Minor point: “Seawater is, of course, full of salt, and salt is a buffer; its chloride ions sop up hydrogen ions, keeping the ocean from getting as acidic as freshwater with dissolved CO2 would”
This is not true. Chloride ions don’t act as a buffer, but other organic ions (carbonate and bicarbonate , mainly) would.
You said that there’s 3300 Gt of CO2 in the atmosphere and 38000 Gt of carbon in the ocean but said that the stock of carbon in the ocean dwarfs the amount in the atmosphere by 44x - was that an error or am I missing something? Seems more like 11.5x
Big picture, I see the availability of such massively scalable options as a big reason for optimism on climate change.
Any thoughts on how costly these approaches are likely to be compared to direct air capture using solar, which seems like it will become the default benchmark given how much overbuild of solar energy we should expect over the next couple of decades?
the handful of numbers i saw made mineral-based mCDR look cheaper but i didn't have a chance to check if they build in predictions of a falling cost of electricity via solar
Thanks for explaining this! From the title alone, I thought the proposal was going to be a way to speed up ocean acidification under the guess that its negative consequences are less bad than the negative consequences of atmospheric carbon. I’m glad to see that some of these proposals actually effectively work in the other direction, by finding ways to alkalinize the ocean, so that it sucks carbon out of the air faster.
Of course, the same questions apply to all of them - is the thing we are proposing actually less bad than leaving the carbon in the atmosphere, or omitting the human activity that would emit the carbon?
White Sands national park is pretty much all gypsum. Easily dissolved in seawater. No grinding necessary. Heck, the entire Chihuahuan desert could work.
Based on the title, I thought this was about reducing CO2 in oceans (to counteract human-caused increases).
Then I realized this is about using the ocean to take up atmospheric CO2.
So now I’ll go back and read more about whether/how ocean CO2 increases are a problem and how likely caused by human emissions.
I suppose some techniques above address both ocean and atmospheric CO2 removal.
I’m often surprised that - to the extent increased atmospheric CO2 is a major risk and problem - stronger consideration is not given to Solar Radiation Management via sulphur compounds in the upper atmosphere; one relationship we understand well in modeling climate change is between gas/compound concentrations and spectral properties, whether CO2 or SRM compounds. One counterargument is that SRM is that it doesn’t solve ocean acidification (which brings me back to my shortcomings and need to understand oceans more).
Fantastic overview of this potential solution! I hope you have the ear of environmental futurists and politicians. An idea: Give a presentation at The Long Now? https://longnow.org/
One thing I don’t understand is why permits are needed. If I dumped a ship full of iron filings into the ocean, who would know or care? Isn’t this the whole point of libertarian seasteads? Nobody owns the ocean
Minor point: “Seawater is, of course, full of salt, and salt is a buffer; its chloride ions sop up hydrogen ions, keeping the ocean from getting as acidic as freshwater with dissolved CO2 would”
This is not true. Chloride ions don’t act as a buffer, but other organic ions (carbonate and bicarbonate , mainly) would.
I was about to comment that; HCl's a strong acid, the basicity of its conjugate base should be minimal.
There's some sulfate in there too, but it's not that basic either.
You said that there’s 3300 Gt of CO2 in the atmosphere and 38000 Gt of carbon in the ocean but said that the stock of carbon in the ocean dwarfs the amount in the atmosphere by 44x - was that an error or am I missing something? Seems more like 11.5x
To convert from carbon (C) to carbon dioxide (CO2):
Use the formula that one ton of carbon = 3.67 tonnes of carbon dioxide.
So divide the 3,300 by 3.67 to get 899 GT carbon in the atmosphere (currently in the form of 3,300 GT of CO2)
38,000 / 899 = 42.3
I could see the 44x coming from some slightly different input assumptions.
yep, this is a conversion between CO2 and carbon issue
Big picture, I see the availability of such massively scalable options as a big reason for optimism on climate change.
Any thoughts on how costly these approaches are likely to be compared to direct air capture using solar, which seems like it will become the default benchmark given how much overbuild of solar energy we should expect over the next couple of decades?
the handful of numbers i saw made mineral-based mCDR look cheaper but i didn't have a chance to check if they build in predictions of a falling cost of electricity via solar
Thanks for explaining this! From the title alone, I thought the proposal was going to be a way to speed up ocean acidification under the guess that its negative consequences are less bad than the negative consequences of atmospheric carbon. I’m glad to see that some of these proposals actually effectively work in the other direction, by finding ways to alkalinize the ocean, so that it sucks carbon out of the air faster.
Of course, the same questions apply to all of them - is the thing we are proposing actually less bad than leaving the carbon in the atmosphere, or omitting the human activity that would emit the carbon?
White Sands national park is pretty much all gypsum. Easily dissolved in seawater. No grinding necessary. Heck, the entire Chihuahuan desert could work.
Thanks for writing this piece.
Based on the title, I thought this was about reducing CO2 in oceans (to counteract human-caused increases).
Then I realized this is about using the ocean to take up atmospheric CO2.
So now I’ll go back and read more about whether/how ocean CO2 increases are a problem and how likely caused by human emissions.
I suppose some techniques above address both ocean and atmospheric CO2 removal.
I’m often surprised that - to the extent increased atmospheric CO2 is a major risk and problem - stronger consideration is not given to Solar Radiation Management via sulphur compounds in the upper atmosphere; one relationship we understand well in modeling climate change is between gas/compound concentrations and spectral properties, whether CO2 or SRM compounds. One counterargument is that SRM is that it doesn’t solve ocean acidification (which brings me back to my shortcomings and need to understand oceans more).
Uhm... so the ocean already does this by itself. Ocean acidification is one of the consequences.
Fantastic overview of this potential solution! I hope you have the ear of environmental futurists and politicians. An idea: Give a presentation at The Long Now? https://longnow.org/
One thing I don’t understand is why permits are needed. If I dumped a ship full of iron filings into the ocean, who would know or care? Isn’t this the whole point of libertarian seasteads? Nobody owns the ocean
Yip yip hura Jura