… this points to the importance of studying the effects of deliberate atmospheric aerosol injections… I think calcium carbonate is very promising—but we need to start doing tests asap to learn the effects.
And you're going to do this for the rest of the forseeable future?
Way more than anything else it sounds like a cop out to avoid dealing with the long term consequences of what we put out there now and to keep pumping oil
Yes, I think it will be taking place for the remainder of our lifetimes.
Solar growth is likely to remain exponential for the next decade or so, which will create a number of new opportunities. Other energy sources will also come online. But fossil fuels are unlikely to be regulated away, globally. We are also likely past some serious tipping points— so I prefer to figure out ASAP whether stratospheric aerosol injections are a viable tactic for preventing the melting of permafrost, for instance.
It seems pretty wild that we would even think about deliberate climate engineering. We're dealing with an incredibly complex system, the only place we have to live, and one where "harmless" actions before have had devastating unforeseen effects decades later. The lesson we should have learned we need to stop pumping stuff into the atmosphere and oceans until something bad happens, not "let's pump more stuff into the atmosphere."
Some random small group of people get to take these risks for all humanity? No thanks.
It just seems collectively insane to NOT be researching the hell out of the possibility that we could regulate our global heat balance issues for a cost of a few tens of billions of dollars a year.
Especially when the alternative solution to global warming is… degrowth. Which is just not going to work functionally as a political policy in a competitive world.
Fossil fuel use will decrease significantly… eventually.
Btw, did you know that if the USA replaced farmland currently growing biofuels with solar, that land area would produce 4x the current total electricity use of the entire nation?
We need to buy time — we can’t let the permafrost melt because “stupid humans deserve it”
Thing is we're not stopping. So given the fact that we are not stopping and won't stop, climate engineering starts to look like a decent Sr ond choice. I mean it doesn't take much for it to be better than nothing.
nice em dash -- how do I generate that in the text box?
but you're burying the lede: "We are also likely past some serious tipping points—" == we're doomed, just slowly, and we desperately need to be doing something to slow down or stop this metaphorical bus before it falls off a cliff
This is a bad cop-out, honestly. Every macOS for at least 11 years—and iPhones for a similar length of time—have automatically changed dash dash space to an em-dash. Edit -> Substitutions -> Smart Dashes to toggle the behavior. Here's an 11-year-old video discussing the feature. https://www.youtube.com/watch?v=nZrkDetAmpE
I see the replies to the literal question, but I think the parent was pointing out the possibility of the grandparent post being AI generated. The em dash is one of the common indicators.
> sounds like a cop out to avoid dealing with the long term consequences of what we put out there now and to keep pumping oil
Any practical solution will consist of a wide array of approaches executed in parallel.
Talking about suddenly getting the whole world to stop using oil is a hypothetical thought exercise. It’s not going to happen. We have to be looking at all of the approaches together, including some lessening of fossil fuel use.
I think we need to do this until we develop large scale underground CO₂ sequestration.
Unfortunately even if/when we completely stop producing CO₂, it takes at least several centuries until levels go fully back down to natural levels by themselves.
Pumping SO₂ into the stratosphere should be able to regulate global temperatures to reasonable levels while we develop effective CO₂ sequestration.
Unfortunately SO₂ injection is incredibly controversial, as it triggers the "don't mess with nature" taboo, especially among people who have seen Jurassic Park, and affects the whole planet, including those who don't want it.
We do actually know that SO₂ breaks down in the stratosphere in 1-2 years, because we've studied when volcanoes injects it. It also doesn't cause acid rain because it's above the rain cycle.
But these facts are very hard to get across to people.
That SO₂ breaks down so quickly is one of the reasons SO₂ injection is probably not a good idea.
Suppose we start putting enough SO₂ in the stratosphere to halt warming or at least slow its growth down.
I can almost guarantee that the response of the current US government would not be "Whew...now that we've averted the near term problems we were facing from climate change we can get to work on seriously getting rid of most fossil fuels use".
No, it would be "Great! We can now get rid of those cancer causing wind farms and ugly solar farms and go all in on a 100% fossil fuel economy featuring a massive increase in coal. We should have been doing that all along but enough people believed in the global warming hoax to slow us down. Now we are free of that!".
We'd need ongoing increasing SO₂ injections to counter this, and all it would take is something to disrupt that for a few years and then all that increasing warming that has held back by those injections would come roaring back. But we'd be getting that warming increase over a short term instead of a longer term, making it much harder to deal with.
The effects of deliberate small scale atmospheric aerosol injections is something I've studied extensively. The short term results are often quite noticeable even by parties not directly participating in the study.
This is why I think it will not be done. Any possible blow back will be attributed to those who actioned it, even if it might not be their fault. Do some injection in one part of the world and breadbasket crop fails 6 months later, they can point the finger even if it would have happened regardless.
I don't think one will be able to prove that you affected anything directly, so quite the opposite, there's no liability.
Otherwise I'm gonna hold the international maritime organisation solely responsible for every drought, fire and megastorm from how much their ban of fuel with sulphur content has exacerbated the warming situation by destabilizing the existing balance.
The red states have begun banning geoengineering and even small-scale tests. It seems to be spreading across these states, which suggests that we'll soon see similar laws being proposed at the Federal level.
I don't see this as a truly organic reaction. When I see the same laws popping up in multiple states, my suspicion is that it's driven centrally by right-wing think tanks, probably to benefit the fossil fuel lobbies. You don't need aerosol injection if there's no climate change, so we need to make it illegal (just as we need to defund Earth sciences, fire climate scientists, etc.) Similarly, if we need aerosol injection, then climate change is real. It's all one big package.
I think is pretty reasonable for people to be suspicious of spraying aerosols into the atmosphere. What's the effect of breathing this stuff in long term? Can you even construct an effective experiment around here? Do you know what the second and third order effects are?
It wasn't too long ago since another aerosol punctured a giant hole into our ozone, what was the effect of that?
The irony is that this is probably true, but the greater project of suppressing any acknowledgement of climate change exceeds the possible benefits that aerosol injection might afford even to GHG emitters. It’s actually pretty goddamn frightening because it means these people are ready to take the whole damn ship down around them.
ETA: Don’t get me started on how weird it is that there’s a pre-spun conspiracy theory in chemtrails, one that makes zero sense but happens to align perfectly with making geoengineering even more difficult. But now I’m being conspiratorial.
The strategy still seems pretty bad to me. Even if fossil fuel lobbies convince MAGA-types in America that there's no climate change, other countries may do their own geonengineering. Nothing prevents areas like China and EU from starting their own programs, and thanks to more successful education systems their populations mostly don't have such anti-science sentiment.
Having the political system with the largest military on earth doing your bidding is a very good first step, if your goal is to make sure we do nothing while the whole world burns.
Countries are often gigantic though? There's plenty of state and local efforts going on in the United States despite the federal government currently backtracking for instance. Does that count as... worth burning tons of fossil fuels to bomb out of existence?
There's currently 31 states who have bills to ban geoengineering. Its not just red states, there are plenty of "blue states" on the list as well. Painting this as a partisan political issue is just stupid. California is set to join the list as well.
March 2025:
As of this week, 31 out of 50 U.S. states—well over half the nation—have introduced legislation to ban or severely limit geoengineering and weather modification operations. Just days ago, on March 24th, that number stood at 24. Seven new states have joined in under a week, reflecting an undeniable groundswell of public awareness and political will.
You “hate this political stuff” and then you link to a bizarre Substack where the first quote is from noted non-partisan scientist RFK Jr, and he’s claiming that because multiple states have introduced legislation that implies a groundswell of public opinion against evil geoengineering.
Anyone can introduce legislation. Keep this off HN.
A) Quotes from politicians don't discount the facts of the matter.
B) Had you spent five minutes researching what's going on, you would've seen an article from last year about Alameda City, a city in California (yes, THAT California, the supposed VERY BLUE STATE California) that banned geoengineering:
June 2024:
A Northern California city council voted early Wednesday morning to cancel the nation’s first outdoor experiment into the potential to limit global warming by altering cloud behavior.
The five-member Alameda City Council voted unanimously to reject University of Washington researchers’ aerial spraying of liquefied salt from the deck of a retired aircraft carrier in San Francisco Bay, two months after the experiment began.
And shockingly, the report isn't in some strange substack. Its actually a well known LEFT LEANING site - Politico:
Entirely different forcing mechanism(s). The two most promising vectors are stratospheric injection and marine stratocumulus injection. Both approaches induce very different radiative and attendant circulation responses, and aren't relevant in the context of this work.
The calcium carbonate dust is reflective (the aim of the engineering is to reflect sunlight away from the Earth's atmosphere in the first place). However, it doesn't contribute to acid rain or oceans like the sulfate dioxide does (the aerosol that East Asian scrubbers are removing).
The CO2 (a greenhouse gas) amount isn't increased in this engineering effort. It increases because of burning fossil fuels, though. In the East Asian countries, they are producing/using more energy (via burning fossil fuels), but only removing the reflective aerosol; they're still emitting the CO2.
If cost was no object, we'd probably need to use the calcium carbonate immediately (to prevent the sunlight from entering the atmosphere immediately), we'd scrub existing carbon from the atmosphere (CO2), and we'd convert power plants to non-emissive technologies (and also install scrubbers onto existing ones for as long as they're needed).
Looking at the wiki, the effects of long term exposure to CO2 under 0.5% of partial pressure (5000 ppm) are not known. The current concentration is close to just 430 ppm (though that's more than enough for the greenhouse effect). What sort of mental decline do you suspect? And any references?
The short term effects are known though (bad indoor ventilation causes decreased intelligence due to increased CO2 concentration), and a permanent short term effect would arguably be a long term effect.
There have been a handful of studies that last time I looked all involved a single investigator that have shown decreased intelligence due to levels around 1000 ppm.
NASA and the US Navy have been conducting studies since the 1960s showing no loss of cognitive function up to 50000ppm or so.
Submarines and space vehicles regularly operate at CO2 levels much higher than 1000ppm. If the levels of cognitive decline were anywhere close to what some of these studies show it would be easily observable in astronauts and submariners.
Not to mention testing locations with good ventilation would show drastically higher scores over all on standardized tests, and individuals would show drastically higher scores between attempts depending on ventilation.
None of these things happen. The only logical conclusion is that there is some flaw in study methodology.
> Recent studies have shown that short-term exposure to high levels of indoor carbon dioxide (CO2) could negatively affect human cognitive performance, but the results are still controversial. In this study, a systematic review and meta-analysis of fifteen eligible studies was performed to quantify the effects of short-term CO2 exposure on cognitive task performance. The control CO2 levels used for comparison were below 1000 ppm, while the exposure concentrations were divided into three groups: 1000–1500 ppm, 1500–3000 ppm, and 3000–5000 ppm. The results indicated that CO2 exposure below 5000 ppm impacted human cognitive performance, with complex cognitive tasks being more significantly affected than simple tasks. The complex task performance declined significantly when exposed to additional CO2 concentrations of 1000–1500 ppm and 1500–3000 ppm, with pooled standardized mean differences (SMDs) (95% CI) of −2.044 (−2.620, −1.467) and −0.860 (−1.380, −0.340), respectively.
If you dig in you’ll find that for simple cognitive tasks they found no effect.
Then they analyzed only complex cognitive tasks. But fewer studies included complex cognitive tasks, and they used different methods of adjusting CO2 exposure (ventilation vs adding pure CO2)
Then you’ll note that of those studies they found that:
“The effects of pure CO2 on complex cognitive task performance decreased with increased CO2 concentrations”.
Between 1000-1500, and 1500-3000ppm they found a decrease in complex cognitive tasks performance, but at a higher exposure of 3000-5000ppm they found no effect.
This makes no sense until you read
“the complex cognitive task results under pure additional CO2 concentrations of 1000–1500 ppm and 1500–3000 ppm showed publication bias.”
Handful of studies (many with sketchy methodology—reducing ventilation, which brings with it many more variables than just increased CO2), publication bias, and a negative dose dependent response.
Also that Satish et al. study (the author is the one I was referring to in my last post—they also have several other studies on the subject) shows an enormous effect IIRC, which would skew the aggregate effects in the meta study.
The effect sizes in that study were the ones I was referencing when I said that such effects would be obvious.
I don't think that those objections are sufficient to draw a conclusion that quickly doubling the amount of waste product of our respiration in the air we are breathing in has no effect. Especially since people are not just briefly exposed to it but almost always suffer it from the first breath they take on this planet to the last. Without very strong evidence I wouldn't dare to assume that levels of this waste product that our species never experienced have no detrimental effect on our most vulnerable systems.
There are a ton of reasons not to want to increase atmospheric CO2, but I don’t think direct human health impact is something to worry about.
Since humans have been building shelter and living in caves, we have regularly been exposed to long term CO2 levels of 1000-2000ppm. The natural variations in ventilation dwarf a few hundred extra ppm in the atmosphere.
We’ve also been exposing submariners to thousands of ppm for extended periods with no observed effect, and we have many studies shows no observed effects up to 40k ppm.
We even have studies showing that small babies sleeping next to the mothers are exposed to CO2 levels of 5-10kppm.
