https://bigthink.com/surprising-science/harvard-scientists-controversial-plan-dim-sunlight?rebelltitem=6#rebelltitem6

 

https://youtu.be/N50tIzzPlg8

 

Would it not be better to send a rocket with nanoparticles and to dispers it between earth and sun?

 

I read in the book "Fully Automated Luxury Communism" if the average temperature of the earth rises above 6 °C all beeings with lungs die, because the methane brakes out.

Edited January 21, 20214 yr by Sandzak

Any reflectors in space will need to have station keeping capability, ie have the means to move around ie be little (or very big) spaceships. Because any inert material will be pushed out of position (presumably Lagrange zone between Sun and Earth) by sunlight and solar wind. I don't think we could build up low emissions space launch capability even if there were funds for it - and is this to be an alternative to cutting emissions? Dumping dust in the atmosphere is just a thought bubble, not any kind of real option. It offers no alternative to shifting away from fossil fuels to clean energy - an approach which is already gaining momentum.

Most leading climate research groups have doubling of CO2 making between 2 and 6C. The doubling depends on what we do, within discussion where action and inaction are inverted; we are acting to emit huge amounts of CO2, many times more than all other kinds of waste. I don't think we will die from methane - there isn't that much of it - but big releases would probably be a part of getting to 6C.

As for what happens with 6C of warming? That is a world I find hard to contemplate - I live somewhere where summers can already get unbearably hot and drought and catastrophic fires are showing signs of increased intensity already, at 1C. If economies and societies are so fragile that a transition to zero emissions is fiercely opposed then how much more fragile with the 6C that unconstrained fossil fuel burning will bring? Which over land here could be 8C rise in local air temperatures; I think heatwaves would kill crops and livestock and remnant ecosystems. How do you feel about refugees?

But the capacity humans have for making bad situations a lot, lot worse - good governance seems even more essential than ever. And if we cannot manage that now, how much harder in a world changed out of recognition.

 

Quote

How do you feel about refugees?

The people in need, have not the money to leave their country, just the rich.

 

Focus should be to help the people in need. More Refugees and the West elects neo-fascists like Trump

15 hours ago, Sandzak said:

https://bigthink.com/surprising-science/harvard-scientists-controversial-plan-dim-sunlight?rebelltitem=6#rebelltitem6

 

https://youtu.be/N50tIzzPlg8

 

Would it not be better to send a rocket with nanoparticles and to dispers it between earth and sun?

 

I read in the book "Fully Automated Luxury Communism" if the average temperature of the earth rises above 6 °C all beeings with lungs die, because the methane brakes out.

!

Moderator Note

Can you please summarize what you are linking to, as required by our rules?

 

The Swedish government approved a Harvard research group test about distributing reflecting aerosol in the atmosphere, to test the cooling effect of the concept.

Edited January 22, 20214 yr by Sandzak

This past week, an experiment in geoengineering.

https://www.scientificamerican.com/article/geoengineering-test-quietly-launches-salt-crystals-into-atmosphere/

 

Geoengineering Test Quietly Launches Salt Crystals into Atmosphere

A solar geoengineering experiment in San Francisco could lead to brighter clouds that reflect sunlight. The risks are numerous.

 

CLIMATEWIRE | The nation's first outdoor test to limit global warming by increasing cloud cover launched Tuesday from the deck of a decommissioned aircraft carrier in the San Francisco Bay.

The experiment, which organizers didn't widely announce to avoid public backlash, marks the acceleration of a contentious field of research known as solar radiation modification. The concept involves shooting substances such as aerosols into the sky to reflect sunlight away from the Earth.

The move led by researchers at the University of Washington has renewed questions about how to effectively and ethically study promising climate technologies that could also harm communities and ecosystems in unexpected ways. The experiment is spraying microscopic salt particles into the air, and the secrecy surrounding its timing caught even some experts off guard.

Hi All,

I am Joey and I am new here. My apologies for any mistakes.

Anyway, I came to this forum to discuss exactly this. Well kinda like this.

Ever since I was a kid (teen. Big kid), I have wondered why we not 'block' the sun. Sending up a couple of sunshades sounds like a plan on the surface, but the world economy would not be able to support the transportation cost of these shades into orbit.

Then some 20 years ago we got Graphene, and the same idea crossed my mind again. But this time I dismissed it simply because even if we can get shades in place, you won't be able to keep them in place.

But than, quite recently, I got the idea to dispense powder into space. My first questions; Is it technically and economically feasible. I think the answer to both questions is yes.

After I explored my idea, I noticed that GEO-Engineering is actually a 'thing' and that quite a few people are looking into that. Including using aerosols. I even saw a study on the use of diamond powder.

But, I was looking at carbon powder. It's absorption rate and its reflective properties. My motivation here is that Graphene, being only a single atom thick, still manages to stop 2.5% off the sunlight. And this is enough to reduce the global temperature to pre-industrial levels it appears. Now considering that Graphene is only an atom thick, covering 3,000km2 with this is quite incredible I figured. It appears that when this is in powder form it has slightly better reflective properties, so this would be a win. We can use dispensers in LEO who will be loaded and slowly disperse their load into LEO. By dispersion on different latitudes, you will likely even be able to use different cooling rates at different latitudes. Depending on the altitude, the carbon powder will slowly disappear, but it will likely take a few years to have reduce the amount of carbon by half.

As to cost? You need to install 75 'dispensers' in LEO. You need to send them a daily supply of about 1, 000kg of carbon powder. SpaceX StarShip could be used if they stick to a schedule of 1 flight per day for a few years.

Now I'm gonna do something that is not fair, but since both the cost of the dispensers and the carbon are irrelevant to the total cost I am just going to focus on the transportation costs. Now SpaceX claims they will be able to fly StarShip for 2 Million per launch. Since Elon Musk has a bad habit of being wrong with numbers, I am just gonna take this immediately to 10 million USD per flight. with about 1 flight a day for 2 years this would accumulate to about 7.5 Billion USD. Compared to probably less than 1 billion for both the dispensers and the carbon.

All numbers are rough. I am not publishing a research paper here. I just try to show that the numbers allow for more attention to the idea. Because if we can lower the temperature on earth indeed by a few degrees at the predicted cost, than we have a way to buy us time. The enormous costs of stopping the processes that cause this is clearly not happening overnight and is also, clearly costing a magnitude more. We are presently spending well in access of a trillion dollars per year on climate.

Joey

7 minutes ago, JoeyJoystick said:

Hi All,

I am Joey and I am new here. My apologies for any mistakes.

Anyway, I came to this forum to discuss exactly this. Well kinda like this.

Ever since I was a kid (teen. Big kid), I have wondered why we not 'block' the sun. Sending up a couple of sunshades sounds like a plan on the surface, but the world economy would not be able to support the transportation cost of these shades into orbit.

Then some 20 years ago we got Graphene, and the same idea crossed my mind again. But this time I dismissed it simply because even if we can get shades in place, you won't be able to keep them in place.

But than, quite recently, I got the idea to dispense powder into space. My first questions; Is it technically and economically feasible. I think the answer to both questions is yes.

After I explored my idea, I noticed that GEO-Engineering is actually a 'thing' and that quite a few people are looking into that. Including using aerosols. I even saw a study on the use of diamond powder.

But, I was looking at carbon powder. It's absorption rate and its reflective properties. My motivation here is that Graphene, being only a single atom thick, still manages to stop 2.5% off the sunlight. And this is enough to reduce the global temperature to pre-industrial levels it appears. Now considering that Graphene is only an atom thick, covering 3,000km2 with this is quite incredible I figured. It appears that when this is in powder form it has slightly better reflective properties, so this would be a win. We can use dispensers in LEO who will be loaded and slowly disperse their load into LEO. By dispersion on different latitudes, you will likely even be able to use different cooling rates at different latitudes. Depending on the altitude, the carbon powder will slowly disappear, but it will likely take a few years to have reduce the amount of carbon by half.

As to cost? You need to install 75 'dispensers' in LEO. You need to send them a daily supply of about 1, 000kg of carbon powder. SpaceX StarShip could be used if they stick to a schedule of 1 flight per day for a few years.

Now I'm gonna do something that is not fair, but since both the cost of the dispensers and the carbon are irrelevant to the total cost I am just going to focus on the transportation costs. Now SpaceX claims they will be able to fly StarShip for 2 Million per launch. Since Elon Musk has a bad habit of being wrong with numbers, I am just gonna take this immediately to 10 million USD per flight. with about 1 flight a day for 2 years this would accumulate to about 7.5 Billion USD. Compared to probably less than 1 billion for both the dispensers and the carbon.

All numbers are rough. I am not publishing a research paper here. I just try to show that the numbers allow for more attention to the idea. Because if we can lower the temperature on earth indeed by a few degrees at the predicted cost, than we have a way to buy us time. The enormous costs of stopping the processes that cause this is clearly not happening overnight and is also, clearly costing a magnitude more. We are presently spending well in access of a trillion dollars per year on climate.

Joey

I’m not quite clear whether you are proposing to introduce graphene powder into the upper atmosphere or into space. If the former it won’t stay there, due to atmospheric mixing and eventual precipitation. If the latter, i.e. into space, you would need to establish an orbiting dust cloud in effect, surrounding the sun, at some radius from it. That would need a lot of powder, it seems to me, and a lot of energy to give the dust the right orbital speed.

3 minutes ago, exchemist said:

I’m not quite clear whether you are proposing to introduce graphene powder into the upper atmosphere or into space. If the former it won’t stay there, due to atmospheric mixing and eventual precipitation. If the latter, i.e. into space, you would need to establish an orbiting dust cloud in effect, surrounding the sun, at some radius from it. That would need a lot of powder, it seems to me, and a lot of energy to give the dust the right orbital speed.

Hi exchemist,

I mean in LEO (Low Earth Orbit), and not the upper atmosphere. At very small particle sizes, it is my understanding that it will rather quickly disperse at lower altitudes because of atmospheric influences still measurable at that altitude. I do not mean in space, because that would not be feasible anymore. A shield around the sun would be significantly larger than a shield around the earth. I am talking several magnitudes. Like you said, not the way to go. But even in orbit around Earth, It would need orbital speed, and the speed is provided by the dispensers who are already in orbit. But you are correct when you say that atmospheric conditions will degrade the cloud. This rate of loss vs. altitude needs to be determined by people more clever than me to find the 'sweet spot'. You would need large amounts regardless of how you do this though. Assuming no loss, you would need 55,000 tons of powder in the first 2 years.

Joey

Just now, JoeyJoystick said:

Hi exchemist,

I mean in LEO (Low Earth Orbit), and not the upper atmosphere. At very small particle sizes, it is my understanding that it will rather quickly disperse at lower altitudes because of atmospheric influences still measurable at that altitude. I do not mean in space, because that would not be feasible anymore. A shield around the sun would be significantly larger than a shield around the earth. I am talking several magnitudes. Like you said, not the way to go. But even in orbit around Earth, It would need orbital speed, and the speed is provided by the dispensers who are already in orbit. But you are correct when you say that atmospheric conditions will degrade the cloud. This rate of loss vs. altitude needs to be determined by people more clever than me to find the 'sweet spot'. You would need large amounts regardless of how you do this though. Assuming no loss, you would need 55,000 tons of powder in the first 2 years.

Joey

1) Why graphene, not ordinary carbon ?

2) Fine to nano sized particles will filter down to ground level. What about halth risks to humand (or other species) ? Remember coal dust, silaca dust, asbestos dusk scandals ?

3) Carbon particles of any sort block the insolation by absorbtion, not reflection. So if the proposed layer is below the cloud the energy will still be confined to earth. Sunshades themselves get hot.

21 minutes ago, JoeyJoystick said:

Hi exchemist,

I mean in LEO (Low Earth Orbit), and not the upper atmosphere. At very small particle sizes, it is my understanding that it will rather quickly disperse at lower altitudes because of atmospheric influences still measurable at that altitude. I do not mean in space, because that would not be feasible anymore. A shield around the sun would be significantly larger than a shield around the earth. I am talking several magnitudes. Like you said, not the way to go. But even in orbit around Earth, It would need orbital speed, and the speed is provided by the dispensers who are already in orbit. But you are correct when you say that atmospheric conditions will degrade the cloud. This rate of loss vs. altitude needs to be determined by people more clever than me to find the 'sweet spot'. You would need large amounts regardless of how you do this though. Assuming no loss, you would need 55,000 tons of powder in the first 2 years.

Joey

OK I see. I think the difficulty with putting dust into an Earth orbit will be that you could only put the dust into one narrow band, e.g. around the equator, since to cover different latitudes would need a series of different orbital paths that would clash, unless you had a complex system with different orbits at different altitudes.

I'm not sure what orbital dynamics would do to an orbiting dust cloud. One might think that small differences in speed of individual particles would eventually make it unstable, but this is not my field so I don't know if this would actually be a problem.

3 minutes ago, studiot said:

1) Why graphene, not ordinary carbon ?

2) Fine to nano sized particles will filter down to ground level. What about halth risks to humand (or other species) ? Remember coal dust, silaca dust, asbestos dusk scandals ?

3) Carbon particles of any sort block the insolation by absorbtion, not reflection. So if the proposed layer is below the cloud the energy will still be confined to earth. Sunshades themselves get hot.

Hi Studiot,

1 - With equal size graphene is lighter because it is 2 dimensional. We struggle to manufacture graphene, but we're actually quite good at making shitty small pieces of graphene, and that is exactly what you need here. It's, to my knowledge, the cheapest form of Graphene. If not it will be when you order 50,000 tons. lol. Ok, that applies to any other thing you may wanna choose to replace Graphene as well of course.

2 - Correct. Some particles will fall down to earth. Some particles will be blown into space. Most will fall down though. I do not know if there is a better term for this than 'half-time', but I use that because it closely resembles the half-time of radioactive elements. Depending on velocity, altitude, and particle size it will take an 'x' amount of time for half of the particles to fall back to earth. There is one more significant variable in this that we can not control though. Solar flares have a tendency to hasten the downfall of particles significantly, but I know very little details about this. However, if you find an altitude at which you can release the particles where they allow you a half time of let's say 2 years, than that effectively means that you would be covering the entire planet with a layer of carbon with a thickness of a single atom. Ok, it would be the equivalent of it, but you get my drift I think. Do you think that such a small amount would harm your health? We're talking vastly different quantities compared to what coal miners inhaled in the past.

3 - Very rough numbers here. 97.5% of light passes through. 0.5% of light is reflected, and about 2% of light is absorbed. But this is not located below the clouds, but 100s of kms high. Also, yes it absorbs the heat, but instantly radiates this heat back out again. Imagine a this collecting 2.5% of the suns heat for 2 years before it falls to earth. It would be thousands of degrees C, and that is obviously not the case. Radiation.

Joey

1 hour ago, exchemist said:

OK I see. I think the difficulty with putting dust into an Earth orbit will be that you could only put the dust into one narrow band, e.g. around the equator, since to cover different latitudes would need a series of different orbital paths that would clash, unless you had a complex system with different orbits at different altitudes.

I'm not sure what orbital dynamics would do to an orbiting dust cloud. One might think that small differences in speed of individual particles would eventually make it unstable, but this is not my field so I don't know if this would actually be a problem.

Hi exchemist,

I envision dispensers in orbit. Many of them. All at different locations, such that the dispensing cloud will cover most of earth. Similar to how we presently have satellite coverage. The dispensers will 'spray' powder horizontally. With lack of atmosphere, the spread will be significant.

Furthermore, I also think we would have different densities of powder dispensed at different latitudes. And with different densities, I do not mean particle size, but how many particles are dispensed per m3. This would allow for making small variations in cooling effect depending on latitude. i.e. If today we observe more heating in the polar regions, we may want to opt for blocking more sunlight going to the Arctic by dispensing more powder at higher latitudes compared to lower latitudes.. This may actually be a very direct way to stop sea-level rise quickly.

As to orbital dynamics; Sorry, I am not that clever. What I do know is that in aerosol experiments and suggested experiments, I have never read anything about this being a problem, other than it eventually coming back down again of course.

Joey

Are you vaware that by the time you have put up 50,000 tons of powder into low earth orbit, you will actually have use something like 750,000 tons of fuel and also put up something like another 50,000 tons of rocket?

48 minutes ago, JoeyJoystick said:

Hi Studiot,

1 - With equal size graphene is lighter because it is 2 dimensional. We struggle to manufacture graphene, but we're actually quite good at making shitty small pieces of graphene, and that is exactly what you need here. It's, to my knowledge, the cheapest form of Graphene. If not it will be when you order 50,000 tons. lol. Ok, that applies to any other thing you may wanna choose to replace Graphene as well of course.

2 - Correct. Some particles will fall down to earth. Some particles will be blown into space. Most will fall down though. I do not know if there is a better term for this than 'half-time', but I use that because it closely resembles the half-time of radioactive elements. Depending on velocity, altitude, and particle size it will take an 'x' amount of time for half of the particles to fall back to earth. There is one more significant variable in this that we can not control though. Solar flares have a tendency to hasten the downfall of particles significantly, but I know very little details about this. However, if you find an altitude at which you can release the particles where they allow you a half time of let's say 2 years, than that effectively means that you would be covering the entire planet with a layer of carbon with a thickness of a single atom. Ok, it would be the equivalent of it, but you get my drift I think. Do you think that such a small amount would harm your health? We're talking vastly different quantities compared to what coal miners inhaled in the past.

3 - Very rough numbers here. 97.5% of light passes through. 0.5% of light is reflected, and about 2% of light is absorbed. But this is not located below the clouds, but 100s of kms high. Also, yes it absorbs the heat, but instantly radiates this heat back out again. Imagine a this collecting 2.5% of the suns heat for 2 years before it falls to earth. It would be thousands of degrees C, and that is obviously not the case. Radiation.

Joey

Hi exchemist,

I envision dispensers in orbit. Many of them. All at different locations, such that the dispensing cloud will cover most of earth. Similar to how we presently have satellite coverage. The dispensers will 'spray' powder horizontally. With lack of atmosphere, the spread will be significant.

Furthermore, I also think we would have different densities of powder dispensed at different latitudes. And with different densities, I do not mean particle size, but how many particles are dispensed per m3. This would allow for making small variations in cooling effect depending on latitude. i.e. If today we observe more heating in the polar regions, we may want to opt for blocking more sunlight going to the Arctic by dispensing more powder at higher latitudes compared to lower latitudes.. This may actually be a very direct way to stop sea-level rise quickly.

As to orbital dynamics; Sorry, I am not that clever. What I do know is that in aerosol experiments and suggested experiments, I have never read anything about this being a problem, other than it eventually coming back down again of course.

Joey

What I’m getting at is you can’t have an orbit at a latitude of, say, 40 deg North of the equator. It would have to be one that went from 40deg N to 40deg S and back in the course of one revolution. That’s because every orbit has to be centred on the centre of the Earth, at that is what gravity pulls towards. So if you had one like that and another that was equatorial, they would intersect, on the equator, at 2 points per revolution. So they would have to be at different altitudes to avoid colliding.

Edited June 25Jun 25 by exchemist

9 minutes ago, studiot said:

Are you vaware that by the time you have put up 50,000 tons of powder into low earth orbit, you will actually have use something like 750,000 tons of fuel and also put up something like another 50,000 tons of rocket?

Hi Studiot,

I am now. But Hydrogen and oxygen is water I believe. So that is not pollution in the long term, but it may have a small effect in thew short term. And it is short term, because the vast majority of it will be burned up in very close proximity of earth and quickly fall down again as water. I am not denying your correct, but I think the influence of this is negligible.

The rockets, of course, are re-usable. You would need quite a few of them. But hey, Elon shouted that he can launch StarShip for 2 million per trip (I calculated 10M. I struggle trusting Elon.).

Joey

Sounds expensive, and there's enough gas at LEO to cause atmospheric drag on anything moving at orbital velocity. My guess is your graphene cloud would deorbit quickly and require continual costly recharging with enormous expenditures on rocket fuel and graphene production. Money better spent on long-term solutions like improved distribution and storage of wind/solar/tidal/geothermal etc. Also, think about what happens when graphene particles deorbit and enter the troposphere where they serve as CCN, cloud condensation nuclei. Whatever cooling effect that might bring, it will also potentially destabilize the atmosphere in ways difficult to predict. Lastly, the Earth's surface is 3/4 ocean - what effects on, say, phytoplankton does thousands of tons of graphene particles have? You don't know? Nobody else does either!

3 minutes ago, exchemist said:

What I’m getting at is you can’t have an orbit at a latitude of, say, 40 deg North of the equator. It would have to be one that went from 40deg N to 40deg S and back in the course of one revolution. That’s because every orbit has to be centred on the centre of the Earth, at that is what gravity pulls towards. So if you had one like that and another that was equatorial, they would intersect, on the equator, at 2 points per revolution. So they would have to be at different altitudes to avoid colliding.

Hi exchemist,

You're correct as far as I know. But that does not change much I think. This way you can still cover all the latitudes you want. And I say 'you want' because you do not want to cover the polar areas. That would be a waste of money, time, and resources. Collisions. I know little about this, but I do know that many new satellites can change orbit when they are approaching something that could cause harm. We're not talking a swarm of satellites with the density of StarLink, but I agree it is something that would have to be looked into. But not in relation to each other. They are tied to earth, not to each other.

And I think I read somewhere I only have 5 messages on my first membership day, so I guess this is the last message I can send today... I will reply when I can.

Joey

1 minute ago, JoeyJoystick said:

Collisions. I know little about this, but I do know that many new satellites can change orbit when they are approaching something that could cause harm.

It's costly to move a satellite, and they only have so much fuel. Orbital debris is already a big problem, and a grain of sand can tear up a lot of equipment travelling thousands of miles an hour in orbit. We track everything we can, but it's not getting better since the pieces collide in orbit and create hundreds more pieces.

Here's a simulation. The red bits are debris: https://platform.leolabs.space/visualization

It seems that the disbenefits of our own private oort cloud are piling up.

It only takes a microgram of asbestos to cause cancer. How do you know that graphene is not similar?
Many cities on earth are now suffering from 'particulates' in the air seriously affecting the health of the population there.

Then there are the geological aspects of this.

It is true that sufficiently large volcanic eruptions or meteor impact can throw enough fine ash into the upper atmousphere to cause global temperature reductions.
As far as we know these temperature effect last from a few years to a decade or so.
But the erffects on the population of the planet has been more dramatic, from example exterminating the dinosaurs.

Also we are overdue for the next ice age, when we will need all the sunlight we can get.

So if we put too much material up or need to bring it down again (in a hurry) how would we do this ?

What happens if we get the right amount but then another volcano puts up more, tipping the balance into ice age ?

20 hours ago, Phi for All said:

It's costly to move a satellite, and they only have so much fuel. Orbital debris is already a big problem, and a grain of sand can tear up a lot of equipment travelling thousands of miles an hour in orbit. We track everything we can, but it's not getting better since the pieces collide in orbit and create hundreds more pieces.

Here's a simulation. The red bits are debris: https://platform.leolabs.space/visualization

Hi Phi for All,

The satellite dispenser needs to be reloaded with powder regularly. While at it, they have at least the possibility for refuelling, if required. And I am not sure if you are leaning in this direction, but I think the particle size would be too small to cause significant damage. This would need to be confirmed though.

p.s. Thanks for the link.

Joey

On 6/25/2025 at 8:02 AM, TheVat said:

Sounds expensive, and there's enough gas at LEO to cause atmospheric drag on anything moving at orbital velocity. My guess is your graphene cloud would deorbit quickly and require continual costly recharging with enormous expenditures on rocket fuel and graphene production. Money better spent on long-term solutions like improved distribution and storage of wind/solar/tidal/geothermal etc. Also, think about what happens when graphene particles deorbit and enter the troposphere where they serve as CCN, cloud condensation nuclei. Whatever cooling effect that might bring, it will also potentially destabilize the atmosphere in ways difficult to predict. Lastly, the Earth's surface is 3/4 ocean - what effects on, say, phytoplankton does thousands of tons of graphene particles have? You don't know? Nobody else does either!

@JoeyJoystick Reposting, awaiting a reply from the OP. I also wanted OP to acknowledge another potential serious consequence (the CCN uncertainty and effect of particulates on plankton I already mentioned), which is some deposition of deorbited graphene on polar ice and glaciers thus lowering their albedo and hastening melting. No matter where it orbits, air currents can take it to places one might not anticipate.

21 hours ago, studiot said:

It seems that the disbenefits of our own private oort cloud are piling up.

It only takes a microgram of asbestos to cause cancer. How do you know that graphene is not similar?
Many cities on earth are now suffering from 'particulates' in the air seriously affecting the health of the population there.

Then there are the geological aspects of this.

It is true that sufficiently large volcanic eruptions or meteor impact can throw enough fine ash into the upper atmousphere to cause global temperature reductions.
As far as we know these temperature effect last from a few years to a decade or so.
But the erffects on the population of the planet has been more dramatic, from example exterminating the dinosaurs.

Also we are overdue for the next ice age, when we will need all the sunlight we can get.

So if we put too much material up or need to bring it down again (in a hurry) how would we do this ?

What happens if we get the right amount but then another volcano puts up more, tipping the balance into ice age ?

Hi Studiot,

Yes, this should be monitored. Can be predicted to an extend as well, especially after the effects are better understood when done in practice.

For this whole idea I just wanted to see if some if the important numbers fell in the realm of possibilities. The idea grew from actually graphene. Because it gives a reference point and the numbers seem to kind match up, I have decided to use the equivalent of 1 square meter of graphene per m2 per year as the amount released around the earth.

Now let's address your health concern. 1m2 of graphene will result in 0.76mg of graphene being deposited on earth per year. Density is caused by the particles falling down and therefore being present in the air, but also resuspension. Particles already on the ground being resuspended by wind or human activity. This is by far the greatest contributor of suspended material on our scenario by several magnitudes. Generally it is accepted that 0.01 - 0.001% of particulate matter on the floor will be resuspended in the air. If we take a worse case scenario of 0.01% this would result in 76nanograms in suspension in the air. Additional suspension cause by particulate falling down is 3 magnitudes smaller and in the Pico gram range, so for practical reasons can be ignored for now. There is currently no regulation in place for carbon or graphene particulate matter. The only thing we have is WHO PM2.5 guidelines. The strictest in the world. No matter how we look at it, it appears that we stay below that by at least 3 magnitudes. Now I am not saying it is safe, but I wanted to know if it is feasible or not. I think this brings it at least in the realm of possibilities. No direct show stopper.

Yeah, you are right that this is a concern. Let's take a closer look. If we get a Toba style eruption, than we have other things to worry about. Forget climate change. lol. And it was about 75,000 years ago, so this also implies the chance of this happening tomorrow is not exactly worrisome. Let's take eruptions like Krakatoa, Pinatubo and Tambora. So these things happen like once every 75-150 years or so. If it happens we simply turn of the dispensers. All will start falling down, just like ash from the volcano. When the volcano starts, we stop. And than in time when the sky is clearing up, than we start again. But that is the simple approach. In reality it will likely be a little more complicate than that.

If an ice age arrives, than we obviously do not have global warming anymore...

There is no way to take it down in a hurry. It will need to slowly fall down by gravity. We can turn it off though. But it is not like it starts falling down when the dispensers are turned off. It starts falling down when it is being dispensed. And since you are continuously dispensing you can claim that all matter is always continuously falling down, and half of it is already halfway down at any given moment. (Sorry, in my head this makes sense, but something tells me I am not saying it clear...)

There is a different aspect about volcanos that may help illustrate that this is not quite comparable. If we take Mount Tambora for example. This was a massive eruption with between 160 and 180km3 of ejecta with an estimated 150km3 of ash, yet this cause an global temperature drop of only 0.4-0.7C. I am proposing to release something in the order of 50,000 tons per year. As opposed to km3! And think that we can achieve a temperature drop of 2C with that. I can see why people would call me crazy for that though. But hey, show me I am wrong. Please.

Joey

44 minutes ago, TheVat said:

@JoeyJoystick Reposting, awaiting a reply from the OP. I also wanted OP to acknowledge another potential serious consequence (the CCN uncertainty and effect of particulates on plankton I already mentioned), which is some deposition of deorbited graphene on polar ice and glaciers thus lowering their albedo and hastening melting. No matter where it orbits, air currents can take it to places one might not anticipate.

Hi TheVat,

My apologies for not responding earlier. Like I said in my first post, I am new. I am gonna throw it on that if you don't mind.

And thank you and all the other for all feedback. You know what, maybe it is a stupid idea. But on the surface it looks feasible. And some of things you guys have brought up, I had obviously not thought about. So I learned an awful lot in the last day again.

You wonder about the costs. It was this what motivated me to investigate further when I initially got the idea. What made me continue was the very low projected launch cost for StarShip by Elon Musk. I actually kept these numbers 5 times higher than he quoted. And the next number that motivated me what the high absorption rate of graphene. Cheap? No. Likely several hundred billion dollars. But if it does indeed work, that would be a very low price for some relief. And compared to the more than 1Trillion USD that we now spend on a yearly basis, this does not appear a show-stopper.

I was very worried about the deorbit time. And in my first post I actually made a mistake in this regard. Bottom line is that smaller particles will much quicker deaccelerate. But this also depends on altitude. However, when they reach an altitude of 10-20km, the rate of falling down slows down dramatically. From what I can now find I understand that such small particulate would decent in weeks until it reaches the atmosphere and than it would take several weeks, maybe even months until it passes through the atmosphere and land. If you increase the altitude to about 600km you can expect the matter to stay in orbit for 1-5 years. I have used 2 years in my examples. Solar activity has a dramatic, negative effect on the time to fall down. Apparently the particles are pushed towards earth. Electrostatic interference has also an effect. But I do not know anything about this. yet.

You suggest that money is better spend on solar or wind instead of this. My intention has never been to provide a solution global warming. I think I provide a solution that buys us time to install all those windmills and solar farms by actively countering the temperature rise. We pollute more? We correct more. We pollute less? We correct less. Nature has restored itself and we are not influencing the climate anymore? We stop correcting it. This just buys us time to do the things properly.

You bring up CCN. I must admit, I had not even heard of the term until now. From what I understand there is no reason to be concerned. If we use graphene powder with a size of 2-5nm it will at least be a magnitude smaller than the 50nm minimum size for them to act as CCN. In addition to this, graphene is hydrophobic. That same particle size is also the reason why it appears at first glance that the health impact will be likely be negligeable. As I outlined in an earlier post, it stay well below the few guidelines that we do have in place. Having said that, more research is required. At present there are no such safety guidelines for graphene.

The ice melting does not make sense I think. When it is cold, snow will deposit on top of the deposited graphene and therefore not be visible nor have a warming effect. If it is warm on the other hand, you will see black ice because of all the other pollutants that have been deposited over that past millennia and the additional effect of the graphene will be negligeable.

Joey

On 6/26/2025 at 5:33 PM, JoeyJoystick said:

And think that we can achieve a temperature drop of 2C with that. I can see why people would call me crazy for that though. But hey, show me I am wrong. Please.

The point is that it is your idea and your idea is really easy to feasibilty test.

In a suitable chamber, you need to introduce a disperse system at a range of concentrations (obviously including your resultant conc from the 50kT) and measure the Beer law coefficient.

Have you any evidence of this having been done ?

29 minutes ago, studiot said:

The point is that it is your idea and your idea is really easy to feasibilty test.

In a suitable chamber, you need to introduce a disperse system at a range of concentrations (obviously including your resultant conc from the 50kT) and measure the Beer law coefficient.

Have you any evidence of this having been done ?

Tried that. At first the dispersion rate depends solely on the amount of shaking, but after a few bottles you actually have to reduce the shaking because it appears to disperse more.

Joey

Just now, JoeyJoystick said:

Tried that. At first the dispersion rate depends solely on the amount of shaking, but after a few bottles you actually have to reduce the shaking because it appears to disperse more.

Joey

Thanks for the lightening quick response, but do you know what the Beer Law refers to - it is not dispersion it is transmission.

You made a prediction, where did it come from ?

On 6/25/2025 at 2:00 PM, JoeyJoystick said:

3 - Very rough numbers here. 97.5% of light passes through. 0.5% of light is reflected, and about 2% of light is absorbed. But this is not located below the clouds, but 100s of kms high. Also, yes it absorbs the heat, but instantly radiates this heat back out again. Imagine a this collecting 2.5% of the suns heat for 2 years before it falls to earth. It would be thousands of degrees C, and that is obviously not the case. Radiation.