Slashdot stories can be listened to in audio form via an RSS feed, as read by our own robotic overlord.

 



Forgot your password?
typodupeerror

A Sunshade In Space To Combat Global Warming 496

Posted by kdawson
from the thinking-big dept.
ultracool writes, "While the only permanent solution for human-driven global warming is developing renewable energy, a temporary hack to counteract possible abrupt climate change is to build a giant sunshade in space. The sunshade would be launched in small pieces by electromagnetic launchers, conventional chemical rockets being far too expensive. The sunshade could be developed and deployed in 25 years, would last about 50 years, and would reduce the amount of sunlight reaching Earth by 2% — enough to balance heating due to a doubling of carbon dioxide in the atmosphere." From the article: "The [trillions of] spacecraft would form a long, cylindrical cloud with a diameter about half that of Earth, and about 10 times longer... Sunlight passing through the 60,000-mile length of the cloud, pointing lengthwise between the Earth and the sun [at L-1], would be diverted away from our planet... The sunshade could be deployed by a total 20 electromagnetic launchers [collectively] launching a stack of [a million] fliers every 5 minutes for 10 years."
This discussion has been archived. No new comments can be posted.

A Sunshade In Space To Combat Global Warming

Comments Filter:
  • by Anonymous Coward on Monday November 06, 2006 @04:36AM (#16732823)
    I wonder what else this would stuff up? Less light for photosynthesis for example.
    • But if they're going to do it, then why not make it photovoltaic and get some energy out of it.

      Blocking/decreasing photosynthesis would be bad, since it's one of only ways to decrease the amount of CO2 in the atmosphere.

      We need to plant more trees to replace the devastation going on in South America, limit our CO2 production. America would be smart and try to help polish it's now tarnished reputation by taking a lead in this, and start by decreasing the amount of SUVs on the road.
      • Re: (Score:2, Funny)

        "But if they're going to do it, then why not make it photovoltaic and get some energy out of it."

        They would either have to invent a way to transmit power wirelessly, or make the world's longest extension cord.
        • by RsG (809189)

          They would either have to invent a way to transmit power wirelessly

          Power transmission in space via microwave is an old concept, been around since at least the 80s. You have a beam emitter on your power generating satellite, and a receiver station on the ground. The losses in transmission from orbit to ground are offset by the lack of atmospheric interference at the generating satellite. In space, there are no cloudy days, and no kilometers of air filtering your sunlight. It's like a hydroelectric dam, b

  • Or.. (Score:2, Insightful)

    We could just cut down on our insane energy usage/wastage.
    But hey, that would involve personal effort and we can't have that, can we.
    • Re: (Score:2, Insightful)

      by JoBlo69 (1023365)
      The history of the planet has shown that there is a history of global temperature change. How is this any different? I can see how people could think that we are polluting the planet (we are dont get me wrong) but do you guys really think that 'man' is actually doing enough harm to this planet?? Im not saying that this article is nuts or something all im saying is that i think there should be more research into our contribution to raising the earths temperature before we start making it colder without knowi
      • Re: (Score:2, Informative)

        by gomiam (587421)
        As you state, there have been global temperature changes before. But never at this rate. It is statistically reasonable to think that this is not just a coincidence. It might even be that global temperature was changing on its own to begin with, but the high rate probably means we are speeding it up.

        About doing "enough harm", I would be worried after seeing what be managed with just a few years of CFCs. Unfortunately, the "more research is needed" line would be good... if there wasn't s

      • Re: (Score:3, Informative)

        by Capt'n Hector (650760)
        Welcome to /. I don't mean to be rude, but when you say "i think there should be more research into our contribution to raising the earths temperature", are you speaking from the perspective of someone in academia, preferably in a similar field, or are you just another bloke? Because I do know a few people doing climate research, and there in fact has been considerable investigation into this matter. And it's not controversial, either. Inside these circles, they're pretty much in agreement that humans a
      • Natural or anthropogenic, the climate is changing. I would think that if the cause were natural, this would be even more necessary because we wouldn't really be able to do anything reasonable (like cutting CO2 emissions) to stop global warming. We also have ways of inducing global dimming terrestrially that we may wish to explore. If we end up in a positive feedback loop, something like this may be one of the only ways to break it. ...But my bet's that global warming is primarily an anthropogenic problem. T
      • by mcvos (645701)
        The history of the planet has shown that there is a history of global temperature change. How is this any different?

        The difference is that I'm living here now. Big extinction events in the past are all fine and dandy, but a big extinction event in the near future is suddenly a lot more personal. And if it's not me being theatened, it's my children or grandchildren (assuming I'll ever procreate -- no signs of that so far).

        I can see how people could think that we are polluting the planet (we are dont ge

      • Stolen from myself:

        Don't get me wrong. I'm not saying that global warming is not happening. I'm saying that I don't know. If I did know, there wouldn't be a damn thing I could do about it and certainly nothing at all that I should do.

        You see, about 10,000 years ago, the world was very cold. Today, we call it the "ICE AGE" (Austin Powers Finger-Quotes here). It was much colder during this "ICE AGE" than it is today. However, sometime between now and then, the earth warmed up and the "ICE AGE" ended. So if we
        • you're an idiot.

          learn something about what you're talking about or shut the fuck up.

          the opinion on global warming of someone who doesn't even know the definitions of "weather" and "climate" (Austin...) is not just worthless, but actually causes a noticable drop in your country's GDP.
      • Re: (Score:3, Insightful)

        by syphax (189065)
        Hi, welcome to slashdot.

        I love this logic:

        1. The climate has always been variable.
        2. Therefore, man is not having an impact on today's climate!

        QED, right?

        Here's an exercise: Explain to me how increased levels of CO2 (which are rising due to humans- I challenge you to find an explanation that has not been debunked from here to Shanghai and back), which Arrhenius demonstrated over 100 years ago [nasa.gov] could cause climate change, can't possibly be causing climate change?

        Hey, climate science is uncertain, and question
        • Re: (Score:3, Interesting)

          The solution is a bit nuts. But it could have an undo button. If each of these little craft opened up some sort of large, deployable shade, then when we decided it was a bad idea, we could simply have them fold back up.

          Also, replace the shades with solar panels, and you'd have a huge electric grid that could be used for extraterrestrial mining and ore refinement. Of course, then you have to steer asteroids towards Earth to run them through the process, which sounds like another screwed up idea.

          We should
    • by Jartan (219704)
      Perhaps the irony of whining about energy usage/wastage while running a nice fat energy sucking CPU to post on slashdot hadn't occured to you eh?
      • Re: (Score:3, Funny)

        by Anubis350 (772791)
        te be fair, how do you know the GP wasnt posting using lynx on his toaster, watch, llama or something? I mean, it *is* slashdot...
      • According to the meter on my plug, this home brew 486 PC is currently pulling about 35w. Sure, could be less but it could be a *lot* more.
    • by Cecil (37810)
      In an immediate sense I agree with you. But in the long run, it seems rather silly to hobble ourselves. The problem with energy usage, and even wastage, is not because we're using energy, but because of where that energy comes from (hydrocarbons).

      If our energy came entirely from solar energy, we could use almost any amount of energy we wish (within reason) with negligible detrimental effects.
      • by doom (14564)
        If our energy came entirely from solar energy, we could use almost any amount of energy we wish (within reason) with negligible detrimental effects.

        Ditto for nuclear energy, but then we'd all be going to hell.

    • Also interesting to note I got modded -1 over-rated for this opinion. One wonders if there is a mod who drives an SUV and sporting a twin GFX card monster PC muttering about how no commie liberal is going to stop him doing what he damn well pleases and FU with some negative mods.
      • "...a mod who drives an SUV and sporting a twin GFX card monster PC muttering about how no commie liberal...

        More likely he's the mod with 187 trillion AOL cd's, muttering about how NASA are going to launch them to build this thing. Seriously though, this has been on /. before, it's a crackpot idea stolen from a simpsons episode, nothing has changed 'cept it's a bit older and less funny the second time around.
    • by Jessta (666101)
      I don't think much is going to be widely done about global warming at least for the next 30 years or so. At which point we'll be experiencing a lot of the effects, which I'm hoping will motivate people.
      But, the green house gases have been building up for a long time. Even if we reduced our current green house gas emissions, how long would it take for the build up to dissipate?

      This idea might be useful if this is going to be a problem.
  • At least they're not using a giant space mirror. A project like that could possibly be retrofitted into a giant space laser and used to destroy all the robots on the planet only to be narrowly avoided by moving the planet away from the sun, legthening our year by a week. I know at the very least Al Gore would be against such an action.
    • it would target him too! :)
    • Actually, in one of Arthur Clarke's "Oddysey" novels (I think it was "3001: Final Oddysey") they mention using space mirrors sometime during the 21st century to combat global warming. This would mean that yet another insight of Clarke's would come true (after that of the telecommunication satellites).
  • Band aid fix? (Score:3, Insightful)

    by Alioth (221270) <no@spam> on Monday November 06, 2006 @04:40AM (#16732857) Journal
    The trouble is with things like that are the unintended consequences that it'll undoubtedly have. The real fix is that we start living sustainably. The sunshade won't fix problems such as that which will be caused because we're using 4 barrels of oil for every new one discovered.
    • As I quite literally just posted in Snowball Earth Hypothesis thread only this time maybe in a bit more detail...

      So if you support the idea of global warming and that humanity is by far the largest contributor to the phenomenon then you believe that through our own naive actions we have potentially created a dire set of consequences for humanity and many other species on Earth. Now you want to actively cool the Earth by changing it's albedo even though we are still ignorant to how the climate actually work
      • We are apart of nature, anything we do is natural. If we kill ourselves by destroying the environment then it's no different than if a pack of wolves starve to death because they hunted their food to extinction.

        With all due respect to our lupine friends, it's different to me. Also, like it or not, we are above nature. We are operating on a fundamentally different moral level to the rest of known nature because we can foresee the consequences of our actions to a certain degree, or at least we can know that t

    • ``The real fix is that we start living sustainably.''

      Yes. And biofuel is a good start. As I've said [slashdot.org] before [slashdot.org], biofuel is carbon-neutral, cheap to produce, does not create a dependency on foreign countries, and we can produce enough of it to power the whole USA using just a fraction of all the desert land there. It probably also doesn't produce as much nuclear waste as nuclear fission does (but I don't have any data for that).
    • ... the Nautilus Pirates hold the UN presidency at the moment, and they always veto any proposals to Launch Solar Shade. You'd think they wanted the sea levels to rise dramatically...
    • by sniepre (517796)
      I don't think I am the only one here that thinks...

      This is very, very scary.

      Yes, global warming may or may not be a problem. Yes, I know that ice is melting. Yes, I know that SUVs pollute.

      But seriously, when has playing God ever worked for mankind? To try to directly alter the climate of earth in a one-step non-retractable manner just seems like.. say.. solving world hunger by creating genetically altered corn that grows in sand with almost no water. It sounds good, that's not how it's meant to be.

      I don't k
    • by xtal (49134)
      [quote]
      The real fix is that we start living sustainably.
      [/quote]

      Very few people who say this actually understand what the implications of that statement are.
  • Cause and effect (Score:3, Interesting)

    by Antony-Kyre (807195) on Monday November 06, 2006 @04:46AM (#16732887)
    Various means of producing power causes pollution.
    Pollution = Greenhouse gases.
    Greenhouse gases cause global warming.
    Humankind puts up giant sunshade.
    Earth gets less light.
    Less light means solar power becomes obsolete.
    People need to burn more fossil fuels to get more power.
    Global warming picks up.
    Humankind builds a bigger sunshade.

    Okay, that is a big exaggerated, but my point is that we need to invest in solar power and stop using fossil fuels which are just so obsolete. Maybe we should work on fission.

    I don't care if I get modded down for this. I want to bring up this subject to discuss intelligently when I have time to reply.
    • by Gothmolly (148874)
      "I don't care if I get modded down for this" is a sure indication of a troll.

      For added trollerization, the line ... "I want to bring up this subject to discuss intelligently". Dude, this is SLASHDOT.
  • Might be just as difficult, but at least it is something people can understand.
  • If we used that 2% of solar energy as a substitute for fossil fuels, we wouldn't need any fossil fuels anymore.
    • Of course, but it isn't contradictory.
      We already receive far more solar energy that what we use from any energy source, and the only hard part about solar power is to produce the pannels in a way that is neither too expensive nor too poluting.
  • This is clearly a dumb idea, but its wrapped up in a way that will make sense to dumb people in power: Can't stand the heat? Get in to the shade!

    But along similar lines I was thinking about using hydrogen for fuel. There is a serious by product of creating hydrogen from oceans: oxygen. Oxygen is poisonous in high concentrations, but perhaps more worryingly its also a catalyst for fire. Isn't there a real chance that creating that much oxygen and pumping it into the atmosphere is going to take us from the re
    • by init100 (915886)

      Isn't there a real chance that creating that much oxygen and pumping it into the atmosphere is going to take us from the relatively safe 2.5% up to the scary-fireball-of-death 3% oxygen levels?

      I don't know where you got your numbers from, but they are incorrect by a large margin. The earth's atmosphere contains 21% oxygen, 78% nitrogen and about 1% other gases.

      Besides, I don't buy your "fireball of death" scenario. First, oxxygen will be used to burn the hydrogen produced (either literally in combusti

  • A launch every 5 minutes for how 25 years? Do you kow how much energy that will use?
    Where are they going to get it from? Oil so it creates more emmissions? Sun maybe, nope sorry we'll be blocking that too!

    The trillions this would potentially cost would be better served as investments in renewable energies.
    How about some long term solutions rather than band-aids?
  • Carbon Dioxide + Water + Light energy Glucose + Oxygen + Water

    Isn't there a way we can do this on a massive scale and remove carbon dioxide from the atmosphere? And I don't mean plant forests because that isn't likely to happen due to the space they require. Synthesize our own chlorophyll and do it much more efficiently than plants can? Or perhaps skip chlorophyll altogether and go with some other means of using light (or even use nuclear power if some other energy source would be more efficient) to implem
    • Isn't there a way we can do this on a massive scale and remove carbon dioxide from the atmosphere?

      And die from the sugar shock instead? :)

      On a more serious note, there is a way to store CO2. Currently, a lot of old creatures are storing it way below the earth crust. We call it oil and coal.

      If you look down the climate history of our planet, you'll see that we had COx levels way above the current, up to about 5% (nothing you'd enjoy living in... at least not for long). Since COx tends to be "heavy" (at least
  • Picture (Score:3, Funny)

    by nmg196 (184961) * on Monday November 06, 2006 @06:07AM (#16733275)
    Looking at the picture in the article, it looks like they're planning to put 100 millions CDs in orbit to reflect the light.
    If so, I think I have enough AOL CDs in my drawer for the mission to go ahead right now.
  • It would be way easier to modify earth's albedo instead.

    Man has modified albedo in two directions: polar caps are shrinking, decreasing albedo, and forest is shrinking also, increasing albedo.

    But by actively modifying the albedo of part of the sahara and the other big deserts, for example, you could feasibly dump into space the few percent required to equilibrate earth's climate.

    A combination of controled deforestation with desert "painting" could also do the trick.

    All this seems far more plausible than sun
  • by olman (127310)
    At least this shows that anyone who considers burning trees as a good source of energy (Hint! Renevable!) cannot handle advanced physics concepts like light pressure.

    Guess there's no limit to imagination when it comes to thinking of alternatives to building more nuke plants to replace coal/oil.
  • ...of Global Salvationism [livjm.ac.uk]

    Before we go do a really stupid thing and imperil everyone on the planet, perhaps we should do a little checking [climateaudit.org]? Just to make sure that we haven't been misled?
  • Er, Um, it won;t work at all:
    • Electromagnetic launchers have to accelerate the sails to escape velocity, nearly 25,000 MPH. The drag on an object goes up as the square of the velocity. Try calculating how much energy you'd have to put into an object to get it through the atmosphere and up to the L1 point. Huge.
    • Also calculate how hot the object would get from the friction. Very close to the amount of heat a satellite gets on re-entry. Hot enough to melt platinum I suspect.
    • When the objects gets launch
    • Electromagnetic launchers have to accelerate the sails to escape velocity, nearly 25,000 MPH. The drag on an object goes up as the square of the velocity. Try calculating how much energy you'd have to put into an object to get it through the atmosphere and up to the L1 point. Huge.

      Because, of course, we could not fold the objects into something smaller and have the sucker unfold in outer space...
  • I don't want to be a pessimist, but I hope they also plan for a way to bring it back down in a hurry if it has some unpredictable side-effect. Like some kind of auto-destruct mechanism or something.
  • ...man has yearned to destroy the sun. I will do the next best thing...block it out!"
  • once in place, I'm assuming this thing would be capable of generating quite a bit of solar energy beyond what it needed for any corrective propulsion... would it be enough to be worth trying to send somewhere else?
  • Electromagnets surprisingly enough require.... Electricity.

    Despite good intentions most electricity production still kicks out a load of CO2 and other gasses. I would imagine the energy demands on the magnets to launch the payloads over 10 years would consume a fair bit of electricity consumption so increasing the problem the shield is trying to solve in the fist place.
  • and let a smile be our umbrella.
  • Too late... Simpsons already did it. [wikipedia.org]
  • ... could they please try it out on a planet less valuable to us ? Venus, maybe ?
  • by SengirV (203400) on Monday November 06, 2006 @07:53AM (#16733863)
    ... of global warming. You know, the sun actually putting out more energy in the last 30-40 years - http://www.space.com/scienceastronomy/sun_output_0 30320.html [space.com]

    Why look for a scientific explanation when you can make it a political issue?
  • That's a really wacky solution you know. Why a giant shade? Who comes up with those exotic solutions? And why not a giant fridge with a giant ice tea in it. This would at least be stylish, you know!
  • It doesn't make sense to simply shade the earth. If you're going to the trouble of sending stuff into space you might as well set up a huge solar array [firstscience.com] that generates electricity and beams it down to the earth.
  • The National Academy of Sciences looked at a ton of geoengineering ideas several years back, and ultimately decided the solar shade method is NOT cost-effective at all. Instead, shooting inert particulate dust up into the stratosphere with big naval guns will reduce the amount sunlight getting to Earth for a lot fewer 0 figures on the price tag. (There's precedent, too - from naturally-occurring volcanoes and the like.)
  • If the plan is to launch these things using electromagnetic launchers, then I guess you'll need a shitload of electricity to do this... How is this energy going to be produced in a way that doesn't increase global warming substantially anyway? If the answer is a whole bunch of nuke plants, wouldn't opening said plants allow global warming to be reduced dramatically by closing fossil plants, making electric cars more economical, etc.?

Memory fault -- brain fried

Working...