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Earth Space

Could We Fight Global Warming With A Giant Umbrella in Outer Space? (seattletimes.com) 194

The New York Times reports on a potential fix for global warming being proiposed by "a small but growing number of astronomers and physicists... the equivalent of a giant beach umbrella, floating in outer space. " The idea is to create a huge sunshade and send it to a far away point between the Earth and the sun to block a small but crucial amount of solar radiation, enough to counter global warming. Scientists have calculated that if just shy of 2% of the sun's radiation is blocked, that would be enough to cool the planet by 1.5 degrees Celsius, or 2.7 Fahrenheit, and keep Earth within manageable climate boundaries. The idea has been at the outer fringes of conversations about climate solutions for years. But as the climate crisis worsens, interest in sun shields has been gaining momentum, with more researchers offering up variations. There's even a foundation dedicated to promoting solar shields.

A recent study led by the University of Utah explored scattering dust deep into space, while a team at the Massachusetts Institute of Technology is looking into creating a shield made of "space bubbles." Last summer, Istvan Szapudi, an astronomer at the Institute for Astronomy at the University of Hawaii, published a paper that suggested tethering a big solar shield to a repurposed asteroid. Now scientists led by Yoram Rozen, a physics professor and the director of the Asher Space Research Institute at Technion-Israel Institute of Technology, say they are ready to build a prototype shade to show that the idea will work.

To block the necessary amount of solar radiation, the shade would have to be about 1 million square miles, roughly the size of Argentina, Rozen said. A shade that big would weigh at least 2.5 million tons — too heavy to launch into space, he said. So, the project would have to involve a series of smaller shades. They would not completely block the sun's light but rather cast slightly diffused shade onto Earth, he said. Rozen said his team was ready to design a prototype shade of 100 square feet and is seeking between $10 million and $20 million to fund the demonstration. "We can show the world, 'Look, there is a working solution, take it, increase it to the necessary size," he said...

Rozen said the team was still in the predesign phase but could launch a prototype within three years after securing funds. He estimated that a full-size version would cost trillions (a tab "for the world to pick up, not a single country," he said) but reduce the Earth's temperature by 1.5 Celsius within two years. "We at the Technion are not going to save the planet," Rozen said. "But we're going to show that it can be done."

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Could We Fight Global Warming With A Giant Umbrella in Outer Space?

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  • by Black Parrot ( 19622 ) on Saturday February 03, 2024 @11:38AM (#64210580)

    except cutting back on emissions.

    • except cutting back on emissions.

      While we must do that, it's too late for a lot of the damage. That CO2 in the atmosphere isn't going anywhere for a long time, and the so called CO2 removal proposals will almost certainly make things worse.

      • ...and the so called CO2 removal proposals will almost certainly make things worse.

        So you're just going to reject all of them out of hand without even bothering to examine them?
        • Currently the main use of CO2 capture seems to be "Hehe see we don't need to do anything, other people later on can pay to fix it."

        • ...and the so called CO2 removal proposals will almost certainly make things worse. So you're just going to reject all of them out of hand without even bothering to examine them?

          Where did you get the idea I rejected them out of hand?

          Aerosol injection will create acid rain, which doing it on a global scale with kill and likely extinct many land animals, destroy buildings and forests, and make for really negative health effects on the rest of humanity. When the rivers drop their acid load into the ocean, it will alter the ecosystem starting with the littorals, eventually sulfurizing the oceans, and will make many shellfish extinct, have a strong effect on Krill and the species th

    • except cutting back on emissions.

      I agree with your sentiment. That said, even if we got greenhouse gas emissions down to zero by tomorrow morning, we'd still need some serious mitigation strategies. Reducing incoming IR radiation would be a good tool to have - along with carbon sequestration, if that ever becomes practical at scale.

      That said, a million square miles worth of space-based parasols sounds horrendously impractical, even if you discount the possible conflicts with various other space activities.

    • This is particularly insightful since another /. post mentions 2% of US electricity generation goes to freakin' bitcoin mining. And I'm guessing that power isn't being generated by a tokamak or solar or any other 'nice' method.

      First principles. CO2 is generated as a result of human activities. Reduce the rate of human population growth and the problem . No, not talking about James Bond + Moonraker stuff. Just boring ideas like incentive based birth control. China proved it could be done, and aside f

    • You'd see boundless rage if this were proposed as a solution, ie actually paying for it to be done. This one is akin to "Just you wait, the developing nations will get richer and then have less children, all you have to do is let us burn all this coal without worrying about it, the solution to both global poverty and global warming is simply waiting."

      Hehe we could solve global warming like this, we of course won't it costs too much and worst case we can pay a few people to rile up the environmentalists to k

  • by Joe_Dragon ( 2206452 ) on Saturday February 03, 2024 @11:42AM (#64210584)

    and we need Nuclear power to make up for the loss of solar power

    • For the sake of argument, a "space umbrella" can be faceted to only cast shadows on empty spaces. Not that such a monstrous construct is a reasonable solution to anything.
      • How much of a monster ?  My scratchpad says  12 *10^6 cubic meters at a thickness of  4x  red light. That volume does not appear TOO monstrous.
      • They mean parasol, not umbrella. Umbrellas are for rain. I'm unaware of there being a space rain issue or have I missed something?
  • No. (Score:5, Insightful)

    by Mr. Dollar Ton ( 5495648 ) on Saturday February 03, 2024 @11:43AM (#64210586)

    We still have to grow food, and for that we need them photons as plants expect them.

    • Re: No. (Score:4, Insightful)

      by OrangeTide ( 124937 ) on Saturday February 03, 2024 @12:00PM (#64210624) Homepage Journal

      We don't really need as much as you think. Plants grow fine with clouds overhead.

      • You can discuss this with my tomatoes, who stubbornly insist on having sunlight in order to get red, ripe and tasty.

        • That's fine. You can use electric grow lights to get them red, ripe, & tasty. Then we'll need another solution for the increase in CO2 levels from grow lights generated from blue hydrogen while countries rush to build nuclear power stations that run decades behind schedule & cost $billions more than budgeted for.
        • Can your tomatoes really tell a 2% difference?

          https://physics.stackexchange.... [stackexchange.com].

        • by Calydor ( 739835 )

          The proposal isn't to cover the Earth in perpetual night like some dystopian fantasy novel. It's about very slightly lowering the amount of light that reaches the surface of the planet.

          Can YOU tell the difference in luminosity between a 100 watt bulb and a 98 watt bulb, especially without having them side by side to compare?

    • Re:No. (Score:5, Interesting)

      by burtosis ( 1124179 ) on Saturday February 03, 2024 @12:12PM (#64210648)

      We still have to grow food, and for that we need them photons as plants expect them.

      Not to mention I love how these studies neglect the massive amounts of fuel that needs to be burned to place small nation sized objects in the path of the sun and maintain them. 2% of 67 million square miles is still 1.25 million square miles. Even at about 4 times thinner than a sheet of average paper we are talking about lifting 0.1 cubic miles, and at a density of average plastic talking 42 trillion grams or 420 million kg / 1 billion pounds. Throw in 25lbs per pound to geostationary orbit and it’s 25 billion pounds of fuel and it’s about 4 months of all road traffic fuel for the US and at a cost of $10k/lb it’s $10 trillion or the cost of half a year of the US economy. And that’s just the launch cost. Throw in testing, design, material, and maintenance and we can easily double those figures.

      • Re:No. (Score:5, Insightful)

        by Mr. Dollar Ton ( 5495648 ) on Saturday February 03, 2024 @12:17PM (#64210658)

        Yep. Like someone said upthread, anything but lowering the emissions.

      • Yeah but "giant space umbrella" will solve all our problems. Rejoice!
        • Yeah but "giant space umbrella" will solve all our problems. Rejoice!

          No one is claiming that reducing insolation is a complete solution to the problem. It's a potential way to reduce the severity of the problem while we shift to technologies with lower carbon footprint.

      • I love how these studies neglect the massive amounts of fuel that needs to be burned to place small nation sized objects in the path of the sun and maintain them

        I don't think they are neglecting that fact. The fuel needn't be fossil in origin. They're not proposing to use non-fossil fuels for the tests, of course, but if the tests prove the idea feasible, the question of whether using fossil fuels to launch the rockets contributes more to warming than the shades reduce it would have to be considered, and using non-fossil fuels would be one of the options.

        SpaceX, for example, intends to shift to non-fossil methane at some point in the future of its Starship prog

  • by CrappySnackPlane ( 7852536 ) on Saturday February 03, 2024 @11:47AM (#64210594)

    Rozen said his team was ready to design a prototype shade of 100 square feet and is seeking between $10 million and $20 million to fund the demonstration. "We can show the world, 'Look, there is a working solution, take it, increase it to the necessary size," he said...

    Considering the whole issue with solar shields is being able to launch one of the necessary size into space, I'm not quite sure what the point of this prototype would be.

    Anyway, if any investors are reading, I'll be happy to provide an 8.5 x 11" prototype shade for merely $5 million. I could possibly even settle for $2.5 million.

    • Rozen said his team was ready to design a prototype shade of 100 square feet and is seeking between $10 million and $20 million to fund the demonstration. "We can show the world, 'Look, there is a working solution, take it, increase it to the necessary size," he said...

      Considering the whole issue with solar shields is being able to launch one of the necessary size into space, I'm not quite sure what the point of this prototype would be.

      Anyway, if any investors are reading, I'll be happy to provide an 8.5 x 11" prototype shade for merely $5 million. I could possibly even settle for $2.5 million.

      You aren’t just throwing shade are you?

    • I'll do a 17" x 22" for only $1 million. And only $500k each for another 7 of them if you pre-order now.

  • by e065c8515d206cb0e190 ( 1785896 ) on Saturday February 03, 2024 @11:53AM (#64210606)
    It's not like we need the sun for anything. What could possibly go wrong?
    • by skam240 ( 789197 )

      What could possibly go wrong?

      If it causes problems we can just get rid of it by breaking it up and have it burn up on a re-entry or bump it out into space. This is an incredibly low risk proposal.

      • Isn't such a drastic move that it might be too late when / "if it causes problems"?
        • by skam240 ( 789197 )

          What possible scenario are you predicting? As far as I can see In terms of its effects on the planet this is no different than some extra cloud cover.

          • by dbialac ( 320955 )
            And this kind of assumption is why we'll find a way to screw it up.
            • by skam240 ( 789197 )

              Nice pessimism. Care to explain yourself?

                • by skam240 ( 789197 )

                  Great sci-fi flick, absurd concern in this scenario. And I mean really, you're citing a movie whose solution to a freezing earth is a perpetually moving train. How does that make any sense?

                  As I said before, we can always remove the sun shield. Furthermore, the idea that such a limited shield could freeze the earth without us having a clue that it would happen ahead of time is crazy. We know a bit about how heat and energy work.

              • by dbialac ( 320955 )
                Netscape introduced cookies in the mid-90s. Pessimists said they could be used for nefarious tracking. Optimists thought, what could possibly go wrong?
          • I'm not predicting any scenario in particular. I'm just worried about possible unintended consequences when drastic action is taken (and that is true also for geo-engineering). Blocking the sun on a scale large enough to matter seems prone to intended consequences. But maybe that's just me.
  • by PJ6 ( 1151747 ) on Saturday February 03, 2024 @12:00PM (#64210622)
    We have a system that thwarts democracy and starves large sections of the population if people stop buying shit they don't need.

    This is exactly the opposite of how we need it to work.

    Nothing is going to get done until we talk economics.
  • Ocean acidification (Score:5, Informative)

    by C3ntaur ( 642283 ) <centaur@netmagPL ... minus physicist> on Saturday February 03, 2024 @12:03PM (#64210634) Journal
    Something that gets too little attention is what the added carbon [wikipedia.org] is doing to our oceans. And while a solar shade might lower the temperature on the planet, it won't do anything to slow, let alone reverse, the damage from lower pH in the oceans.
    • by skam240 ( 789197 )

      Good point, I wasnt thinking about that at all prior to reading your post.

      Still though, it could be useful for mitigating at least some of the damage while we work on the issue. Because of third world economic growth as a planet we're still seeing global warming emissions increase. I'd bet money we'll continue to see a global increase for the next decade at the minimum which means it's going to be a hell of a long time before we see CO2 drop to pre industrial levels as that will only start when we stop addi

  • by turp182 ( 1020263 ) on Saturday February 03, 2024 @12:14PM (#64210652) Journal

    The Police wrote about this back in 1983.

    There's a little black spot on the sun today
    It's the same old thing as yesterday
    There's a black hat caught in a high tree top
    There's a flag pole rag and the wind won't stop

  • by Kelxin ( 3417093 ) on Saturday February 03, 2024 @12:19PM (#64210664)
    Launching a PDF bigger than Germany towards the sun?
  • by cstacy ( 534252 ) on Saturday February 03, 2024 @12:27PM (#64210672)

    A giant umbrella? A better idea would be a giant vacuum cleaner, which could be used to hoover up all the excess greenhouse gasses.

  • No. (Score:4, Informative)

    by Ossifer ( 703813 ) on Saturday February 03, 2024 @12:35PM (#64210680)

    Next question.

  • The CO2 emissions required to launch 2.5 megatons of hardware into deep space will be enormous. I doubt that much fuel exists on Earth but let's think about the math.

    Let's do a back of the envelope calculation...

    The Falcon Heavy (FH) is probably the most efficient launch vehicle today. It can launch about 44,000 lb into a Mars transfer orbit. That's a fair approximation for a Lagrange point orbit.

    At FH scales, launching 250 megatons into deep space would require 114 million FH launches, expending 772 TRILLI

    • by HiThere ( 15173 )

      That's OK. Were we to seriously try this it would obviously need to be fabricated in space, probably from asteroidal materials. So you can scale back your launch requirements to something reasonable. OTOH, you've got to add in a lot of technical development and experimentation. The main benefit would be developing a space-based construction industry. (I'm NOT assuming that the project would work properly.)

  • by Z80a ( 971949 ) on Saturday February 03, 2024 @12:43PM (#64210692)

    But simpsons did it

  • by JBMcB ( 73720 ) on Saturday February 03, 2024 @12:49PM (#64210710)

    Would be a much cheaper solution.

    https://en.wikipedia.org/wiki/... [wikipedia.org]

    For a proof of concept, look at warming temperatures from the 1940s to the 1950s when we were pumping tons of the stuff into the air through coal plants. The warming trend actually reversed itself for a while, until they found it caused acid rain, so they installed scrubbers on coal fired power plants, then the warming trend resumed. To avoid the acid rain bit, you release it into the upper atmosphere where it won't get into the clouds.

    • Would be a much cheaper solution.

      Possibly. But sulfate particulates rain out on a time scale of about a year, while a well-designed orbit should last for hundreds of years.

      And the side effects of sulfur oxides being put in the atmosphere (and coming OUT of the atmosphere) by the megatons are very unknown.

      • by JBMcB ( 73720 )

        But sulfate particulates rain out on a time scale of about a year, while a well-designed orbit should last for hundreds of years.

        And the side effects of sulfur oxides being put in the atmosphere (and coming OUT of the atmosphere) by the megatons are very unknown.

        They rain out when released into the lower atmosphere. In the upper atmosphere/stratosphere, they can stay up for decades. This has been tracked when volcanoes launch this stuff that high. When it eventually makes it's way down, it raises the pH of rain slightly, depending on the concentrations. The effects of that are well known as it happens naturally with wildfires and volcanoes.

  • I suspect it is much cheaper and more practical to make clouds.

    Any of these solutions is controversial:
    https://www.theguardian.com/en... [theguardian.com]

    • I suspect it is more affordable and more practical to build nuclear fission power plants than put a sun shade into orbit.

      A sun shade may reduce global warming but nuclear power plants would reduce global warming while producing energy.

      Anything that could impact sunlight or clouds directly could be weaponized. I guess nuclear power can be weaponized but then so could any energy source. Does anyone think power from wind or sun could not be used to make explosives, toxic gases, biological weapons, or any of

  • Hence if feasible, some really big assholes will get it funded and build.

  • It's all this nonsensical green washing. If you haven't figured it out these ridiculous stories of nonsense like carbon capture and giant umbrellas and other Insanity are just they are being pushed by the oil industry to give a certain percentage of voters the impression that everything is under control and they don't need to make any changes to how we generate power or how we organize our cities. We finally reached the point where the effects of climate change are causing serious problems with the water cy
  • It does not resolve the issue, it masks one of the symptoms.

    CO2 increases make the oceans acidic and humans dumber. Seriously - elevated CO2 impairs human cognition, to a degree we should be able to notice within a few decades while indoors (human activity elevates CO2, in a closed environment that can only dilute with external air CO2 will always be higher than that external air source).

  • While cutting down on the amount of sunlight will certainly slow the warming of the planet, it will also diminish the light going to photosynthesis that we (mostly) depend on for food and cleaning the crud out of the air. So I guess we can get what we need from the corner quickee mart and don't need to worry about the crops and forests. But what if we change our minds? Or there are unacceptable forms of collateral damage? Once all this stuff is put between us and the sun, how do we clean it up if it was a m

  • Without a system to hold it in position, the solar wind will just drive it away. How do they propose to hold something (or a vast array of something) a million square miles in size in place in space? I don't think we have the technology or the resources to do this.
  • It would be far cheaper to put a radiator on earth. Radiation in the 8 to 14 um range pass straight out to space. So the whole radiator can be on ground.
    • Not completely transparent in that range, but pretty good.

      But thermodynamics doesn't allow you to radiate waste heat at any higher rate than the Stefan-Boltzmann equation allows. The best you can do is to increase the emissivity toward unity. But most of the Earth's surface is water, and water already has an emissivity in that range of IR that's very near unity. (Yep, that's right. You think of water as transparent, but in the thermal infrared, it's black.)

  • I mean, what kind of knuckle dragger still thinks plants need sunlight?

  • ....inbound in 5...4...3....2....1. With all these bright ideas and attempts at manipulating nature there's always an unforeseen negative consequence, a factor that affects the climate that they didn't know about or know it's importance until the meddling began by which point it's too late.
  • The only solution is to throw soup at priceless works of art.

  • Find a decent size rock orbiting the Sun, grab it, have your robot factory grind it to bits of a manageable size, and then compress/extrude them under pressure* to form thin sheets, blocking the light. It would endlessly poop out a ribbon of thin crushed rock/sand.

    Easy peasy. We've already accomplished more difficult tasks as a species, this should be something that's achievable.

    (Or we could just stop fucking up the planet, but a) it may be too late, and b) apparently we don't really want to do that or we w

  • Russia, Canada, Greenland, Norway, Iceland, Finland, Sweden, Mongolia etc might not be amused.

  • A shade that big would weigh at least 2.5 million tons — too heavy to launch into space, he said.

    Obviously, just launch the weaving machine into orbit with the thread trailing down to the spools on the ground and make it in space. And yes, I realize that you'll also have to launch a sewing machine too at some point... Problem solved. :-)

  • Do not waste time on coming up with stupid ideas which will backfire, too.
  • The main problem with this solutions is not the cost and is not the technical feasibility. It's the fact that from the moment it's implemented, every single blizzard, every cold wave, every hurricane even, will be YOUR fault. Every time somebody is freezing their feet, they will be thinking "And they have a frickin' giant umbrella giving us even LESS SUN!". So, nobody want to be that "they"

  • We will need an area of 1 million square miles but this guy will handle the hard part by creating a prototype umbrella with an aera of 100 square feet. Then all we need to do is scale it up a bit

Waste not, get your budget cut next year.

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