Ocean geoengineering scheme aces its first field test(science.org)
science.org
Ocean geoengineering scheme aces its first field test
https://www.science.org/content/article/ocean-geoengineering-scheme-aces-its-first-field-test
44 comments
drill spiral tunnels in some mountains and pump water though them.
thank you for posting!
> a very negative connotation in non-scientific publications.
yes, after decades in higher ed, I too find a very negative connotation in the field of "geoengineering"
> a very negative connotation in non-scientific publications.
yes, after decades in higher ed, I too find a very negative connotation in the field of "geoengineering"
Um....is anyone working on the two methods you mentioned?
If you have any links I'd love to learn more. (And if your climate research group is involved in stuff like this, I'd love to check that out.)
If you have any links I'd love to learn more. (And if your climate research group is involved in stuff like this, I'd love to check that out.)
Vesta, Ebb Carbon, Planetary Technologies, Heimdal (YC), some stealth companies, and some academics are looking at OAE directly.
(may be missing a few)
There are a lot of terrestrial enhanced weathering folks too, where the alkalinity eventually washes into the ocean after being spread on land.
(may be missing a few)
There are a lot of terrestrial enhanced weathering folks too, where the alkalinity eventually washes into the ocean after being spread on land.
I’m really interested in learning more about ocean modifications to enhance its ability to store carbon (not via seaweed farms) or protect life that is fragile to increase acidity levels. Do you have any recommendations for further reading? Feels like everything I real on this topic is either carbon removal or solar geoengineering
This sort of thing?
https://iopscience.iop.org/article/10.1088/1748-9326/ac002d/...
... Oceans equilibriate with the atmosphere after a few months (they absorbs more co2 in response to pH/carbonate shift), so one has to keep injecting alkalinity to keep a local ecological effect. The CDR effect is persistent, though.
https://iopscience.iop.org/article/10.1088/1748-9326/ac002d/...
... Oceans equilibriate with the atmosphere after a few months (they absorbs more co2 in response to pH/carbonate shift), so one has to keep injecting alkalinity to keep a local ecological effect. The CDR effect is persistent, though.
Are you kidding me? One large mountain? That can’t be true. Why are we collectively losing our shit over climate change when we should just blow up some coastal mountains?
This seems eminently doable and a lot cheaper than just moving every city away from the coast, among other things.
I feel like there’s some fineprint I’m missing.
This seems eminently doable and a lot cheaper than just moving every city away from the coast, among other things.
I feel like there’s some fineprint I’m missing.
1) You can't just blow them up. You have to crush the rocks into something resembling sand to get the alkalinity released in human time scales.
2) Large means quite large. I ran a back-of-the-envelope estimate some years ago and found that the Hawaiian island [1] of Kauai could reduce atmospheric CO2 roughly back to pre-industrial levels if it were completely pulverized and weathered away down to the seafloor. That's trillions of tons of rock.
3) The benefits of curbing CO2 are shared globally, but the costs are concentrated locally. It's the same kind of prisoner's dilemma that results in e.g. people still burning billions of tons of coal each year.
I think that accelerated silicate weathering is the best geoengineering option and one that's likely to be deployed at scale later this century, but it's not really going to be easy.
[1] AKA "underwater mountain, with the top poking above water"
2) Large means quite large. I ran a back-of-the-envelope estimate some years ago and found that the Hawaiian island [1] of Kauai could reduce atmospheric CO2 roughly back to pre-industrial levels if it were completely pulverized and weathered away down to the seafloor. That's trillions of tons of rock.
3) The benefits of curbing CO2 are shared globally, but the costs are concentrated locally. It's the same kind of prisoner's dilemma that results in e.g. people still burning billions of tons of coal each year.
I think that accelerated silicate weathering is the best geoengineering option and one that's likely to be deployed at scale later this century, but it's not really going to be easy.
[1] AKA "underwater mountain, with the top poking above water"
For #3, I wonder if the way out of the prisoner’s dilemma would be to use this method specifically for local ocean acidity reduction. Over time it helps globally but it doesn’t do so quickly enough that other countries become disincentivized from doing the same.
I’m sold, where do I sign up? Seriously, this sounds so amazing, I’m blown away* that I’m only learning about it now!
* pun intended
* pun intended
I don’t know the details of this concept but even if it’s true we have to decarbonize our economy or we’ll just have to keep blowing up mountains. Also I presume the parent meant “one mountains worth of lime” and I presume most mountains aren’t pure lime.
We will decarbonize. The only fossil fuel we have in massive abundance is coal, and it’s already not economical for electricity generation. Natural market forces could get us there alone. The problem has always been that it doesn’t get us there fast enough.
If we can just mine a mountain worth of lime and dump it in the ocean, that seems simpler and cheaper than trying to move all our coastal cities. Even if we decarbonize at the maximum possible speed, we’ll still have to do that.
If we can just mine a mountain worth of lime and dump it in the ocean, that seems simpler and cheaper than trying to move all our coastal cities. Even if we decarbonize at the maximum possible speed, we’ll still have to do that.
What timeframe do you think every coastal city will have to be moved?
Is there a reputable hedging market for that outcome?
A few centuries. The biggest sea level rise will be at the end, the effect will be non linear. Long after we decarbonize, sea level will keep rising.
some are a lot earlier than others. New Orleans and Most of Florida are already having problems (especially when a hurricane creates a big storm surge).
I think that 'large mountain estimate' depends heavily on atmosphere-ocean mixing rates, doesn't it? IIRC, ocean circulation takes about ~2000 years to mix the oceans.
Ocean acidification is a local near-surface phenomenon caused by the oceans absorbing the higher levels of CO2 and pulling the carbonate equilibrium to the left, so to speak. CO2(atm) <-> (H2CO3) <-> (HCO3)- <-> (CO3)-2 -> CaCO3 precipitate ?
I don't know a whole lot about this, but it seems you'd have to keep doing this steadily and gradually for > 100 years (maybe 1000 years) at global scale to get that effect? ...and that's assuming no more fossil fuel combustion was taking place?
As a mitigation for coral reefs, oyster beds etc. it seems to have more immediate value.
Ocean acidification is a local near-surface phenomenon caused by the oceans absorbing the higher levels of CO2 and pulling the carbonate equilibrium to the left, so to speak. CO2(atm) <-> (H2CO3) <-> (HCO3)- <-> (CO3)-2 -> CaCO3 precipitate ?
I don't know a whole lot about this, but it seems you'd have to keep doing this steadily and gradually for > 100 years (maybe 1000 years) at global scale to get that effect? ...and that's assuming no more fossil fuel combustion was taking place?
As a mitigation for coral reefs, oyster beds etc. it seems to have more immediate value.
No, we'd need to dissolve that amount into the mix layer (call it the top 50m, for argument's sake), which takes a few months to equilibriate with the atmosphere through that carbonate chemistry. But, if one managed to do it all at once (not sure how), it would only take a few months.
One would want to avoid downwelling regions that get sucked into deep ocean circulation before reaching equilibrium (e.g. the north atlantic), that alkalinity would take a long time to come back up and be useful.
One would want to avoid downwelling regions that get sucked into deep ocean circulation before reaching equilibrium (e.g. the north atlantic), that alkalinity would take a long time to come back up and be useful.
The kicker for this particular method is at the end:
> "Caldeira’s team wrote that its approach would be “infeasible” as a global solution. That’s because it’s difficult to make alkaline additives without emitting CO2, he says. Heating limestone to make lime, for example, releases so much of the gas that it partially offsets the increased uptake by the ocean. Even if low-emission lime could be made, it would probably be too costly to dump into the ocean."
> "Caldeira’s team wrote that its approach would be “infeasible” as a global solution. That’s because it’s difficult to make alkaline additives without emitting CO2, he says. Heating limestone to make lime, for example, releases so much of the gas that it partially offsets the increased uptake by the ocean. Even if low-emission lime could be made, it would probably be too costly to dump into the ocean."
Sad...
That doesn't mean it's useless though.
> Caldeira and colleagues added sodium hydroxide—also known as lye and an ingredient in many soaps and detergents—to a part of Australia’s Great Barrier Reef. They found it raised pH levels nearly to preindustrial levels, allowing the natural calcification of the reef to increase.
> Caldeira and colleagues added sodium hydroxide—also known as lye and an ingredient in many soaps and detergents—to a part of Australia’s Great Barrier Reef. They found it raised pH levels nearly to preindustrial levels, allowing the natural calcification of the reef to increase.
I'm glad to hear about this, ocean acidification does not get enough attention, which has always been weird to me since it seems to be linked to both CO2 emissions and bad things happening in ways that are much harder to deny.
> releases so much of the gas that it partially offsets the increased uptake by the ocean
Even that is a rather optimistic take... My Chemistry knowledge suggests it more than offsets what is taken up by the ocean...
Even that is a rather optimistic take... My Chemistry knowledge suggests it more than offsets what is taken up by the ocean...
Cost aside, it is possible to calcine limestone with green electricity, and capture the outbound CO2.
As mentioned, this is still quite costly, but it's likely a hurdle we will need to cross regardless to get to green cement.
As mentioned, this is still quite costly, but it's likely a hurdle we will need to cross regardless to get to green cement.
Olivine is readily abundant in the upper mantle and has similar decarbonizing and deacidifying effects. Theory and pilot programs suggest there's enough to completely offset the world's carbon output with relatively few mines and tropical coastlines.
https://www.vesta.earth/
https://www.vesta.earth/
Note that there's a bit of a problem with fertilizing the oceans with iron (the other strategy mentioned in the article) to cause phytoplankton blooms which then sink to the seabed, thus removing carbon from the atmosphere. It's that microbes in the water column steadily break down sinking biomass, sucking down free oxygen levels as they do so.
This results in large zones of anoxic bottom water, or at least hypoxic, aka 'dead zones' as in the Gulf of Mexico. These zones were much more widespread 100 million years ago when many oil and gas-bearing sediments were being laid down, but turning much of our modern ocean into a sulfurous stinking anoxic zone is not the brightest idea.
This results in large zones of anoxic bottom water, or at least hypoxic, aka 'dead zones' as in the Gulf of Mexico. These zones were much more widespread 100 million years ago when many oil and gas-bearing sediments were being laid down, but turning much of our modern ocean into a sulfurous stinking anoxic zone is not the brightest idea.
Feels like an appropriate tool to use in conjunction with tropospheric sulphur release (which while extremely effective at offsetting carbon causes some politically intractable…er…minor…acid rain) to flatten the curve on climate change in the next five years until more energy intensive carbon draw down solutions can be deployed. Ie harnessing fuel from the atmosphere using fusion power.
I forget the details but I've seen work on doing that sulfur release plan with something else that doesn't cause acid rain. The main reason for the initial focus on sulphur dioxide is that we've already seen it done, by volcanoes.
Another method seems to be to weather silicate rock on land, it reacts with water and CO2, dissolved bicarbonates are produced and washed into the oceans where they form carbon rich sediments.
This can be used as complimentary fertilizer on agricultural land.
This can be used as complimentary fertilizer on agricultural land.
[deleted]
Oh dear, I feel it would be better to work on why the ocean is becoming more acidic rather than mixing in chemicals to stop it!! I hope they’re doing the former with as much enthusiasm as the latter
When you know exactly how things will be affected, then feel free to make changes.
When you don't know exactly how things will be affected, then you shouldn't make changes.
This action was the second case and it was only done for monetary concerns. This wasn't motivated by environmental concerns, it was motivated by profit. And the profit motive is exactly what got this planet in to its climate situation.
When you don't know exactly how things will be affected, then you shouldn't make changes.
This action was the second case and it was only done for monetary concerns. This wasn't motivated by environmental concerns, it was motivated by profit. And the profit motive is exactly what got this planet in to its climate situation.
> When you don't know exactly how things will be affected, then you shouldn't make changes.
That’s an impossible standard to uphold. I don’t disagree with your overall premise, but the world is simply too complex to understand all of the ramifications of anything meaningful.
That’s an impossible standard to uphold. I don’t disagree with your overall premise, but the world is simply too complex to understand all of the ramifications of anything meaningful.
Nice! This is one of the most succinct explanations of why socialism always fails - too much complexity to dictate all actions.
I don't know the exact impacts of changing our current climate trajectory, or implementing green technology, so better to stick with our current course.
>When you don't know exactly how things will be affected, then you shouldn't make changes.
We can hold to your standard the moment we hold to that standard for other activities, such as burning fossil fuels in the first place.
We can hold to your standard the moment we hold to that standard for other activities, such as burning fossil fuels in the first place.
[deleted]
Precaution seems appropriate but aren’t we doing things we don’t understand anyway? That seems like the default. Surely we can’t roll back all of humanity, but maybe we can stand athwart history and yell “stop!” if only in hopes to slow down the stupid.
Are you making a general point or one specific to this? And is your first point (precautionary principle) connected to your second point (financial motivations)? The experiment referenced in the article is a small scale test, so it seems to me that it is following the precautionary principle. As for if the financial motivations are an issue, I don't know.
Are you just being snarky and anti-establishment or do you have a concrete criticism to make? Please make it if you do.
Are you just being snarky and anti-establishment or do you have a concrete criticism to make? Please make it if you do.
Every time you drive a car or get in an airplane you're in the "When you don't know exactly how things will be affected" category, you're adding more Co2 to the atmosphere and thus warming the planet at a never seen before rate. We don't know exactly how things will be affected.
...but trying to reverse some of this is bad now?
From reading the article, it seems hard to say the experiment sounded negative?
...but trying to reverse some of this is bad now?
From reading the article, it seems hard to say the experiment sounded negative?
Read Elizabeth Kolbert’s “Under A White Sky” for a history of how best-intentioned interventions into ecologies have consistently backfired, in each case the unpredictable and far reaching complexity of the system was thrown out of balance.
I think the commenter’s admonition may have been expressing the the same lesson: its hubristic to “fix” systems with hacks like this; whereas carbon drawdown is not a hack, because it operates within the mechanism of imbalance itself.
For my part, this article had so little reporting of the complexity of ocean ecosystems and the potential dangers, not to mention how it buried the bit about how carbon intensive lye is (the same reason that makes concrete have such a huge carbon footprint) that it read like a puff piece.
I think the commenter’s admonition may have been expressing the the same lesson: its hubristic to “fix” systems with hacks like this; whereas carbon drawdown is not a hack, because it operates within the mechanism of imbalance itself.
For my part, this article had so little reporting of the complexity of ocean ecosystems and the potential dangers, not to mention how it buried the bit about how carbon intensive lye is (the same reason that makes concrete have such a huge carbon footprint) that it read like a puff piece.
There has been quite a lot of interest in Ocean Alkalinity Enhancement (OAE) in the last few years.
This is kind of an unfortunate title, as "geoengineering" (while not wrong) has a very negative connotation in non-scientific publications. Presenting OAE as ocean acidification remediation would have been a much nicer way to drive adoption.
As a side note, lime can be very problematic under some conditions (parasitic CaCO3 precipitation can cause a net release of CO2). But ultramafic rock is alkaline and everywhere. It tuns out you need approximately one large mountain dissolved into the ocean to reverse climate change (neutralize ocean acidification and causes the ocean to take up any extra CO2 in the atmosphere). Or you can just remove acidity from the ocean using solar power, and pour it on rocks somewhere.