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The weather machine

The following is an edited and revised version of the talk I gave at the Global Catastrophic Risks conference that was held in conjunction with Convergence 08 (and which I reprised for Convergence). I’m posting it here because it seems to me that this is exactly the kind of thing Foresight was founded for: to examine the revolutionary impacts of readily forseeable applications of nanotechnology.

In its present form, the Weather Machine is a work of futurism, not engineering. I have done only back-of-the-envelope calculations, and my assertions about what could be built are based more on instinct and educated guesses than on any major, deep engineering analysis. Even so, as a futurist I am fairly sure that something like the weather machine will be possible within the next few decades.

The Weather Machine, Mark I

Here’s the basic idea for the machine: construct a small aerostat—a hydrogen balloon—at a guess an optimal size is somewhere between a millimeter and a centimeter in diameter. It has a very thin shell of diamond, maybe just a nanometer thick. It’s round, and it has inside it (and possibly extending outside, giving it the shape of the planet Saturn) an equatorial plane that is a mirror. If you squashed it flat, you would have a disc only a few nanometers thick. Although you could build such a balloon out of materials that we build balloons of now, it would not be economical for our purposes. Given that we can build these aerostats so that the total amount of material in one is actually very, very small, we can inflate them with hydrogen in such a way that they will float at an altitude of twenty miles or so—well into the stratosphere and above the weather and the jet streams.

Each aerostat contains a mirror, and also a control unit consisting of a radio receiver, computer, and GPS receiver. It has just barely enough power and fans or other actuators to tilt itself to a preferred orientation. That’s all it does—listens for commands on the radio, and tilts to an angle that is a function of its latitude and longitude. It’s not really a complicated machine.

Now make enough of them to cover the entire globe. For the centimeter size, you’d need about five quintillion of them. This is why nanotechnology makes a big difference. If you tried to cover the earth with something the total thickness of even a current-day party balloon, let’s say about 100 microns, you need on the order of 100 billion tonnes of material, but with the nano-engineered design, just a few nanometers thick, you only need about ten million tonnes. To compare that with the scope of current-day construction, ten million tonnes is roughly the amount of material that is used to make a hundred miles of freeway. This is an amount of material that current-day technology, much less nanotech, can handle straightforwardly.

That’s the weather machine. We have these aerostats which float twenty miles up. They have GPS and controllers and can turn themselves. That’s all there is to it. What could you do with a machine like this? The machine is essentially a programmable greenhouse gas. If you set the mirrors facing the sun, it reflects all the sunlight back. If you set them sideways, it allows the sunlight to come through, and similarly for the longwave radiation coming from the back side of the earth at night.

For comparison, the radiative forcing associated with CO2 as a greenhouse gas, as generally mentioned in the theory of global warming, is on the order of one watt per square meter. The weather machine would allow direct control of a substantial fraction of the total insolation, on the order of a kilowatt per square meter—1000 times as much. It would completely trump any natural or anthropogenic climatic forcing, and allow us to set Earth’s climate to whatever we wanted it to be.

For mere overall climate control, we’d only need to build a few tenths of a percent of a full weather machine, and the controls on the individual aerostats can be very simple. When set to let sunlight through, for example, the mirrors can be several degrees away from edge-on to the sun, and the effect would be a scattering of light (visible perhaps as a slight haziness) but no significant reduction in total insolation.

Kardashev Type I civilization

A Kardashev Type I civilization is one that controls all the energy available on a single planet. A Weather Machine would do that—our total current energy (strictly speaking, power) use, at 15 terawatts, is a completely negligible fraction of the over 100 petawatts the machine would control.

If you read the IPCC numbers on how much global warming is going to cost, the actual estimate is that over the course of the century it is going to be about 3% of the global GDP—a huge sum of money. A Weather Machine could not only prevent that, but probably double the GDP simply by regional climate control. If you could actually control the climate and tailor it, you could make land in lots of places on the earth, such as Northern Canada and Russia, as valuable as California. The economic benefit would be enormous. There is a huge amount of value to being able to control the weather. This is something that people have always wanted to do and therefore, once it becomes possible, they probably will.

The better control we have over our aerostats, the more we can do. Controlling insolation on the scale of tens or hundreds of miles would probably give us the ability to affect daily weather patterns as well as climatic averages. Given really precise control, you could enhance solar power, for example. Build an array of photovoltaics in the desert and and then program about a thousand square kilometers of aerostats above it to focus the sunlight down onto your array. Instead of needing a thousand square kilometers of solar collectors, you need only one. The main reason solar power is expensive is that it’s diffuse, so the capital costs for collecting it are high. But with 1000x concentration it should be quite economical. The concentration is more or less free because you have already built the machine to control the weather. What’s more, you have not changed the energy balance any, because you are shading all the areas that are otherwise under the thousand square kilometers. That gives your concentrated collector, in broad daylight, an energy flux that is approximately the same as a thousand nuclear reactors of a typical size. Of course, you have to cool the collectors fairly vigorously because they are not 100% efficient.

In 2029 the asteroid Apophis is going to come within the orbit of the moon, passing the earth, in what will be something of a butterfly effect incident where it is fairly difficult to predict exactly what is going to happen to it after that close encounter. Apophis will return in 2036 and we can’t say for sure whether it will strike the Earth or not. In 2029, if a highly controllable Weather Machine had been built by then, as the asteroid comes tumbling past we could focus a few petawatts of sunlight on it and give it a kick. This is probably a lot more appropriate in the case of Apophis than many other asteroids because it is going to be so close. A small kick in 2029 will have a huge result in 2036, almost certainly enough to prevent a strike if that should actually be the trajectory it’s on.

The Weather Machine, Mark II

The Mark I Weather Machine is something like nanomechanical rod logic—an gedanken experiment existence proof that a given level of technology will have a given capability. We can go a bit farther and talk about what the capability might be like given closer control of light and matter, bearing in mind this is somewhat more speculative.

Take the same aerostat, but inside put an aerogel composed of electronically switchable optical-frequency antennas—these are beginning to be looked at in the labs now under the name of nantennas. We can now tune the aerostat to be an absorber or transmitter of radiation in any desired frequency, in any desired direction (and if we’re really good, with any desired phase). It’s all solid state, with no need to control the aerostat’s physical attitude. Once we have that, the Weather Machine essentially becomes an enormous directional video screen, or with phase control, hologram.

Astronomers hated Weather Machine Mark I, but they love Mark II because it turns the entire earth into a telescope with an aperture of 8,000 miles. Mark I could zap Apophis as it flew by inside the Moon’s orbit; Mark II could zap asteroids at much greater distances, or power laser-propulsion spacecraft.

Mark II, with the ability to shift frequencies and directions independently, is powered at night. Mark I could cool the Earth by shading the sunlight on the dayside, or warm it by reflecting back the infrared that pours into the night sky. The total power going in and out is roughly the same (although more goes out from the dayside for a variety of reasons). Thus there’s plenty of power available for the nightside to do street-lighting, or show ads in the sky, or whatever you’d like. Remember that because it’s a hologram, it can have a completely different effect for each spot on the surface: my night sky can be a giant telescope, and my neighbor’s can be a giant video game.

Coming soon to a planet near you

I’m fairly certain that a Weather machine will be built sometime this century. It seems straightforwardly within the capabilities of molecular manufacturing, particularly the Mark I form. There are plenty of people worried about things like climate change or asteroid impact that it could prevent or ameliorate. It could have an enormous economic value. All of these indicate that it should be built, but the most pressing and cogent reason that it will be is likely military.

Rremember the solar power plant. What if instead of a power plant beneath this thousand square kilometers of concentrated sunlight, there were an army, fleet, or indeed a city? Another way of specifying the amount of energy that would get pumped into the area is that it would be the equivalent of exploding a one-kiloton bomb every second for as long as you wanted. A Weather Machine would be a very potent weapon, even the Mark I version. Mark II could shoot down the moons of Mars.

Even without direct attacks, whoever can control the weather on Earth is pretty much in charge here. Anyone who objects and starts rattling their sabers gets twenty years of no summer and no growing season. For that reason alone, given the technological capability of doing it, it will be done. I cannot see the US government understanding that this is possible and not doing it. In fact, there are several other governments I cannot see understanding it can be done and not doing it.

If you are a smaller government without enough conventional forces to defend yourself well while your Weather Machine is being built, I would guess that approximately 5% of one is all you would need to have a setting that was a dead man switch: if someone came and blew you up and you quit sending out the control signals, all of the aerostats would default into snowball earth mode. It would be a doomsday device. This is troubling.

Once somebody gets 5% of one built, you’re stuck listening to them. You had better start building your own first, or at least simultaneously. In fact, it seems reasonable to imagine that by later in the century there are going to be several competing clouds of these things around. Hopefully they won’t end up physically competing with each other, but that the people in charge of them will come to some negotiation. That’s going to be all the more reason for someone wanting to be in the game. You have three quintillion balloons up, and I have one quintillion, and this guy over there has two quintillion, which means we get that many votes in the weather control world government.

The ultimate implications of a Weather Machine are mind-boggling. I can’t even come close to seeing all of the implications that it will have, but I’m fairly sure that it’s possible and that it will happen. It’s worth thinking about.

10 Responses to “The weather machine”

  1. Says:

    Well, I didn’t read all the way through, but I think at the outset there might be a problem of aircraft becoming entangled in the quadrillions of tethers that make your little balloons to become aerostats.

    [An aerostat isn't necessarily a tethered balloon, but any object that can stay stationary in the air. --Josh]

  2. Says:

    “In its present form, the Weather Machine is a work of futurism, not engineering. I have done only back-of-the-envelope calculations…”

    Have you done any calculations for nanometre thick diamond at all? How would you stop the hydrogen diffusing out of the balloons, or the balloons from bursting when they get hit by a microscopic speck of dust? Seriously!?

    [See the comment below -- atomically precise diamond shouldn't have any trouble holding H2, especially at 1 Pa and 230 K, the conditions 20 miles up. Micrometeors would kill them, as would primary cosmic rays in some spots. If they killed a billion per second it'd take 30 years to get them all -- plenty of time to replenish. --Josh]

  3. Says:

    For a fraction of the cost and without exotic technology, one could achieve the similar effects with aerosols of different albedos which have a limited lifespan in the atmosphere or stratosphere (stratosphere if you wanter longer lasting)

    Also, previous commenter is right. Hdrogen will diffuse out of anything.

    [Might not be such a good idea to continuously pump millions of tons of stuff into the air that is intended to fall out into the ecosystem! --Josh]

  4. Says:

    If the objective is climate control to increase food production and population (translate consumption) then there are easier, earth-bound ways.
    If the objective is solar power as a universal power supply source, just 3 % of earth area all-wavelength absorption devices coverage in the vacumn of space would supply all of earth’s needs, at rates of 60 to 90 % less than today’s average of $9.0-12.0 cents per KWH(subsidized at 15-18 cents). And that level is enough to replace all of earth’s existing power generation plants with downstream distribution facilities, in effect leaving the facilities as “plants” but with a different mission, and allow for growth for the forseeable future, supporting up to double the earth’s existing population.
    Parenthetically, that frees up huge resources for environmental landscaping and restoration, planet-planning for species and ecosystem preservation, end-to-end recycling to preserve resources for the future, powered by processes and systems which magically become economical with virtually unlimited, low-cost power.
    I might point out that huge amounts of power are wasted even today, being absorbed by trees and buildings, plants and animals, to say nothing of the health hazards of soft tissue absorption of dangerous wavelengths.
    But, I LOVE the concept.
    I can’t wrap my head around the proposed technology, however, since more elegant, simpler solutions are in development.

  5. Says:

    There seem to be some confusion in the comments,
    First – the balloons are not tethered to the ground.
    Second – I am not sure about diamond but a single sheet of graphene (~0.34nm) has been experimentally shown not to leak hydrogen nor helium.
    Third – injecting aerosols into the upper atmosphere would likely distroy the ozone layer. The surface of the aersol allows chlorine to catalitically distroy ozone.

  6. Says:

    Sounds like a good idea to me!

  7. Oscar Harper Says:

    amazing.. look forward to see if these things end up happening

  8. Wendy Houses Cape Town Says:

    This is not the first time I’ve read abut controlling the weather as proposed in weather machine Mark 1. Not a bad idea at all, and the way things are going at the moment as far as warming our planet due to bad eco practices are concerned, the sooner the better something like this can be applied, the better. However, it still might take many years to impliment, so in the mean time we’ll have to step up our attempts to use less polluting energy and at least try to stop the damage we do.

  9. Sarah Bernheim Says:

    This machine can be useful sometimes, but not at all times. We, us humans could not control weather. With this kind of incapability, there is balance in our ecosystem. Many living things depend on weather changes, most especially plants. They grow on various environmental temperature. Of course, not all people have only one weather preference, hence it is just right that humans are not capable of controlling weather. Sine there is already a weather machine for today, it is now possible for humans to control the weather. However, its weather prediction is not that perfect. In a positive way, the machine can help in preventing serious disasters, as people will be able to have enough time to prepare themselves.

  10. Jarod Billings Says:

    I have to disagree with you Sarah. You say “us humans could not control weather”. But we already are. Just not in a positive way. And although this weather machine seems a bit out there, I think it’s just a matter of time until something very similar to this will actually exist.

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