If you don't have anything to pyrolyse, use a sodium or potassium hydroxide wet scrubber to extract it from ambient air and recover it from the solution with burnt lime; it preferentially bonds to the carbonate, becomes nearly insoluble; you take the lime stone powder, heat it with a high temperature blow dryer until the carbon dioxide cooks out (you can use pure carbon dioxide atmosphere for that! Just let out excess buildup of CO2 pressure to your output cooler/storage.), have regenerated the burnt lime, take the resulting CO2 and hydrogen to perform water gas shift to turn the mix into CO and H2O, condense out the H2O, then use the CO + H2 mix for your Fischer-Tropsch synthesis.
You can use incineration facilities to tap off concentrated CO2 and mine landfills until they are empty to keep the incinerators fed to get the CO2 possibly-cheaper than from the direct air capture units.
Start by using more solar cell glass laminate for exterior surfaces of new construction and as roofs over whatever parking lots you do want to keep around longer-term.
Synthetic non-fossil fuel is going to need plenty of electricity and probably much of that "just" to electrolyze water into hydrogen which is reasonable for seasonal energy "storage" (run them during the high-solar 25~50% of the year, use underground caverns (former natural gas wells) or liquify it to store for the winter, run the synthesis plant that consumes it year-round. Don't just burn the hydrogen in power plants, though you can keep existing fossil fuel plants around for a while to run them during the worst week or two of an average winter. But expect the power to be as expensive as each kWh you get today from a small gasoline generator fueled with fully-taxed highway gasoline...
Should every Chinese and Indian visit Venice, even though it destroys the city little by little? Should we send things as futile as watermelons by plane?
Of course, the market wills it so some may think that it must happen, yet I feel that the globalisation and massification of everything made the world a less diverse and interesting place overall.
Me neither, but that doesn't stop me from celebrating possible breakthroughs in decarbonisation.
Went to Venice by night train 15 years ago, would definitely recommend.
Conversely, however, perhaps we should question Europeans massively going to Phuket.
Who are you to dictate where Chinese and Indians can and cannot visit or enjoy delicious watermelons?
If someone wants to eat a watermelon like a dirty slave that is their business and you are not going to deny them that right. This is pure insanity.
China and India are the biggest domestic aircraft markets in the world. The manufacturers literally cannot keep up with the demand. If trains were more effective they would have built them already. If California has taught us anything it's that implementation of high speed rail is a joke.
I am appalled at the level of delusion and craziness in these responses, it would take a year to respond to them all.
Air travel is not going anywhere and we are not setting society back 100 years on account of dubious climate histrionics.
Want to save the environment?
Ditch smartphones (future e-waste) and all their useless apps (and resource-sucking infra) we could all live without tomorrow.
Turns out we were as effective in moving goods and services and leisure travel in 2008 as we are today.
We just couldn't post to social media about how uncomfortable the airplane seat was and how the onboard Wi-Fi sucked.
Well they're more convenient by virtue of being faster. The well off will inevitably pay for convenience if allowed.
> If California has taught us anything it's that implementation of high speed rail is a joke.
The only thing California stands as an example of in that regard is political dysfunction. A hypothetical benevolent dictator could have built out high speed rail there on time and on budget.
> I am appalled at the level of delusion and craziness in these responses
Has it not occurred to you that maybe that's a red flag that perhaps your own views or emotional state are a bit off?
> on account of dubious climate histrionics.
An empty dismissal of a vague and poorly defined (on your part) concept. How about engaging with a real position instead of name calling a straw man?
> Ditch smartphones (future e-waste)
And what do you suppose the combined total environmental impact is for those globally compared to other categories?
Honestly I respect China a lot and it’s hard not to respect them when it comes to getting infra projects done, be it roads, trains, or whatever. But it’s not a system that has any overlap with the rights in our Constitution. Even Europeans expect more rights from their governments.
I am 100% for decarbonization as fast as possible.
BTW Law of Conservation of Energy will be applied to coconut-based energy as well.
Vaclav Smil mentions in his book that we should consume less.
I see so many cheap weekender air tickets… it’s almost impossible to resist the temptation.
Annually 5 billions people travel by plane…
I.e. measures like massive taxation (also for private jets of course).
As another example, the amount of greenhouse gas emissions from airplanes is several times less than the amount of methane that leaks out of natural gas pipelines every year (here I'm weighting emissions by their global warming impact). The overwhelming majority of those leaks can be prevented with minimal effort, but industry hasn't been incentivized to do so. Maybe before we start banning tourism, we have some inspectors checking pipelines for pinhole leaks?
Climate change deniers and polluters want to paint the environmental movement as a bunch of neo-Puritans that deride anything that isn’t the bare minimum of subsistence as immoral. And I worry they’ve done this for so long that some supporters of the environment are starting to believe the lie.
It's a real problem because it has really bad political optics. And results in obsessing about 'fixing' inconsequential things or solutions that make things worse.
Seems like he’s looking forward to a dictatorship that will just tell us all what we’re allowed to do, without the burdensome need for our dumb pleb voices to be heard. Maybe they could call the folks who enforce the policy the “Klimate Governing Board.”
And other countries will also choose to keep their privileges and climate change will not be reduced anyway.
These people are so out of touch it’s bananas.
And yes, no tourist income. It's dirty money.
Externalities can be made to bear a cost.
If the use case does not require fossil fuels, certainly, carry on. Same if your biofuel isn’t going to cause the Amazon to be clear cut and can be economically produced at scale. But until then, have to aggressively impair the consumption of fossil fuels, because it’s only going to keep getting hotter, year after year, long after we reach net zero (which is still a decade or two away). Maybe one day we’ll have a mechanism to sequester carbon, and enough low carbon energy to suck all of the CO2 emitted since the industrial revolution started out of the atmosphere for long term, stable storage to mitigate climate change. But not today, and therefore, these are the facts that must drive policy until the facts change.
Climeworks' capture fails to cover its own emissions - https://news.ycombinator.com/item?id=44017317 - May 2025
> Al Gore gave a TED talk in 2023 where he discussed the carbon capture and disposal industry and specifically mentioned Climeworks. He made fun of the company, calling the capture industry nothing more than a cover for oil and gas companies to keep their businesses afloat.
Even if you don’t like Al Gore, the math remains the math.
The cost applied to externalities can be spent to amend the specific damage, which is sometimes impossible, or can be commensurate to the estimate damage in order to create different benefit.
> indulgence
I concour with the analysis, but not necessarily with the moral evaluation. I have already mentioned nearby that money is a token to be spent on freedom in a framework of choice in allocation: Economics, science of Optimization, is the science of the management of Scarcity to some authors - and that scarcity is structural, existential (as evident in the case of Time). The purpose of resources is to invest them according to preference - some choices more loaded, but the computation compares the values of said "load" with the "preference" and the "resource (money etc.)".
The actual rebuttal: if you had to go "black vs white" in preferences, vs the continuous framework I proposed, than heating for example would be a problem - an externality bearing investment that we could not compensate with a reversal of the damage. But should we do without heating? You yourself defend touristic travel. Where can we put a threshold? At that point, it is best to quantify damages and charge the externalities.
Electricity->Batteries, renewables, geothermal, hydro, transmission, cross country interconnectors
HVAC->Heat pumps, low carbon district heating, insulation, sand heat batteries
Mobility->Electric vehicles, bikes, scooters, light rail, heavy duty electric vehicles
Marine traffic->Low carbon produced methanol or ammonia
For air travel that must remain and cannot be replaced with an electrified or low carbon alternative (until low carbon solutions exist), the component that must remain be made as efficient as possible. Regardless of wealth, you fly commercial, just like everyone takes the subway, regardless of wealth or status, in cities with high quality mass transit. Your need is met, just within our collective societal tolerance for the harm incurred for the travel desired (Point A->B).
We may disagree, and that’s fine. I believe the climate data is clear as an input to this decisioning. Whether you’re wealthy should not be a factor in outsized carbon emissions (private jet travel, specifically) simply because the socioeconomic system is defective on this. I assume the appetite for this goes up as climate change consequences become more dire, compelling more appetite for extreme actions to course correct.
There's nothing except the political preventing the governments of the world imposing the unpalatable price on the market and policing the capture operations for net effectiveness.
Curious -- what speed are you assuming for such a high speed rail?
Within the scope of land travel, it’s clear it can be built. If it isn’t built, of course, that’s a choice. But it’s a lie to say it cannot be done.
Even at 300mph, which IIRC is much faster than normal operations on existing system, transcontinental travel becomes "too slow." The opposition would be insurmountable to making it take 12+ hours to travel from NYC to LA, for example.
Effectively would split the continent in a way that it hasn't been for generations. Rountes like NYC<->Chicago would get annoyingly slower, but long routes like DC<->Seattle would become an "almost never" trip by train @ 200mph (even assuming direct, as-the-crow-flies). Practically, you're talking "east coast to Asia" durations to cross the continent. Non-starter.
Disclaimer: I love trains. I want high speed trains deployed widely in the US.
The good news is that 300 kmh is really fast, and rail is usually much more time-efficient at the endpoints (i.e. stations are more central and there's less waiting). In China, Shanghai-Beijing (approximately LA to San Francisco) is now possible in 4h30. Given the endpoint advantage, that is more than competitive with plane travel, and much more pleasant.
As of this year, China also has a high-speed capsule sleeper that gets you from Beijing to Guangzhou (CORRECTION: 1875 km) in 12 hours at an average speed of 180 kmh. It's still night travel, not every American would be interested. But it shows what's possible.
I don't understand. It looks like the Chinese route is ~1200 miles and the US route is about 2500 miles. At the same 180kmh, wouldn't that imply a full 24 hours on a train?
re: LA-SF, I do think HSR could make a big dent on each side of the continent. But the reality is Americans are accustomed to crossing the entire continent quickly, and HSR is not yet a substitute for that.
Tangential - the source of my faulty research was Claude Haiku 4.5, which I will quote verbatim: "Two major US cities separated by approximately 2230 km are New York City, New York and Los Angeles, California." I know that figure is too low but believed it anyway. I've just asked for better figures and it's completely unable to answer accurately. Well well.
It already takes 6 hours to fly. Add in security, checked bags, getting to and from the airport and it's close to 10 hours. Also you waste a day or ruin a night's sleep on the redeye.
Compared to that an overnight train with a bed sounds delightful. People could do almost-day-trips, coast-to-coast, with no ill effects. Leave LA tonight, shop/sightsee/eat all day in NYC, take in a show, hop on the late train back to LA the following day. This is pretty near impossible today unless you have a private jet.
10 hours is still significantly faster than a hypothetical HSR. Remember that it would also have to stop along the way. Secon, not everyone lives/is traveling to a place that is near a hypothetical train station; you have to keep in mind that American cities tend toward sprawl. HSR leaving from e.g. downtown LA would still be less convenient for e.g. the folks who live in the Valley. It's definitely not a 10-hour excursion for many people to transit the country (source: I did this for years for work).
> Also you waste a day or ruin a night's sleep on the redeye.
Highly dependent on the individual & service class. But the point of this is you're actually physically there in less time.
> Leave LA tonight, shop/sightsee/eat all day in NYC, take in a show, hop on the late train back to LA the following day. This is pretty near impossible today unless you have a private jet.
You're going to get a lot of pushback from people who have been to weddings on the other side of the continent, since they will have done this. Most of them do not have private jets, it's just a common thing Americans do.
Keep in mind these old downtown stations built in 1900 won’t be able to handle the kind of passenger counts that would “need” to be shifted from the airports, so don’t delude yourself into thinking you wouldn’t need big train stations built in the outskirts, crowded and irritating to get to, like we have with modern airports.
Your day trip thing sounds even more confusing. That itinerary that’s “near impossible” with fast flight becomes more impossible with trains that take 2-3x longer. Also, sleeper train tickets are incredibly expensive compared to coach, because of how much space they take up and the cost of upkeep for these little suites. They’re always going to be expensive, like the redeye flight on a lie-flat bed. So again, no different than what we have today, just much, much slower and less accessible to the masses.
At least the future can default on sovereign debt, it cannot default on the energy and resources required to repair physical systems required for survival, that debt is the ultimate recourse debt. There is nowhere to run from it.
https://climatechangetracker.org/climate-change-progress/cur...
https://actuaries.org.uk/media/ni4erlna/planetary-solvency.p... (page 32 risk impact matrix)
(day job is risk assessment and management, and the lens through which I see and model this entire system)
Which sucks, because I really would go for a US high-speed rail network.
> https://www.heartaerospace.com/newsroom/heart-aerospace-comp...