9 ms·

Cooling the Earth with a sunshade near the inner Lagrange point (2006)

• gl-prod 4y ago
  "It would make no sense to plan on building and replenishing ever larger space sunshades to counter continuing and increasing use of fossil fuel. The same massive level of technology innovation and financial investment needed for the sunshade could, if also applied to renewable energy, surely yield better and permanent solutions." - Roger Angel
  • GekkePrutser 4y ago
    That won't be necessary as fossil fuel is limited anyway. We're already past peak oil. Eventually we will have burned it all. But I agree it's a technological bridge too far. I could see it help to fix the damage already done (and the damage to be done before we can move to fully renewable) but I don't think it's realistic. But I don't think other mitigation methods like carbon capture are realistic either (not at a scale to actually matter).
    • adastra22 4y ago
      Peak oil is/was a myth. There is at least an order of magnitude more oil than we could ever burn without causing a runaway greenhouse effect. Peak oil as a concept only ever made sense if you assumed a static price of oil. There are immense reserves when the price per barrel rises, or when new technology like fracking opens up new reserves.
      • jabthedang 4y ago
  • adastra22 4y ago
    This is a terrible take. First of all, the price of space launch is plummeting, making the cost of launching a fleet of sun shades drop like a rock. It may soon be veeery affordable. Like, something Elon would do just for the kicks. Second, there are distinct advantages to higher CO2 levels in the atmosphere. It makes agriculture grow more quickly, leading to higher food yields. And the greenhouse effect is mostly independent of latitude so places like Siberia and northern Canada become habitable while the tropics do not become so hot as to be unlivable. Raising the global temp by 2 degrees could double the amount of high quality arable land suitable for dense human habitation. Third, instead of a sunshade we could use a larger translucent film which blocks UV-B light like sunglasses. Imagine a world without skin cancer!
    • hoosieree 4y ago
      I'm not an expert but blocking UV-B may have some negative consequences.
      • uoaei 4y ago
        Imagine a world where bees can't see the centers of flowers.
        • adastra22 4y ago
          Bees see with UV-A light, not UV-B.
          • uoaei 4y ago
            Bees see with both. UV-A (320-350nm) and UV-B (290-320nm) both overlap with bee visual spectrum (300-650nm). Do you have data on which flowers in which geographical areas reflect with UV-A and/or UV-B? Maybe to bolster your argument you will need to prove that this won't affect bees, and pollinators more generally.
            • adastra22 4y ago
              The harmful UV-B rays are under 300nm, and that’s the cutoff for bee vision for the same basic biological reason. Below that limit is what you’d want to filter out.
      • adastra22 4y ago
        It does not. UV-B is ionizing radiation and is incapable of being used by biological processes as a source of energy. About the only effect it has on our biome is that it contributes to the production of ozone, and it is possible that filtering out UV-B might reduce (but not eliminate) the ozone layer. However the main/only benefit of the ozone layer is to filter out UV radiation, so... UV-B is like mosquitos, one of those rare things that really only does cause harm and can be safely eliminated if possible.
    • deleted 4y ago
  • jollyllama 4y ago
    Easier from a perspective of organization and governance, too. Energy policy can be managed with existing institutions. If you want to launch a megafleet to block the sun, who they hell do you ask for approval? The UN? How many countries do you need to sign off on it?
    • marcosdumay 4y ago
      If the "you" here is not the all powerful US, it's a certainty that there will be a war over the project. If it's the US, it will "just" lose a lot of soft-power.
      • dylan604 4y ago
        What if it's not even the US but some private company with launch capabilities that also may or may not be US based?
        • DocTomoe 4y ago
          Friendly reminder that a private company with launch capability currently is massively increasing the space junk problem and about to trigger the Kessler scenario for a quick buck and internet access without cables, while at the same time ruining surface-based astronomy. So why stop there? And as always, the Simpsons have predicted it: https://www.youtube.com/watch?v=L3LbxDZRgA4 https://www.youtube.com/watch?v=L3LbxDZRgA4
          • marcosdumay 4y ago
            Well, just to keep in mind, internet access without cables is very valuable, and possibly the most valuable use of that space we can have. It's important to control the space junk problem, of course. But not at the cost of not using the space.
          • robbomacrae 4y ago
            I'm no Musk fan but is this true? I thought Starlink was low altitude so everything would fall back down pretty quickly. And while I imagine its not great for astronomy surely it's not much work for some institution or enterprising individual to create a tool for using the known position and timing of such satellites to help remove their impact on images?
  • mc32 4y ago
    One needs it only long enough to tide us (humanity) over till we have viable alternative shoe-in solutions. Without that, turning on a dime away from hydrocarbons toward renewables only will inflict lots of damage to progress and people in both rich and poor countries as well. We need an intermediate solution to attenuate the impact of hydrocarbons while we transition to alternative energy sources gracefully. Lots people who advocate for the "bandage tear-off" fix are those who envision being able to withstand the consequences of such a choice. (Oh, I'll telecommute, I'll take the train, I'll get geothermal, I'll move to a mild climate, etc.) Most people don't have the above choices.
  • knappe 4y ago
    This also puts all of our eggs in one basket. That would seem to be a troublesome thing to do.
  • boxed 4y ago
    That's true. Except the little detail of time. We've already passed the time when that rational and sane option was viable. Now we're in a situation where we need both.
• greggeter 4y ago
• deleted 4y ago
  [deleted]
• dbrueck 4y ago
  I'd love to see a sci-fi writer use this as a premise and explore the unintended consequences. Or maybe a story about this where there was a seemingly minor miscalculation somewhere or some overlooked factor that ended up being catastrophic.
  • standyro 4y ago
    There has to be a book or two that explores this! The closest thing I can recall is the Animatrix/Matrix series exploring the concept of blotting the sun out with some sort of artificial clouds.
  • CM30 4y ago
    I recall Snowpiercer had a similar premise, or at least the animated prequel thing did. They tried to reverse global warming by using some sort of aerosol substance to block sunlight, and ended up casting the Earth into a massive ice age instead.
    • dbrueck 4y ago
      Thank you, I'll check it out!
  • Cyberdog 4y ago
    Ever seen the movie Snowpiercer? It was based on a comic called Le Transperceneige and they also more recently made a TV series about it, but I've only seen the movie and highly recommend it. It takes place on an Earth stuck in a planet-wide heavy winter due to an anti-global-warming scheme gone wrong. It's the first thing I think of whenever I hear of space umbrellas or these sorts of anti-warming ideas. EDIT: Ah, someone sniped me.
  • biomcgary 4y ago
    The nice thing about using the L1 Lagrange point is that it is unstable, so eventually the sunshades will disperse. Even with station keeping, the satellites will eventually break.
  • boxed 4y ago
• at_a_remove 4y ago
  I'm not a game theorist or an economist, but I believe that dealing with climate change will involve, uh, "non-cooperative solutions." People saying, "If we can all just get together and ..." keep forgetting we can't even get humanity to stop stabbing each other in the face. If the "solution" depends on mass cooperation, and worse yet, cooperative mass sacrifice, I just don't think it will happen. Therefore, we need to look at solutions that don't require eighty percent of humanity agreeing on something.
  • wmf 4y ago
    Check out Neal Stephenson's Termination Shock. In fiction you can consider things that are too taboo to discuss seriously.
  • CM30 4y ago
    Yeah. Which is why things like this (limiting sunlight so greenhouse effects are mitigated) mixed with a push to 100% clean energy and carbon capture (both via trees and technology) are probably the way forward. You might get away with pushing to limit non reusable resources if companies were the targeted party though (so instead of asking people to recycle or reuse, governments outright demaded corporations stop providing as much disposable packaging).
    • candiodari 4y ago
      And what happens when one realizes that limiting sunlight, of course, is an incredible weapon against your adversaries. Or, god forbid, ampliflying sunlight? And then, when the inevitable happens and it moves from theory to "you know ... actually ... our atellite could actually do that" and then to actually doing it against that really-evil-dude-that-totally-deserves-it du jour? Or we do it first to lessen the economic impact of a cold not-very-well-oiled winter in Europe? Plus, I'd like to point out that even when it goes perfectly smoothly, ironically, fixing climate change will make many climate change effects worse. For instance, currently meltwater is helping offset the draught in California (and in the nearly-1-billion-people Indus valley, and a hundred less important valleys). If we slow down climate change that meltwater contribution stops, today, almost entirely. The same with many other effects. For instance the greening of the Sahara will stop, we will not only see less extreme weather, but less rainfall ... everywhere. And that will do a lot to prevent the countries from growing.
• jeffjobs4000 4y ago
  Geoengineering projects should be getting far more attention in the public eye. There are serious alternatives to letting society crumble due to climate change. People are choosing not to have children and citing climate anxiety as the reason. Just today, two teenagers in London ruined a Van Gogh for a climate protest. It's absurd. If you apply any amount of rational thinking to the problem, you'll realize that it's incredibly likely that we'll solve climate change. The paper cited here is from a U of Arizona professor who previously won a MacArthur "genius" grant, and develops the optics for some of the largest telescopes in the world. Not a quack. Harvard has a Geoenigineering department. Smart and credible people are working this problem out. We should give them our attention, money, and talents. The paper in this post lays out a plan to reduce climate change for under 0.5% of world GDP in 2006. The price of launching weight into space has plummeted in the 15 years since this paper was written. If you're worried about unintended consequences of geoengineering, then contribute to reducing risk by helping to develop AI. Then we'll be better able to model its effects and mitigate risk through increasingly accurate simulation. We need to tell people to study materials science or something that will actually help if they're concerned about the climate. Climate Fatalism is so mid.
  • soulofmischief 4y ago
    > ruined a Van Gogh Ok, I'll bite. Let's read up on this claim. https://www.npr.org/2022/10/14/1129098184/van-gogh-sunflowers-soup-climate-protest-london-gallery https://www.npr.org/2022/10/14/1129098184/van-gogh-sunflower... > Climate protesters threw soup over Vincent van Gogh's "Sunflowers" in London's National Gallery on Friday to protest fossil fuel extraction, but caused no discernible damage to the glass-covered painting
    • jeffjobs4000 4y ago
      Well that's good news. Thanks for correcting me. I think the attempt still makes my point that people are doing drastic things because of the prevailing narrative on the subject. I also don't mean to rag on the kids, I appreciate their passion. I just think it's misguided, and that if the wider array of potential solutions were better known then people could be more productive working on solving the problem. I think the fatalism about the topic is sad and unnecessary. I didn't mean the comment to be a cultural war "pick a side" post. The passion around the subject is justified, but I think it could be channeled more productively. Many people use to agree with Malthus in the 1800s that the world was about to run out of food. Then the Haber-Bosch process was discovered, and problem solved. More mental energy should be put into finding a similar solution for climate change versus this century's equivalent of "the world needs less people because of food limitations".
• Buttons840 4y ago
  I'm not sure that's a good idea, but it does remind me... One thing I remember about a solar eclipse I saw was once it began, and a tiny corner of the sun was covered, all the heat from the sunshine seemed gone. We were in the middle of a hot field under some trailer awnings. It was miserable in the sun until just 1% of the sun was covered, and then the sunshine was barely different than the shade. There was no visual difference in the sun, but you could feel the change in radiant heat.
  • klabb3 4y ago
    > until just 1% of the sun was covered Was this confirmed? It's easy to underestimate because the sun is so incredibly bright that it bleeds outside and maintains it's perceived intensity and radius much more so than the actual numbers, due to various optical phenomena. For instance, our eyes have logarithmic intensity response curve, so a 2x increase feels more like – say – a 1.1x increase.
    • Buttons840 4y ago
      No, it's a subjective estimate. Everything I said is subjective. I did look at the sun with glasses that made it appear as a dim orange ball, and as soon as the moon barely started to cover an edge it was comfortable to walk around in the sunshine. By totality we were all wearing jackets. This was in Idaho.
• cs702 4y ago
  If the stakes weren't so important, this tidbit from the abstract would be really funny: > The concept builds on existing technologies. It seems feasible that it could be developed and deployed in ≈25 years at a cost of a few trillion dollars, <0.5% of world gross domestic product (GDP) over that time.
• mysterydip 4y ago
  How much energy would have to be absorbed/refracted in order to make a difference, and what material can withstand that much energy continuously without melting?
• seydor 4y ago
  Cooling tech is like a shit-test for climate change absolutists. If one truly believes the models and premises that the observed climate change is antrhopogenic and catastrophic then there should be almost no objections to cooling tech, unless the models predict that cooling the earth would be worse
  • mrtnmcc 4y ago
    In control theory, something can be observable without being controllable
  • splitstud 4y ago
  • immmmmm 4y ago
    You apparently didn't heard about ocean acidification nor the fact that the latter provide half the oxygen you and I breath. Oh sorry, i forgot we can techno-fix that with iron-seeding and massive alcali dumps. So to make it short: these "solutions" provide FF companies more arguments to pump more oil. BTW we are already MASSIVELY reducing forcing (0.8W/m2) with sulfur aerosols from sea shipping. When that goes down expect even faster heating, with consequences beyond what the bleakest models predict. I leave you the size of the sun shade to get that negative forcing as an exercise.
  • klabb3 4y ago
    No it isn't. There is a night and day difference between finding a causal link between X and Y, and controlling Y with a new method Z. It's orders of magnitude more complex and it took decades for consensus on only the causal link, and the predictions vary tremendously. Our prediction power on complex systems is extremely limited. If you take medicine as an example, all drug development comes with unpredictable side effects. The process for putting the safe label on a drug is through testing it on 10s of thousands of people – it's extremely primitive and only works if we're willing to accept catastrophic failures from time to time. Even when something goes wrong, we often don't know why. And even when we know why, Pharma companies have so much invested that they often hide it for profit reasons. Or: When we started producing CFCs we had no idea that we'd weaken the ozone layer. How could we? It's a miracle that the causal link was found at all. The problem of having only one planet makes climate engineering extremely risky. Obviously it depends on what method is used. Carbon capture is ~easy to test for side effects in isolation, whereas chemicals in the stratosphere or a space sunshade is harder.
• GolfPopper 4y ago
  I fully expect Musk (or someone trying for the same niche) to be actively pitching geoengineering and/or near-Earth megaprojects in response to climate change by the end of the decade.