The likelihood of unilateral solar geoengineering

&quot;We don&#x27;t know who struck first, us or them. But we know that it was us that scorched the sky. At the time, they were dependent on solar power and it was believed that they would be unable to survive without an energy source as abundant as the sun.&quot;<p>- Morpheus, The Matrix

I&#x27;m continually surprised that this idea gets so much traction. While possible to build, it&#x27;s also strictly Temporary and just leaves us with a worse problem later on. We&#x27;ll just need a bigger one, 20 years down the line, when CO2 levels keep going up! At some point, it&#x27;s pretty obviously a non-solution.<p>Let&#x27;s put this energy into Nuclear Power and CO2 recapture; and actually fix things.

&quot;If your solution closely follows the story line of the Simpsons, perhaps reconsider&quot; – The Simpson Solution Axiom

This story about urban albedo interested me earlier [0].<p>Painting roofs and roads white, and simply having more green parks instead of paved areas would actually make a difference.<p>[0] <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;context?id=39356361">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;context?id=39356361</a>

This title is breaking HN&#x27;s guidelines by being linkbait. (&quot;<i>Please use the original title, unless it is misleading or linkbait</i>&quot; - <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;newsguidelines.html">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;newsguidelines.html</a>)<p>Can anyone suggest a less baity title? I looked through the text trying to find an accurate, neutral, representative phrase and couldn&#x27;t find one. That&#x27;s unusual and probably a bad sign.

Various small organisations are already doing a number of geoengineering projects on the ocean and various other biomes&#x2F;habitats. Its simply a matter of time and there is currently no framework to stop it happening, anyone with the funding can just do this and break no laws. If it all goes wrong due to unforeseen consequences we all suffer. Just like climate change really, people on the other side of the planet are causing harm to everyone and refuse to stop.

This was the plot of Termination Shock by Neal Stephenson

I wonder if simply tainting the fuel of airliners with sulfur would be good enough for a meaningful effect.<p>A half a percent in the global jet fuel supply would put that order of sulfur into the atmosphere, a bit lower than what I think is being proposed here. But adulterating the fuel supply would be affordable and equivalent to a smallish tax on flight.

&gt; and (more practically) high-altitude balloons filled with sulfur and hydrogen&#x2F;helium.<p>Helium&#x27;s a bad thing to fill with because it&#x27;s a limited resource. Hydrogen is bad because it&#x27;s a sink for greenhouse gas eliminating hydroxyl. <a href="https:&#x2F;&#x2F;e360.yale.edu&#x2F;features&#x2F;natural-geologic-hydrogen-climate-change" rel="nofollow">https:&#x2F;&#x2F;e360.yale.edu&#x2F;features&#x2F;natural-geologic-hydrogen-cli...</a><p>: For instance, some of the hydrogen released will react with the atmospheric compound hydroxyl, creating ozone, which in the lower atmosphere is a greenhouse gas. And by using up hydroxyl, which is the atmosphere’s main cleansing agent, hydrogen will leave less of the organic compound available to break down methane and other greenhouse gases, resulting in those gases lasting longer in the atmosphere and causing additional warming.

The idea that a billionaire is just going to yeet a program together is pretty far fetched. Even at &quot;only&quot; $20 billion dollars a year, there are less than a dozen billionaires in the world with that kind of free capital. And none of them could sustain that kind of spend for more than 1-2 years.<p>The &quot;country of no choice&quot; similarly applies to only a small handful of countries that have no decent way of mitigating climate change but also have the funds and resources to do SRM. So really, just China (which has already shown enthusiasm towards geoengineering) or India.<p>The primary human response is still going to be crop adaptation and mass economic migration. I think we are going to have to see a lot more of this before we see someone dim the sun.

Are there ways this could be done with rapidly biodegradable materials, such that e.g. it would need to be continually done year after year or else the sky would return to the exact same state it was in before? Also, living in Arizona with 120F&#x2F;49C summers, I sure wish someone could come up with some geography-wide sunshade!<p>I guess that will need to be after they stop growing the city forever, and stop paving the earth of my state with black asphalt and concrete, and stop giving all our groundwater to lettuce and alfalfa farming to be sent out of the state or country entirely.

What wavelengths of light would be reflected?<p>My understanding is that the way greenhouse gas induced warming works is that we have incoming solar radiation over a broad range of wavelengths.<p>Some of that ends up being absorbed by various things on the surface which heats them which causes them reradiate some of that absorbed energy as infrared.<p>Greenhouse gases absorb infrared, and so some of that reradiated energy that would have been radiated back into space gets trapped by those gases.<p>From a purely reducing warming perspective then it probably wouldn&#x27;t matter much what wavelengths you are reflecting. Any light you stop from getting absorbed and turned into heat below would help.<p>But incoming radiation often does useful things before or instead of getting turned into reradiated infrared. For example it may be used by plants for photosynthesis.<p>It would seem then that if reflecting light in the stratosphere to reduce warming you&#x27;d want to try to avoid deflecting wavelengths that are important for photosynthesis or other useful things.<p>You&#x27;d want to pick wavelengths that don&#x27;t do much other than just end up getting absorbed at the surface. Does sulphur do this?

I&#x27;ve been fascinated by marine cloud brightening, a related technology. I&#x27;d love to see that explored first, as it seems cheaper and lower impact. Still, if it was a choice between pretending that we&#x27;re going to effectively mitigate climate change at this point without geoengineering, and darkening the sun, I&#x27;d say darken the sun.

I think I read somewhere the CO2 absorbed by ocean causes acidification which the ecosystem needs a bit of adjustment to live with.<p>I don&#x27;t think the a sun shade would do anything for that.<p>That said the Simpson&#x27;s quotes in this thread are making laugh enough that I&#x27;m starting to get onboard with this plan whatever my initial doubts.

Did some people start reading Neil&#x27;s book, Termination Shock?

Probably too late with this comment, but from today&#x27;s WSJ: &quot;Scientists Resort to Once-Unthinkable Solutions to Cool the Planet&quot;<p>Lends some support to the author&#x27;s thesis. A little unsettling that the reflective SRM material in the WSJ article isn&#x27;t sulfur (apparently) but something proprietary of undisclosed composition.<p><a href="https:&#x2F;&#x2F;www.wsj.com&#x2F;science&#x2F;environment&#x2F;geoengineering-projects-cool-planet-weather-f0619bf7" rel="nofollow">https:&#x2F;&#x2F;www.wsj.com&#x2F;science&#x2F;environment&#x2F;geoengineering-proje...</a>

well written. terrifying but practical.<p>hopefully calcium carbonate experimentation gets underway so we can learn about its effects.

Would this process work the same way climate change is warming? Because climate change, while on average increasing the global temperature by 1.5C, has pretty big variations in actual temperature decrease by region. It&#x27;s important if you use sulfur to decrease the temperature that this decrease counteracts regional temperature increases and not just average global temperature.

And somehow, in the US at least, we don&#x27;t even have broad agreement that climate change is real, happening, and will dramatically adversely affect humans for centuries to come.<p>Anyone have any good resources or techniques for having honest discussions with friends and family that simply refuse to believe a problem even exists? Real solutions will only come once we admit there&#x27;s a problem.

Sulfur is probably not the best agent to do it, but we know that it works from the unintentional ship fuel experiment.<p>In any case, if 2023 wasn&#x27;t an exception, I&#x27;d rather have someone start a program this year. It can always be stopped or scaled down. And I am confident that renewable energy, electrification, and battery deployment will continue unabated anyways.

In terms of Murphy: &quot;If there is a wrong way to do something, then someone will do it.&quot;

The simpler solution is build a damn lot of solar on Earth and use the energy to suck CO2 out of atmosphere. I did the calculations, it was something like the area of UAE equivalent solar to have enough energy to suck ALL CO2 from the atmosphere.

Have we thought about impact on plant life? Like wheat? Seems like a bit of a problem for a solution like this. One might say that plant life literally evolved for the solar conditions we currently have.

The long term fixes for excess atmospheric CO2 are (IMO):<p>- Using energy more efficiently (e.g. insulating homes better instead of burning more fuel in the winter)<p>- Electrifying as many energy demands as possible (heating, ground transportation, materials production, chemical synthesis)<p>- Replacing fossil-powered electricity generation with low emissions sources: solar, nuclear, wind, hydroelectric, geothermal, tidal<p>- Accelerated silicate weathering for carbon dioxide removal (basically, crushing a lot of alkaline mafic rocks so they react faster to neutralize CO2 that&#x27;s already in the atmosphere and the oceans)<p>The IPCC proposes carbon dioxide removal too, calling for &quot;net negative emissions&quot; to neutralize CO2 that has already been emitted [1], except they give examples of afforestation, reforestation, and bioenergy with carbon capture and storage as removal techniques. (I personally think that those are poorly scalable and will not make much headway compared to silicate weathering, but I&#x27;d be happy to be wrong.)<p>What about the transitional time before we get to &quot;the long term?&quot; The majority of global electricity still comes from fossil fuels. Most road vehicles sold today burn fossil fuels. Even after we reach the tipping point where most vehicles are electric, the old ones may continue to operate for decades.<p>In the meantime, CO2 that has already been emitted is trapping more energy from sunlight and raising temperatures. Once temperatures go up enough, there are bad feedback loops where e.g. tundra thaws, microorganisms start releasing the previously frozen carbon compounds, and we get vast new emissions from thawing regions <i>even as</i> direct human emissions fall. In other regions, temperate forests may dry out, burn, and transition to different biomes with lower carbon sequestration capacity.<p>That&#x27;s why I think that solar radiation management will be needed. It can break the feedback loops where higher temperatures denude forests and release vast quantities of soil carbon. It doesn&#x27;t directly reduce emissions or draw down atmospheric CO2, but it keeps temperatures down so there&#x27;s time for the energy transition and CDR techniques to stabilize and reverse the atmospheric CO2 excess. A world with 550 PPM of atmospheric CO2 is bad, but a colder world with 550 PPM can be stabilized while a warmer world at 550 is going to keep going up even if anthropogenic emissions are slashed.<p>[1] &quot;What are Carbon Dioxide Removal and Negative Emissions?&quot; <a href="https:&#x2F;&#x2F;www.ipcc.ch&#x2F;sr15&#x2F;faq&#x2F;faq-chapter-4&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.ipcc.ch&#x2F;sr15&#x2F;faq&#x2F;faq-chapter-4&#x2F;</a>

Its not fair that you guys keep changing the funny titles after i come up with a zinger for them.atleast give me a day or two to make my dimsum jokes before you make it serious again,....

Good. I mean, not <i>good</i> good. But better than the alternative.

What a horrible idea. Equivalent of kicking out your ill child with a fever into the frosty night to &quot;cool down&quot; or ordering a diet coke to fast food meal.

I feel this article was basically daring Elon to do it.

Dimming the sun is like the alcoholic proudly proclaiming they&#x27;ll be eating salads for lunch. It ain&#x27;t solving the actual problem.

We are already messing around Mother Nature with all the fuel burning and now you are double shafting it, what could go wrong?

Termination Shock by Neal Stephenson

Thus solving the problem once and for all!

We would rather block the sun than reduce the military industrial complex by 10%, the world&#x27;s largest polluter.

What could possibli go wrong?

&gt; #2 - Billionaires are getting interested<p>Yeah! So that they can keep on destroying the planet for profit.

Doesn’t Elon Musk have the means and the cult like following to do this unimpeded?

Behold, the great filter

Let&#x27;s hope these technocrat degenerates never come to that.

You&#x27;ll get in trouble with Big Solar for disrupting their production!

Whether or not you believe in climate-change, the interesting discussion to me is that climate change is a convenient justification for power-grabs by wannabe dictators. I&#x27;m not so sure that the elite will be so ready to give up that lever of control by simply tinting the sky. We&#x27;ll see, I guess.

It&#x27;s amazing that this solution has not been considered more openly and widely until now. It&#x27;s cheaper, more effective, and doesn&#x27;t require draconian regulations or near-impossible expectations on human behavior.<p>It&#x27;s also something that could be tested for a year. It&#x27;s not irreversible. It would allow the undeveloped world a chance to achieve a piece of the global wealth pie.<p>Why are so many people (especially environmentalists and climate scientists) so opposed to this solution?