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Earth Science

Solar Geoengineering 'Only Option' To Cool Planet Within Years, UN Says 138

Posted by BeauHD from the proceed-with-caution dept.
The United Nations Environment Program (UNEP) is investigating the potentials and dangers of solar geoengineering technologies, stating that these controversial interventions are humanity's "only option" to quickly cool the planet within years. An anonymous shares an excerpt from a Motherboard article: In a report published by UNEP in February, an independent panel describes what's currently known about so-called solar radiation modification, also called solar geoengineering, and concludes that, despite its great potential, it's not viable or even safe right now. Nonetheless, amid growing calls from governments to find an emergency brake for climate change -- and ongoing, independent efforts to develop solar geoengineering technology -- the UNEP is calling for a full-scale global review of the tech and eventual multinational framework for how it should be governed. The recommendations have some opponents fearing that this amounts to endorsement of adopting the technology -- a move that could create an even worse environmental crisis by messing with intertwined natural climate systems or pulling the focus away from mitigation measures, as well as further widening the inequalities that already exist as a result of climate change.

Solar radiation modification describes a range of technologies that aim to cool our overheated planet by reflecting incoming sunlight back out into space, or making it easier for heat coming off the earth to escape. Blocking out just two percent of sunlight could, according to some estimates, totally offset the warming that comes from doubling the amount of CO2 in the atmosphere from pre-industrial levels. It's a tantalizing prospect, but comes with a raft of issues. For one, as the report notes, the best large-scale evidence we have that it could even work is from volcanic eruptions, where the smog cooled the globe for a couple of years afterwards. Most of the actual research has involved climate modeling, theoretical analyses or cost estimates. Some groups have conducted small-scale indoor experiments of how the tech might work. No one's taken the trials outdoors yet.

Even if we knew more, it's not a be-all-end-all climate solution, said UNEP's chief scientist, Andrea Hinwood. "SRM technologies, should they be considered at some point in the future, do not solve the climate crisis because they do not reduce greenhouse gas emissions nor reverse the impacts of climate change. The world must be crystal clear on this point," she said in a UN media release. What solar geoengineering might do though, is buy the planet some time. The UNEP report highlights that even if we fully halted CO2 emissions right now, it could take at least until the end of the century to see a drop in temperature. "Make no mistake: there are no quick fixes to the climate crisis," wrote UNEP executive director Inger Andersen in the report. "Increased and urgent action to slash greenhouse gas emissions and invest in adapting to the impacts of climate change is immutable. Yet current efforts remain insufficient." Despite firm opposition from some, the message from the UNEP report seems to be to proceed with caution. "While UNEP is concerned, it is naive to think research will cease and the issues will disappear. We cannot afford to bury our heads in the sand," said chief scientist Hinwood.
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Solar Geoengineering 'Only Option' To Cool Planet Within Years, UN Says More

Solar Geoengineering 'Only Option' To Cool Planet Within Years, UN Says

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  • Law of unintended consequences (Score:5, Insightful)

    by sinij ( 911942 ) on Saturday March 04, 2023 @09:17AM (#63341683)
    Climate is extremely complex system full of feedback loops. Assuming that we sufficiently understand it to know that geoengineering is both necessary and beneficial is hubris and not based on any established climate science.

    • Re:Law of unintended consequences (Score:5, Interesting)

      by Joce640k ( 829181 ) on Saturday March 04, 2023 @10:37AM (#63341835) Homepage

      Weird but true:

      The exact same people who are currently being told their climate models are wrong will be the the ones the deniers call on to perform this complex and dangerous geoengineering for them.

      • So which of these statements is true:

        A. Climate is understood well enough that we can tell that human activity is leading to catastrophic changes.
        or
        B. Climate is not understood well enough to allow humans to come up with safe and effective methods of controlling it.

        Or if both are true, please clarify.

        • Re: (Score:3, Insightful)

          by sonlas ( 10282912 )

          So which of these statements is true:

          A. Climate is understood well enough that we can tell that human activity is leading to catastrophic changes.
          or
          B. Climate is not understood well enough to allow humans to come up with safe and effective methods of controlling it.

          Or if both are true, please clarify.

          Both are true.

          Nuclear fusion has been well understood since a long time. And we know enough about it, such as: I can tell that if you expose yourself to a nuclear core, that will lead to some catastrophic changes to your body (i.e.: death, although we could argue if it would really fall in the definition of "catastrophic").

          Yet, we are still decades away of coming up with safe and effective methods of controlling it to the extent of generating power from nuclear fusion.

          Now, about climate and geoengineering:

          • So which of these statements is true:
            A. Climate is understood well enough that we can tell that human activity is leading to catastrophic changes. or
            B. Climate is not understood well enough to allow humans to come up with safe and effective methods of controlling it.

            Both are true.

            Correct, both.

            After half a century of detailed study and modeling by literally thousands of scientists, accompanied by an intensive campaign of global measurements totaling tens of petabytes of data gathered every year (!), we have a pretty good understanding of the global climate under current conditions, allowing us to do good modeling response to one variable, carbon dioxide, such that we can state with confidence that human activity is responsible for observed warming; and we can even make predictions

        • Climate is complex enough that we can't possibly make the claim to be able to understand it well enough to model it.

          Note that this is not a justification to not be cautious about the environment. On the contrary, when in doubt, the principle of precaution applies.

        • Re: (Score:3)

          by tragedy ( 27079 )

          So which of these statements is true:

          A. Climate is understood well enough that we can tell that human activity is leading to catastrophic changes.
          or
          B. Climate is not understood well enough to allow humans to come up with safe and effective methods of controlling it.

          Or if both are true, please clarify.

          False dichotomy. Climate is clearly better understood by some than others. For example, anyone proposing "geoengineering" approaches that basically amount to massively polluting the atmosphere in order to dim the planet very clearly don't understand that the problem is retention of heat from sunlight, not there being too much sunlight. We actually need that sunlight to do things like survive, so blocking it is insanely foolish. The only "geoengineering" that would make any sense would be steps to prevent th

        • A. Climate is understood well enough that we can tell that human activity is leading to catastrophic changes.
          or
          B. Climate is not understood well enough to allow humans to come up with safe and effective methods of controlling it.

          Or if both are true, please clarify.

          C. Greenhouse warming, like every other environmental problem we have faced over the years, is a problem for which various engineering solutions have been suggested. But it is ideologically necessary to prevent any of these approaches from even being tried by making vague assertions that the problem and any fixes for it are equally apocalyptic.

          • Re: (Score:2)

            by q_e_t ( 5104099 )

            But it is ideologically necessary to prevent any of these approaches from even being tried

            Whose ideology? You seem to be assuming there is some sort of global ideological conspiracy of governments left, right, centre, and scientists and companies of every ilk. It's not very likely, is it?

    • Fight human-made climate change with another human-made climate change. What could go wrong?

    • Re: (Score:2)

      by ceoyoyo ( 59147 )

      Do you think maybe that's why the UN is suggesting to consider studying it, just in case we need it in a hurry?

    • Re: (Score:2)

      by Reziac ( 43301 ) *

      Also, if they fuck up (which is probably a given), they may well kill all life on Earth.

      Most of the world can adapt to more warmth (if it were warming, which the longterm historical record says it is not), but bring on another ice age and we may be lucky to grow any crops at all, and avoid a snowball Earth.

      Oh, wait, killing all of humanity isn't a bug, it's a feature.

      • Re: (Score:2)

        by suutar ( 1860506 )

        If only we were talking about a timescale where long term historical records mattered. The whole issue is that it's happening faster than things (particularly but not exclusively us) can adapt to.

        • Re: (Score:2)

          by Reziac ( 43301 ) *

          I guess no one and nothing adapts to seasonal changes, then...

          I have personally experienced -72F to +122F, and LIVED!

  • If you could put something big enough at L1 to block some of the sunlight reaching the planet, maybe that would be reasonable. GLWT. But putting stuff into the atmosphere is a terrible idea.

    • Yeah, because we need to breathe that stuff constantly everyday

    • Roughly speaking to block 2% of incoming light would require parking something with the combined area of Alaska and Texas at L1. That is a daunting prospect.

      • I'm getting slightly bigger than Texas, or only half as big as Alaska.

      • This is not the international standard of using the size of Belgium for such things.

      • It's a lot, but it doesn't have to be one thing.

      • Where do you get 2% from? The energy imbalance [wikipedia.org] is only about 0.3% of incident radiation. Given the Earth's albedo of 0.30, a shade of ~0.5% would be about right. Still a daunting prospect though...
    • "something big enough" is the key. A guy on youtube did the calculations of what it would take to create such a space shade and it's pretty eye-opening. We're talking about hundreds of starship launches. L1 also isn't some permanent parking spot, you'd still need to employ thrusters to keep the shade in place. At that size the shade is like a giant solar sail which will keep getting pushed. https://www.youtube.com/watch?... [youtube.com]

    • Since you have quoted him in your sig, I suggest reading Neal Stephenson's recent work, Termination Shock [nealstephenson.com]

      At 450 pages it is pretty slim for a Stephenson tome, and he includes a bibliography.

      I found it to be an enjoyable read

  • So we are fucked then? (Score:4, Informative)

    by gweihir ( 88907 ) on Saturday March 04, 2023 @09:27AM (#63341715)

    Because _that_ is wayyy out of what the human race can actually accomplish. Carbon-capture where it is produced (power generation) and producing energy carbon-neutrally is _easy_ in comparison and we are not even managing that.

    Also, unintended consequences much? For example, any rapid temperature change will completely screw up farming, rain patterns, etc. To be fair, that could give is the rapid population decrease down to 500M or so that is direly needed. On the minus side we will not have a high-tech civilization left after that.

    • Re: (Score:2)

      by Eloking ( 877834 )

      Are we fucked?

      Well, it depends what 'we' means.

      If you mean yourself, it depends where you live.

      If you mean all living things on Earth, then yeah. We're heading to a 3.0C (2.5C with a bit of luck) increase so we can expect a pretty decent mass extinction.

      If you mean humanity, not so much. There's nothing foreseeable that humanity cannot overcome. Bees extinction? Nope. Increase in hurricane? Not even close. Sea rise? Won't happen.

      Humanity (in developed countries) is no longer dependent of nature. That massiv

      • Re: (Score:2)

        by gweihir ( 88907 )

        If you mean all living things on Earth, then yeah. We're heading to a 3.0C (2.5C with a bit of luck) increase so we can expect a pretty decent mass extinction.

        I agree to that. May still get to 4C or more, given how many people fight tooth and nail to be able to continue making it worse.

        I do not share your optimism about the human race though, humans are pretty fragile and more so today.

      • There's nothing foreseeable that humanity cannot overcome. Bees extinction? Nope. Increase in hurricane? Not even close. Sea rise? Won't happen.

        If we're were on Reddit I'd get that !Remindme bot to save this for 2038.

      • Is there a difference between going extinct and being reduced to small bands of people struggling to survive? High tech will never come around again as we've already stripped the surface of easily accessible metals, fuels, etc. The biosphere which we used to plunder will be reduced down to nothing.
      • Last I heard, humans were living things.

      • Re: (Score:2)

        by ceoyoyo ( 59147 )

        Unless we decide to go crazy and launch all the Nukes, Humanity is not going anywhere.

        A couple good global crop failures and the nukes would get launched. It still wouldn't kill everybody, but either the crop failures or the nukes would do a number on civilization.

      • Re: (Score:3)

        by suutar ( 1860506 )

        Humanity won't go extinct. Modern civilization could however go poof.

    • Because _that_ is wayyy out of what the human race can actually accomplish. Carbon-capture where it is produced (power generation) and producing energy carbon-neutrally is _easy_ in comparison and we are not even managing that.

      Yep. But it's easy in the minds if the deniers - just fly up there and dump some stuff in the air.

      • Re: (Score:2)

        by gweihir ( 88907 )

        Because _that_ is wayyy out of what the human race can actually accomplish. Carbon-capture where it is produced (power generation) and producing energy carbon-neutrally is _easy_ in comparison and we are not even managing that.

        Yep. But it's easy in the minds if the deniers - just fly up there and dump some stuff in the air.

        Yes, that seems to be the mind-set. Pretty what actual engineers get beaten out of them in their education. Simplistic things never work or come with huge problems.

    • Because _that_ is wayyy out of what the human race can actually accomplish.

      It's really not. You should look at some of the geoengineering proposals. Many of them are not only within the capabilities of any major nation state, but even within the capabilities of superwealthy individuals . For one (quite entertaining) example, read Neal Stephenson's "Termination Shock", which is about exactly this topic: The nations of the world have not taken action to directly cool the planet, so a private consortium does -- and without much coordination or planning, creating international crises

  • If climate change is as they say then all countries should be putting aside all other concepts, shutdown all non-critical co2 producing activity and save the world.

    If not as they say then even considering fucking in unknown ways with the entire planet is suicidal global folly.

    The route we have chosen is to instead politicize what should be a pure science question well past the point where it is possible to know what's really going on. Everything is agenda driven. And no, there is not a good guy and a bad

    • Science can only tell you what things are and suggest what they might become, but it doesn't direct funding towards engineering projects of this nature - that's the job of governments (because you need to coordinate and agree as it's a shared planet) and thus it is the realm of politics, international politics, even. So I really don't understand what you expect scientists to do in terms of implementing a global effort such as solar engineering.

      • The scientists are employed by the politicians and others with an agenda. No particular agenda for all scientists but always an agenda. The entire field of climatology has been politicized and it hasn't been possible for decades to truly know wtf is really going on, even assuming that's truly possible with the knowledge we currently have.

  • This is serious. So you need to decide if you are more scared of nuclear power or climate engineering.

  • but it's neither desirable or pretty, nor suitable to discuss in any social setting: it's called mass sterilization [wikipedia.org].

    Like it or not, humanity has long passed the threshold of sustainability. It's just that most people in rich countries don't think about it every day because a vast majority of the poor are so poor that they can stay rich, well fed and ignore the issue. But one day everybody will be reminded every day in very concrete ways that there are way to many humans on this planet.

    • More realistic solution, hint: an US citizen emits like 8x more co2 than an indian citizen. Birth control should have been applied way earlier, plus you have to make it fair implying equal living standard for everyone thus impossible.

      • Nature doesn't care about anybody's notion of realism. Either humanity curbs its own number voluntarily - be it Indian, Chinese, French or Americans - or it will. By the looks of it, nature will act first.

        • USA reducing their emission(and thus consumption) by 8 is like reducing world population by 2 billion, it was the hint. Overconsumption is a problem in all rich countries by the way, USA has just the worst number.

      • More realistic solution, hint: an US citizen emits like 8x more co2 than an indian citizen. Birth control should have been applied way earlier, plus you have to make it fair implying equal living standard for everyone thus impossible.

        India: 1,408,000,000/1,240,000 sq mi = 1,135.5
        USA: 331,900,000/3,797,000 sq mi = 87.4
        = 12.99x people per square mile.

        I think we can afford 8x more wastefulness when we have 13x the space to live sustainably. The US is one of the least dense industrial nations in the world, the rest of the world is going to have resource problems long before we do, india especially with their disappearing glacial water situation.

        • Population density has nothing to do with co2 emission. And there is nothing stopping natural resources exhaustion even in a big closed country.

    • If you reduced the population enough to solve the problem without making other fundamental changes, you couldn't sustain your high-tech society, because whoever's left will still want to live a rich lifestyle.

    • Like it or not, humanity has long passed the threshold of sustainability.

      Malthus, you at it again?

  • That which can be used to heal can also be used to destroy. Even it it was technically feasible, who would control the "squelch knob" for such a system? As you monkey around with global climate, there will be winners and losers. Who decides that it is better to have a moderate climate in one place at the expense of converting another to a desert?

  • It's time to force all of those UN agencies and Councils and whatever off to their own island in the ocean.

    That way they can gain firsthand experience with rising ocean levels.

    Perhaps then they will stop yapping about "warm this" and "climate that", and actually find the "intestinal fortitude" to actually do something about it.

    • Except for the small detail that those small islands do not actually seem to be disappearing at all, and life there is good. But, I say, do send them there, just make sure they don't have telecom service to keep bothering the rest of us.

      • except they are disappearing, just listen to the people living on islands loosing land.
        It's f.cking real, open your eyes don't just listen to morons on social media.

  • Natural grasslands and forests that have been turned into deserts through poor farming, ranching, land and water management.

    The solution is returning native species to these areas. Both plant and animal.

    The facts are out there. The research has been done. Land has been restored. No politics needed.

  • How many instant-on appliances are plugged in right now? Why do we need a 4,500 car to get a gallon of milk. Part of the problem is: if you are rich, the energy cost is meaningless.

  • If we don't wipe ourselves out in the next few hundred our thousand years, we (or our intelligent successors) can and should seriously consider geoengineering.

    I think we'll (or our intelligent successors) want to prevent, or moderate, the next ice age, which will naturally come due to orbital and procession cycles. Even if we (or our intelligent successors) are beyond needing to grow food, we (or...) should become good stewards of the planet and maintain a good, productive ecology.

  • Just plant f.cking trees
    it's f.cking simple
    it's f.cking natural
    the technology is available now

  • Geoengineering tech is likely to be expensive to implement at scale, but there are projects that are not difficult to demonstrate experimentally as having a minimum measurable effect. Any technology that can't run away should be tested in this way, whether it's scattering some sulfur in the upper atmosphere or motoring some inflatable bubble material out to the L1 Lagrange point. If it doesn't work, just stop doing it. The sulfur will drift back down and anything at L1 will gradually float away in the absen

  • ... now only remains to see who will profit as it certainly won't be humanity.

    Government money is the prize, scientific belief that 'we know everything we need to know', and the average person's desire 'I want it now!'.

    Human avarice, arrogance, and impatience writ large.

    "Hell yeah we can fix the planet! A little money and our experts will sort it out now!"

  • I read the report unfortunately _after_ I posted ("And voila, ...") The report finds SRM is not yet ready, engender unknown risks, etc. In fact, this has to be a test of how slashdot people react because beneath the title in the summary is a direct contradiction to the title:

    "Even if we knew more, it's not a be-all-end-all climate solution, said UNEP's chief scientist, Andrea Hinwood"

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