Dimming the Sun to Cool the Planet | Hacker News Reader

Dimming the Sun to Cool the Planet

newyorker.com

22 pointssamizdis85 comments

"We don't know who struck first, us or them. But we do know it was us that scorched the sky".

For real. Sounds like a good way to accidentally kill ourselves

By replicating what volcanoes have doing since ... the earth was formed?

Let's hope volcanoes (or a a supervolcano) don't accidentally add to the effect then.

The impact is relative short. So sure maybe we'd engineer 1.0 C and a volcano would add 1.0C. So glaciers would start growing instead of shrinking, rain patterns would return to norms from recent history. The south pole would stabilize, and the major ocean currents would get healthier. I wouldn't expect anything too major though.

Sure if it's bad enough we'd stop adding sulfer and wait for the temp increases to resume.

An increase in ice caps can increase the Earth’s albedo and start a runaway cooling effect. Mass glaciation is a very real possibility.

Most people don’t understand that we’re still in the Quaternary ice age. This is simply an interglacial period. Key geological requirements for mass glaciation continue to hold. The two big ones being the existence of a sufficiently large polar continent and multiple oceans, as opposed to a single large ocean such as during the Pangea period.

In this thread, nobody seems to understand the concept of "slightly".

There is a dimming effect every time there is a sufficiently large volcanic eruption. https://www.scientificamerican.com/article/sun-dimming-volca...

This effect is slight - not visibly apparent, you'd have to use instruments to detect it. That would also apply to solar panels. But this is the same effect as global warming in reverse.

If we have a top-of-atmosphere insolation of, say, 1300W/m2, and an emission of 1299W/m2 (not exact numbers), that will cause warming. If we add reflection, can we get those numbers to balance once more?

And note that this stuff will fall out of the atmosphere over a period of time. It would be an ongoing expense to do.

I don't see it likely to happen, on sheer cost grounds.

An alternative slightly more long-term plan would be a solar shade at a Lagrange point. Could even be used for space solar power, although at this point we're into deep science fiction. The Mars trilogy posited a solar Fresnel lens which would be used to warm Mars.

> not visibly apparent

In fact it was quite visible. I remember how odd the sun looked during that time.

> I don't see it likely to happen, on sheer cost grounds.

The cost appears to be one of the things in its favor.

Gaslighting unwelcome.

It would be disastrous if a program in any way like this went ahead, because it would be seen as a substitute for fixing the root problem, would steal funding from the latter, and would do nothing to stop the ocean acidification that threatens the roots of the global ocean ecosystem.

Precisely. It's like installing plumbing to divert a roof leak instead of fixing the leak. "But we would have extra water from the leak!".

Or like using a painkiller to cure the hangover....

If we dim the sun, the brakes are off for burning fossil fuels, especially as yields from solar will decrease.

Great news if you're in the fossil fuel business, bad news if the side effects of burning fossil fuels besides the carbon emissions bother you.

In particular, ecosystem/habitat destruction would only be amplified by the dimming.

Except, you know, for the change in distribution of temperature with latitude, and changes in precipitation patterns, and acidification of the ocean. And the aerosols will change the color of the sky. The sun will be surrounded by a bilious corona of scattered light. But all that is still better than unaddressed CO2 emission.

The decrease in solar yield will be quite modest.

Your argument is like "discovering imperfect treatments for lung cancer just encourages smoking."

> "discovering imperfect treatments for lung cancer just encourages smoking"

Well yes, it does? The better the treatment the less reason to avoid it.

The monstrous part is then saying we shouldn't look for lung cancer treatments.

Eh not necessarily. Not all lung cancers are caused by smoking, nor is it the only thing influencing the decision. I'd imagine the ever increasing prices of cigarettes and a ban from smoking in public places play a larger role in discouraging it.

I wonder if that could backfire if the reduced irradiation would reduce the plants' ability to remove carbon from the atmosphere.

Plants primarily photosynthesize visible light (400-700nm), wherein proposals to 'dim the sun' are speaking of infrared light.

Serious but potentially seriously stupid question: If clouds cool the earth, and we have a fresh water shortage, what if we boil the oceans?

Hear me out.

What if we had large floating barges of dark surfaces floating in hot areas. And what if we set it up so the dark surface was just an inch under water. Wouldn't this cause the sun to evaporate more water than it normally would, thereby increasing clouds in the sky, and potentially addressing two climate issues at once?

There's probably a million reasons why that's stupid, but I can't think of them at the moment. Seems like a simple solution to a complex problem.

Low-atmosphere cloud causes more warming than reflection. The positive feedback loop between increased surface temperature and increased evaporation is part of IPCC modelling; the term you want is "radiative forcing".

If you want a ground solution, there's surprising value in painting roofs white and selecting light colored road surfaces. I believe there's even a material which is calculated to radiate in the less-absorbed bands, so it can have a positive cooling effect.

Thanks for this response, by the way! I forgot to reply. This was really helpful.

From the article:

Andy Parker, British climate researcher:

Unless we find a way to remove carbon in quantities not imaginable presently, dimming would be the only way to stop or reverse rapidly rising temperature

Can’t find the sauce, but MIT published a concept study about putting giant Mylar balloons at the L1 LaGrange point to reflect solar radiation as an alternative to aerosols.

A slight tangent, but there was an interesting experiment by Russia in the 1990s that involved solar reflectors on satellites to shine more light on the Earth. See Znamya (satellite): https://en.wikipedia.org/wiki/Znamya_(satellite)

>>> Dimming the sun

What could possibly go wrong?

Why on earth would anyone think a cooler but darker Earth is less of a catastrophic ecosystem change?

This is so wrongheaded that I’m actually wondering if this story was pitched by some group that wants to smear geoengineering. I mean, geoengineering has a lot of ideas in it that are (while still out there) much less viscerally horrifying than blotting out the sun.

It would be a slightly darker earth. The net warming from CO2 addition is a few watts/m^2. Insolation is something shy of two orders of magnitude higher. Dimming sunlight by a few percent is not a large change.

I'm gonna wait until we're sure about the effect on every living organism on earth.

Because that same standard is being applied to CO2 emission, right?

What a double standard you have.

Why would you consider a few percent of sunlight change to be meaningless whereas a few degrees (a smaller percent, temp should be considered in Kelvin) is extremely meaningful?

Why should I not? I'm at a loss to understand why you think you're making a good argument there.

There are far larger changes in insolation over the day and over seasons. Life is obviously less sensitive to these flucuations, than life would be to changes in temperature.

Each argument is symmetrical! There are large fluctuations in temperature over space and time as well! Presuming that one matters and one doesn’t is making an assumption that needs to be proven at minimum, whereas the null hypothesis should be something like “it is not clear what changing the baseline temperature or light levels of an environment will do, but it’s probably bad for the ecosystem”.

The size of the fluctuation in insolation is very much larger than the change in temperature.

One goes from 1000 W/m^2 in noon sun to, what, milliwatts/m^2 from starlight? Many orders of magnitude. Temperature goes from maybe 250K to 320K over the year, maybe, a change of maybe 30%?

Not all sunlight is the same, and the majority of the heat comes from some of the lesser-utilized parts of that spectrum.

> Why on earth would anyone think a cooler but darker Earth is less of a catastrophic ecosystem change?

It seems possible to me, although definitely not certain.

The worst consequence would be less photosynthesis and less food, but we have surplus food production capacity on Earth. And maybe even that could be avoided if the blocking happens mostly in the infrared regime that causes most of the heating.

On our current path, we have areas of the Earth holding hundreds of millions of people which are projected to become too hot for human life for some of the year. Action that avoids that has something going for it, even if it also has downsides.

Wasn't it this kind of desperation that led to the apocalyptic conditions of "Snow Piercer" ?

This may come as surprise, but "the argument from science fiction" is not actually valid. For example, it's probably not realistic to have FTL spaceships.

Thinking aloud, I wonder how feasible a mechanical shield at the Sun/Earth L1 spot could be? Seems more adjustable and less risky than atmospheric manipulation.

Whatever we do to protect the Earth, can be turned against us to destroy it, too.

Before we develop the technology to do this earth-cooling properly, we need to establish the ethics to make sure it is done properly.

Too often we technologists invent something that changes the world for the better, only to have it weaponised to make the world worse.

I sure hope the space nerds are aware of this cold, hard fact.

I wish I could recall (or find) the precise quote, but I do believe it was Mark Twain that said something like, "we are destined to outsmart ourselves.". No doubt we are a clever and creative species willing to tackle the thorniest of challenges. Except when it comes to changing beliefs and behaviours. With so much of climate change mitigation, we appear unwilling to change values and expectations, beliefs and behaviours. To drop our feelings of deservedness (especially relative to comfort and convenience and consumption) and to let go of human exceptionalism. No amount of extraordinary engineering will do as much for humanity as developing a reverence for the natural world and all that is in it rather than continue to hold values based on extraction and exploitation. We have a history of bad choices when meddling with nature [1]. I suspect there have been some successes, too, but we largely remain ignorant, to a grand degree, of the interconnectedness and dynamics of most natural systems and ecosystems.

[1] https://www.theguardian.com/environment/2022/nov/22/what-hap...

The hubris in the climate change cult --because that is what it has become-- never ceases to both amaze and horrify me. Unbelievable.

I have said this here many times. If we continue to listen to these brainwashed cult members we are going to succeed at killing everything on this planet.

In a rational world, anyone proposing to control planetary-scale phenomena should be laughed off the stage. This cult has gained foothold in powerful political circles. This drives billions (hundreds of billions?) of dollars for research and general-purpose nonsense. The greedy among us (universities and private enterprise) jump on that bandwagon and promote the nonsense because it makes them millions of dollars.

It's a horrific positive feedback loop with potentially devastating consequences. The sad part is we are wasting time and obscene amounts of money that could be put to work on the reality of climate change, rather than the fantasies they continue to erect to keep the money machine going.

NOTE: In a rational world you should be able to get just as much funding from government to disprove or counter these hairbrained schemes. How much of that funding you think is available? Zero. Therefore, if you depend on research funding to make a living or a university depends on it to keep a department funded, guess what your conclusions are going to say, every, fucking, time?

Today, if you are a researcher or a business and dare go against what the cult has decreed to be "The One and Only Truth", your career is over and your business is going bankrupt. That should make everyone take pause. This is nothing less than Orwellian.

Brilliantly put.

It really bugs me that people don't realize research funding is only available if you say what they want you to say. That should be a red flag of massive proportions. Science isn't made this way. One could argue in science it is essential to fund and support every reasonable effort to discover holes in hypothesis. We don't do that, at all.

Good news is that it is very difficult to go-up against reality. Eventually physics wins, brutally so.

The closest I have seen to a refutation of climate change dogma is a private paper by Google Research dating back to 2014. That's right, we have understood some very important things about this issue since at least 2014...yet nobody talks about it and, much worse, none of this research is funded. They are looking for one, and only one, conclusion.

https://storage.googleapis.com/pub-tools-public-publication-...

There are other realities that, once again, are brutally hard to avoid. For example, if tomorrow all of the US and China were to evaporate from this planet atmospheric CO2 would continue to increase. No effort to control this can produce a rate of change higher than about 100 ppm in 50K to 100K years. That's not a guess. We have known this for decades. All you have to do is analyze atmospheric CO2 ice-core sample data going back 800K years to reach this very simple conclusion.

The oil industry spends vastly more burying and trying to refute climate science than is spent on legitimate reasearch. The "everything is fine, keep drilling" camp already has 4/5 politicians and about half of the total money and resources, they don't need any help.

Also what are you even trying to argue with that second bit?

> Also what are you even trying to argue with that second bit?

A number of things. Perhaps the most obvious of them being that any proposed magical solution has to be compared to common sense baselines. We never do that.

Eliminating ALL of the US and China (as in: They evaporate from this planet and cease to exist) can't fix the problem. At all.

Taking that as a simple factual baseline, I can't think of a single proposed so-called solution that even begins to compare to such an extreme, much less actually reduce atmospheric CO2 concentration.

The fact of the matter is it will take 50K to 100K years. We can kill ourselves in the process. We are not going to make it happen faster. We can't do that. We would have to violate the laws of physics. That tends to fall under the "impossible" category.

Stopping it from increasing is overwhelmingly simple. Just stop digging up carbon and stop releasing carbon tied up in ecosystems. The methods for getting energy without fossil fuels are accelerating at 20% or so per year, and last year displaced about 1-2% of carbon producing final energy. Luckily noone is proposing solving the problem by Thanos snapping a quarter of the population, so you don't have to worry about something as obviously idiotic as that not helping.

As to removing it, there are on the order of a billion with enough wealth to wield about 10kW without dropping their quality of life below the people they stole the natural resources from. This is enough energy for direct capture and sequestration of 10-20 tonnes of CO2 using industrial means per year using current technology. There are also many biological means that would have even greater impact just using a fraction of the land used for pasture.

There is no technical limitation to undoing the damage in a century or even a few decades, merely one of political will.

So I reiterate. What is your point of bringing this up? Why are you repeating this? What are you even trying to say?

> There is no technical limitation to undoing the damage in a century or even a few decades

That's where you are wrong. That's where all of these hand-wavy so-called solutions are wrong.

It is impossible to do this in a century.

It is impossible in anything even remotely close to a human time scale.

A 100 ppm reduction in atmospheric CO2 takes a minimum of 50,000 years and, more than likely, somewhere in the range of 100K.

So many things people ignore in these arguments. For example, world-wide population will nearly double by the end of the century. We are 8 billion today. Even if we take a low estimate of about 11 billion, that's adding the equivalent of TEN USA's, two India's or two China's.

Imagine that. Add two China's to the planet and actually claim that we can UNDO atmospheric CO2 concentration inside of a century.

C'mon! Give me a break! Get real!

Enhanced weathering experiments indicate that slreading basalt dust over agricultural land in quantities roughly equal to iron tailings (a large portion can be thise exact iron tailings as it is often basalt hosted) would sequester 1ppm per year whilst improving yields. It is not enough to offset current activity, but it is enough to bring levels down to something less bad in fairly short order.

This is just one of many possibilities.

The last resort one is iron seeding the lowest-life portions of the pacific. It is proven to work at many times higher scale for much lower cost, but the potential harms are not yet fully understood.

Noone on the left wants this. It's a solution invented and pushed by people who want to keep using more energy and drag their feet in eliminating fossil fuels. We should be putting every ounce of effort we can into eliminating waste, transitioning to clean sourcez and better distributing the energy budget we have now so the people who have too little can flourish. Not coming up with reasons that those in the global north can consume even more.

Ah yes, I too have seen The Matrix (1999)

And Who Shot Mr Burns

What's worrying is that these stupid suggestions keep popping up all over the place.

It's as if there's now a concerted effort to push geo-engineering on a wider level.

I wonder why? Could it be money, and the fossil fuel industry trying to muddy the issues?

Geoengineering is our plan B, or even plan C.

It’s a bad solution, but I guess it’s good to have it ready in a drawer if things start going really wrong.

I hear what you're saying. But it's more than just a bad solution, it's not a solution.

It doesn't fix the core issue, which is too many Co2e emissions. Unless and until we address that, we're going nowhere long term.

Won't we get less solar power as a result? Maybe it's what Nuclear needs...

It sounds like the kind of big-centrally-planned-risk-unknown project the Nuclear lobby likes...

Not mentioned in the article, but sulphur-based geoengineering was the focus of Neal Stephenson's latest novel, Termination Shock.

Reading elsewhere talks about using huge solar arrays to collect energy. Perhaps they would also block out some sun?

In addition to all the other popculture references in this thread, there is a book about a billionaire doing this, it came out last year:

https://en.wikipedia.org/wiki/Termination_Shock_(novel)

Written by Stephenson (Blue Origin, Cryptonomicon, …)

Looks like men would rather dim the sun first than invest in nuclear energy. Sounds great.

Geez, it would've been good if we cooled it on the burning of fossil fuels, 50 years ago.

Bit late now.

It should be brighten the inhabitants to cool the planet

Quote:

it would cost Elon Musk, currently the world’s richest man, far less to fund such a mission than it did to buy Twitter—and he’s already got the rockets

I find it really interesting that today there are individuals who are able to fund projects that previously took the resources of an entire country to fund. It's got to be the invention of the Internet that has made this individual wealth accumulation possible.

Also, I'd like to see a list of all the suggestions that people have made for a better use of Musk's money than to buy Twitter.

just in time for GPT4

Sorry, who has such an authority over the entire globe? Totally ridiculous if you ask me... Some people trying to play god or w/e but they're not alone in the room.

Wasn’t this a Simpsons episode? Montgomery Burns wanted to block out the sun to discourage solar power use.

Who Shot Mr. Burns?

https://en.wikipedia.org/wiki/Who_Shot_Mr._Burns%3F

I think its a good idea and we should do it. I regularly see areas which were snow covered and white now brown and much warmer. Unfortunately its also the plot of https://en.wikipedia.org/wiki/Snowpiercer where it overshoots.

Are you serious? you don't have any concerns about the impact on animal life? plants? human quality of life? It seems completely insane to think this is a good idea

How about the concerns if we don't do geo-engineering? Seems difficult to guess which concern should be higher.

It's not hard to guess at all, i feel like everyone responding to my comment must be trolling. DIMMING THE SUN will have so many second and third order effects you have no idea about! this is madness

I promise I’m not trolling.

>have so many second and third order effects you have no idea about

So has raising the Earth’s temperature, in addition to all the severe effects we know about.

I don’t know how to compare those risks.

The point is that the effects of CO2 are so dire that even a very problematic half measure could be worthwhile. OF COURSE CO2 emissions should also be addressed; these efforts are just to emphasize how serious the problem is, that one would rationally have to consider such steps.

It is possible to be concerned about the viability of the ecosystem and still want to do geoengineering, mainly by being convinced that current trends point essentially an unviable ecosystem on incredibly short time scales.

For example, the wet bulb thermometer temperature forecasted for large swathes of land near the equator essentially means it's uninhabitable for mammals several weeks of the year.

Its the perceived choice between 1) Do nothing and watch everything die or 2) try something risky and if it goes wrong, watch everything die.

Those aren't remotely the choices! If we do nothing _everything_ will die? that is so absurd i don't even know how to respond to that. It's hard to not suspect you're trolling I can't believe someone actually for real thinks like this

Everything dieing is pretty far out on the bell curve. 99% of humans? That's inside the range of reasonable considerations given how little slack we've left in the system.

Nonsense. 99% of humans will refuse to adjust or adapt and just die? how can you actually believe this?

It comes down to how fast things change. No amount of optimism over comes the fact that you need ~10 megajoules of food and ~3 liters of water on a daily basis. Producing those things for 8 gigapeople involves a lot of infrastructure that took a decent amount of time to build working correctly.

Farmland and logistics hubs in places that no longer get rain water and have run out of aquifers to tap need to be replaced somewhere more fertile. Desalination plants to replace dried up rivers need to be built. None of these can be operated on credit because giving someone a years supply of water after a year of drinking nothing just washes the corpse.

If the numbers shake out that there's a 10% shortfall, which 10% of population volunteers to starve their children? Or do fights break out? How does those fights stay constrained enough to not damage already strained infrastructure exacerbating the problem?

This is not a guaranteed outcome, but if you've seen how wide spread "just in time" logistics has gotten over the last 20 years and think it's impossible, I applaud your optimism.

And also don't want you anywhere near disaster planning.

We don't disagree that bad stuff can happen, but nothing you've responded with has convinced me 99% of everything dying isn't hysterical

It's totally doable in a limited way (low half-life blockers).

Even if it works perfectly, there at least one way it may backfire. Right now the increase in temperature is unprecedentedly fast, but many organisms can still adapt because the rise is spread over decades.

If at any time during the next couple of thousands of years our society is unable or unwilling to send the required payloads to cool earth, then the temperature will increase by several degrees in a few years, and fewer organisms will be able to adapt.

The thing about solar geoengineering is that, if you stop spraying, the particles settle in a matter of years and we're back to +1.5C again. I'm tempted to say that the possibility of an overshoot is nigh-impossible; but it's more the case that it's quickly reversed because we're still fighting uphill against all the heat we trapped under a blanket of carbon.

Not just back to +1.5C, but to where you would have been by that time.

Meanwhile, the whole ocean ecosystem has collapsed as acidification continued on up. The primary protein source of a billion+ people has vanished. They do not starve quietly.

Why is it always a plan straight out of sci-fi rather than "yeah we'll use a mix of renewable and nuclear energies, heavily reduce our dependence on fossil fuels, and create combustible fuels from renewable resources".

Obviously this plan is hard but is it harder than dimming the sun? the fucking SUN?

- is dimming the sun reliable?

- can the sun get too dim? What happens when a volcano erupts, dimming the sun's effect even more?

- Will we ever need to reduce the amount of sulfur in that atmosphere? how do we do that?

- How do we globally coordinate throwing sulfur into the atmosphere when we can't globally coordinate management of climate change?

- Does this help with air pollution in any way?

I want investment into the reasonable solutions to climate change that already exist. Telling the Koch family "Oh no, we can fill the atmosphere with sulfur and you can continue to dump garbage into the sky for 30 years" is laughable and it basically means that nothing but increased air pollution is going to happen for 30 years.

I'm not trying to be such a downer on this plan, and if it can safely and effectively help curb/reverse some of the effects of climate change that's incredible.

That said, we already have decades of research and billions of dollars invested into much more feasible methods to help curb climate change, and I can't really see why the top polluting countries of the world would start geoengineering when they haven't started implementing policies for the things that we know for sure work.

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