@JemBishop You could also remove bicarbonate from seawater which might be more promising — and scale faster.

@B I hope someone with more expertise can weigh in but my understanding is that it doesn't count because trees don't quite permanently remove carbon from the atmosphere. When a tree dies and decays it emits carbon again. Something like that. But it would be good to get definitive clarification on this, I agree!

@dreev depends what you do with the wood when it dies!

Meta: What's up with the whitespace here? Did you hit enter a bunch or did the website glitch out?

@Mqrius This is not the first comment I've encountered in the last 24 hrs with lots of whitespace post text, so, it might be a bug.

@Mqrius It's a bug on mobile

@ElliotDavies I'm seeing it on the web browser and not mobile

@firstuserhere laptop's web browser*

@firstuserhere The bug is on the commenters' side, I imagine @Bidden wrote the comment on mobile

@Mqrius I'm definitely open to suggestions here. The original spirit of the prediction was for purposes of assessing how critical it is to reduce emissions. If carbon capture is expected to get cost-effective enough then reducing emissions now is less critical. Presumably. So I'm thinking that anything that permanently un-emits carbon should count. Does that make sense?

PS: And, to clarify, anything that just prevents emission in the first place, including things smokestack scrubbing that capture carbon before it's actually emitted, would not count.

(I've now updated the description and still need to decide whether to update the title to say "carbon capture" rather than "carbon removal". Opinions solicited!)

Personally I see a synthetic fuel economy as the most likely path to carbon removal and CO2 reduction, so it makes sense to me that it would count. It's a valid market either way as long as the decision criteria are clear beforehand. Pure carbon removal playing a big role by itself would be a lower chance than synthetic fuels taking off and doing carbon removal as a side effect.

@Mqrius Nodding-emoji. But are we on the same page about how this market is about directly reducing atmospheric CO2 concentrations by literally pulling CO2 back out of the air?

@dreev yeah that makes sense to me.

I'll take the other side of that bet. No, the economics aren't there… yet. But if carbon removal follows the same curve as e.g. solar panels, then in a decade it will. (As Stripe Climate argues here: https://stripe.com/climate#:~:text=Early%20purchasers%20can,and%20solar%20panels.)

It's hard to see how climate change is solved without using carbon removal or similar. Coordinating to halt emissions of carbon is a pie in the sky pipe dream. Social coordination problems are really hard, way harder than is intuitively obvious—your intuitions for how hard such things are were tuned for a band of tens of people, not planet-spanning civilization—and technological solutions are what modern society is at least somewhat good at.

No, it's not a sure thing, and I wouldn't want to bet too much above 70% or so. Lots of things can happen, including some other technological solution or set of solutions. But this is by far the leading candidate at the moment.

@zzq Direct-air carbon capture needs a lot of energy. It can get cheaper than now but will reach a limit as long as energy is not free.

Using fossil carbon as energy from one side, rejecting it from the atmosphere and from the other side using energy to capture it can't be efficient. Even when taking CO2 at the source of a power plant, it's considered expensive.

As for the coordination problem, why would some people pay to capture CO2 for common good while others put it there for their own profit ? I mean at the full scale it would be needed, not for symbolic use as currently.

why would some people pay to capture CO2 for common good while others put it there for their own profit

That's the classic type of coordination problem that governments are good at solving - tax carbon usage and then do the carbon capturing with the funds. If set up properly, it can be precisely revenue neutral and carbon neutral. Assuming the technology is solved (big assumption), the main problem is that carbon crosses borders. Hopefully treaties can solve that though.

Coordination can be hard, but it's not impossible with top down management.

@Gabrielle If they can coordinate for that, they can coordinate to reduce emissions. If they can set a tax carbon big enough and collect it globally, this will cause the needed reduction.

@Zardoru I think taxing + carbon capture would be a lot more politically feasible, even though it's a worse overall solution, because people are too addicted to goods and processes that use carbon.

1. Degrees C (description updated; thanks!)

2. That would definitely yield a YES resolution.

3. I meant this to be about direct air capture specifically.

@dreev direct air only? Lemme go sell my yes

The spirit of the prediction is whether there's a remotely reasonable case to be made for business-as-usual greenhouse gas emissions, counting on future technology to then reduce atmospheric CO2 concentrations. What else besides direct-air capture makes sense to count?

(An example of something I definitely don't want to count for this question is any kind of geoengineering that directly cools the earth without reducing greenhouse gases in the atmosphere.)

@dreev tiling the ocean with seaweed.

space mirrors would not count for this question, but I think space mirrors are a really good case for buisiness-as-usual

@Sinclair Agreed that space mirrors don't count for this question (and they're a bad argument for business-as-usual even if they would definitely cool the earth because cooling the earth without reducing CO2 concentrations may have severe unintended consequences).

For tiling the ocean with seaweed to pull CO2 out of the air, maybe that's in the spirit of the question? I'm now realizing that the criterion for success here should probably be CO2 concentration in the atmosphere instead of global temperature.

@dreev direct air capture is always going to be hard as you are trying to collect a trace gas.

Promising tech I've worked on: enhanced mineralisation - left over rock dust from igneous rock quarries, spread on fields or verges. Normally it mineralises co2 slowly, but in the top soil all the growing things means there's water and a local increased partial pressure of co2, so it's quick.

Solid sequestration in the form of buried timber or scattered biochar have good potential, more so if we can incorporate them into useful products to scale. Biochar in particular is a way to stabilise biomass waste for a century or so. We're looking at timber building, then waste wood gets mycelium or biochar treatment.

Capture at chimney is still much better than direct air. It might be plugged onto existing waste incinerator/cement/steel works, or might be integrated into BECCS - grow biomass to capture vco2, burn it for energy, sequester the gas. We've better uses for that biomass than just burning it though.

Seaweed sequestration is a big site of research, but the challenge is proving sequestion. It might become a biomass production machine, tethered off the offshore wind turbines and used for food, oils, fats, fuel or land sequestration.

On reflection it makes sense that no one has strong opinions on the end date. 2050 is a fine proxy for "eventually" so we'll go with that.

But part of the spirit of this prediction is whether stripe.com/climate is a smart bet so we don't want to push the horizon out so far that this could technically resolve YES due to far-future technology that no one could anticipate. In that case it may well be wrong-headed to attempt it now; the current carbon capture naysayers would be correct in that case.

@MichaelRucker Excellent question! Ok, so, normally you buy shares of YES that pay out $1 each if the thing happens and $0 if it doesn't. (See the first section of https://astralcodexten.substack.com/p/prediction-market-faq for a nice primer on these basics.) But what if the thing kind of happens? You can have the YES shares pay out at X% of $1 if the thing "X% happened"!

In this case maybe the market probability started at 50% because we had no clue if the answer would turn out to be yes. Then a few years later we still don't know but we're starting to have a pretty good guess that the answer is yes. Maybe there's now an 80% chance. So if you predicted YES back in 2022 then you've been somewhat proven right. You bought those shares at $0.50 and now they're worth $0.80 each. So you've made money. Not as much as if you waited for a definitive YES but maybe we don't want to wait that long. It's still theoretically perfectly fair. (Insert a bunch of caveats here.)

But also, now that Manifold loans you back the mana you tie up in long-term markets we probably don't need that clause anymore. We can just keep this market open until we have a definitive answer, which is my new tentative plan.

@dreev Ah OK. Thanks! So essentially that means everyone sells / is forced to sell their shares at that time and receive whatever they are worth then ... right?

@M No no, nothing has to happen by that date. This was meant to solve the problem of long-term prediction markets (before the loan feature!) by predicting the nearer-future consensus on the farther-future outcome.

@tb That would be a NO resolution.

@tb Good question. Let's define it as scientific consensus that carbon removal was (or is predicted to be, since this market will end early) responsible for half a degree less warming that we'd otherwise see.

The idea is to predict whether carbon capture will get cheap enough to do at a big enough scale to matter and be worthwhile.