act of sprinkling rock dust—an abundant byproduct of mining—on farmland could capture 45% percent of the carbon dioxide required to help the UK meet its 2050 net-zero targets.

Has this news been brought to me via the 'mining board'? Is it an attempt to get us to pay for their waste?!

And won't rock dust degrade the soil quality?

gonzo413 hours ago

Depending on the size, it would be like putting a sand through the soil. Great for drainage.

lifeplusplus7 hours ago

What happens after multiple layering / years after, won't you at some point remove rock layer to keep fertile soil

daodedickinson10 hours ago

I have rocks to sell if anyone's buying.

ck214 hours ago

Is "rock dust" proven, peer-reviewed and reproduced or is it some pet-theory of an academic or two?

Because one thing I've noticed especially over the past two years of covid research, once some PhD seems to vapor-lock onto a single substance as a "miracle cure" they can write endlessly, breathlessly about it without mentioning a single downside or limitation.

black_132 hours ago
paulcole14 hours ago

Whatever it takes so that nobody in America has to make any substantive changes in their way of life.

moron4hire2 hours ago

Article is about the UK, but regardless, if it can be done, why not? You got some kind of neocatholic guilt going on? "Climate change mitigation doesn't matter if it doesn't come with a heaping side of suffering".

snidane13 hours ago

If the rock dust captures so much CO2, what will the plants breathe?

Thorrez13 hours ago

I think the idea is to get the CO2 levels to what they were 200 years ago. Plants breathed fine back then.

snidane1 hour ago

Why 200 years, an not say few million years? Used to be more CO2 and plants liked it better. Definitely grew higher back in those days.

I suspect the answer 200 because it is assumed these days that CO2 produced since 1800 is all man made. Would like to genuinely know if that's the case or I'm missing something.

hosh11 hours ago

Isn’t that adding more dead dirt to dead dirt, rather than cultivating soil? How does rock dust encourage soil bacteria and fungi that symbiotically trade minerals for sugars with the plants?

It might be low-tech, but it’s not really a regenerative approach.

mjsweet11 hours ago

I am a worm farmer and soil amendments manufacturer. One of the most important ingredients that I feed my worms is blue metal and zeolite rock dust. Trace minerals including elements like boron and sulphur are important for cellular growth. The Australian continent where I am has extremely weathered soil, depleted of minerals. I hope to help put minerals and biology back into the soil.

wokwokwok14 hours ago

It's hard not to be skeptical.

If only there was a way to solve climate change with carbon capture that was low tech, easy to do, simple to understand, didn't pose any long term side effects and pretty cheap to do.

Oh, and it can solve all the CO2 emissions you could ever want, so you know, you don't even have to make significant changes to your industry or way of life, because your emissions are pretty much flat out neutralized by this one simple thing.

Sounds perfect right?

Sounds like a silver bullet.

...but, silver bullets don't exist.

So, I can guarantee it's not that simple. Maybe it's another useful tool to help tackle climate change, probably with more research as to how to actually works. ...but, I think anyone who's excited by this needs to calllllmmm the F down, because this idea has been around for quite a while, and no one is using it; so I suspect there are some things that still need to be figured out like:

- do the benefits scale linearly, or is it a logarithmic curve (like most things)?

- can you actually measure the amount of carbon captured to prove its working?

- does it have any side effects on the ecosystem?

- does it have any impact on, you know, the farms you're putting it on?

- does their model (which is all they did, create a Matlab model) actually work in the real world?

- how often do you have to do it for it to stay effective?

It's complicated right.

I mean, sounds promising... but this:

> The simple act of sprinkling rock dust—an abundant byproduct of mining—on farmland could capture 45% percent of the carbon dioxide required to help the UK meet its 2050 net-zero targets.

Is just idle wishing the problem away. It might. It might not. There's a model that suggests it might.

I'm not convinced we should be sprinkling rock dust over the entire country quite yet.

WalterBright13 hours ago

> carbon capture that was low tech, easy to do, simple to understand, didn't pose any long term side effects and pretty cheap to do.

Plant a tree.

DoreenMichele13 hours ago

Pshaw. Plant lots of trees.

Even poorly educated, dirt poor people in underdeveloped countries can do it. (And are. See for example Pakistan, where they are planting 10 billion of them.)

furins10 hours ago

- does it have any side effects on the ecosystem?

- does it have any impact on, you know, the farms you're putting it on?

These two questions probably already have an answer: we already grow plants, vegetables, fruit trees on basaltic soils (soils formed by the erosion of basaltic rocks). Some European countries have almost only them, like Iceland, Albania, Montenegro. Usually the crops are excellent, and benefits directly from this natural fertilizer e.g. some Italian wines. These rocks also help to capture water in arid regions, btw. We are also plenty of real world experiments of adding these substances to other ecosystems: every basaltic volcanic eruption distribute a dust cloud around the vent, usually in an area of hundreds km^2, influencing the environment.

barry-cotter13 hours ago

> Sounds like a silver bullet. ...but, silver bullets don't exist.

There are many, many examples of miracle technologies that have huge effects for the resources expended on them: antibiotics, vaccines, printing, writing, mathematics, the transistor.

wokwokwok13 hours ago

"Put extra dirt on your fields" isn't really in the same class as those is it?

eru12 hours ago

How do you define classes?

For something that sounds similar:

When people didn't understand soil and biology very well, fields needed long fallow periods to recover from growing wheat and other crops.

As part of the British Agricultural Revolution, they figured out that they could plant turnips and clover instead:

> One important change in farming methods was the move in crop rotation to turnips and clover in place of fallow. Turnips can be grown in winter and are deep-rooted, allowing them to gather minerals unavailable to shallow-rooted crops. Clover fixes nitrogen from the atmosphere into a form of fertiliser. This permitted the intensive arable cultivation of light soils on enclosed farms and provided fodder to support increased livestock numbers whose manure added further to soil fertility.

https://en.wikipedia.org/wiki/British_Agricultural_Revolutio...

barry-cotter12 hours ago

Putting the right kind of extra dirt is in the same class. Fertilizer can increase yields by 20% or more. That’s a magic bullet. Technology is nothing but the quest for magic bullets.

wokwokwok10 hours ago

It’s not.

There are no magic bullets.

Every action has consequences; as you see from the effects of using fertilisers and pesticides.

“Perfect fixes” with technology don't happen. Perfect fixes have no side effects. That’s incredibly difficult to achieve in complex systems.

Whether you want to believe it or not, doesn’t change the facts.

Breakthrough transformative technologies do exist, but those simply change things they don’t magically fix them.

What you’re espousing is not “truth”; it’s simply a philosophy, considered by many to be a short sighted trivialisation of a complex problem. See -> https://en.m.wikipedia.org/wiki/Technological_fix