Geo-Engineering To Solve Climate Change?

Discussion in 'Politics, Religion, Social Issues' started by King Mook Mook, Jan 13, 2010.

  1. King Mook Mook macrumors 6502

    Preface: This post is really long! Sorry, it takes a while to explain everything I wanted to explain! Please post your opinion!

    Ever since the beginning of the World people seem to have been heralding it's end. The newest end to the World is Global Warming. It brings a World with spiralling temperatures, rising sea levels and a lot of hot air (no pun intended).

    However whenever their seems to be a problem that could potentially end the World, humanity have been able to fix it or the problem fixed itself or their never was a problem in the first place.

    So why can't we solve climate change?

    To try and solve the problem, let's first look at why Copenhagen, the latest conference to try and get a multilateral agreement to reduce carbon emissions failed. It couldn't be a lack of countries as 192 countries big and small came to solve the problem. It couldn't be a lack of time as they had weeks to solve the problem and let's be honest, most of the negotiations were done outside the conference behind closed doors.

    The general consensus on what caused Copenhagen to fail, was either blaming the developing countries or the developed countries. The developing countries because they did not want to harm their growth by having to put in place costly measures to reduce CO2 emissions. Also they did not want to have to pay a lot of money for renewable energy (which at this point is quite expensive, at least more expensive then coal).

    If the blame wasn't on the developing countries it was on the developed ones. The developed countries because it appears they came to the table offering little money to the developing countries so that they can adapt to using energy that does not emit as much CO2. Also because they came to the table offering little cuts to their emissions because doing that would harm their economy and lose jobs etc.

    So based on this it appears that Copenhagen failed because of money (or, more aptly, the lack thereof) and also due to countries not wanting their economy to slow down due to them taking action on Global Warming. So the solution to Global Warming needs to be cheap, easy to implement, and not cause economies to falter.

    Luckily the (albeit temporary) fix is in. And it's cheap, easy to implement and will not slow down developing economies.

    It's Geo-Engineering.

    An example of how geo-engineering can change our temperature is Mount Pinatubo. When Mount Pinatubo erupted in 1991, it discharged more than 20 million tonnes of sulphur dioxide into the stratosphere. This acted like a layer of sunscreen reducing solar radiation on Earth. For the next two years as the haze was setting out the Earth (yes the whole Earth) cooled out by around 1 degree Fahrenheit, or .5 degrees Celsius. One volcanic eruption practically reversed the who warming of the previous 200 years.

    By calculations by scientists putting 100,000 tons of sulphur dioxide in the stratosphere per year would reverse warming in the high Arctic and reduce much of it in the Northern Hemisphere. While this may sound like a lot but relatively speaking it is a very small amount. At least 200 million tons of sulphur dioxide go into the atmosphere (note, not the stratosphere) each year. So all that would be required is one-twentith of one percent of current sulphur emissions, simply relocated to a higher point in the sky. But how do we put it higher in the sky you ask? The answer: A very long hose. Or if you are feeling slightly more technical a stratospheric shield for climate stabilisation. Here's how it works. At a base station sulphur would be burned into sulphur dioxide and then liquefied. The hose, stretching from the base station to the stratosphere would be eighteen miles long but made out of extremely light materials. The diameter is only a couple of inches so it not some huge pipe. The hose would be suspended form a series of high strength, helium filled balloons fastened to the hose at 100 to 300 yard intervals. The liquefied sulphur dioxide would be sent skyward by a series of pumps affixed to the hose at 100 year intervals. These too would be very light at around 45 pounds each. At the end of the hose a cluster of nozzles would spritz the stratosphere with a fine mist of colourless sulphur dioxide (so no the sky would not change colour). Thanks to stratospheric winds at around 100 miles per hour the spritz would wrap the earth in around ten days time. Also this is obviously not my idea, this is done by Intellectual Ventures ( and I rewrote this paragraph from SuperFreakonomics (it's a really good book. Buy it!)

    If we used geo-engineering technologies we could effectively off-put the climate changes for at least 300 - 400 years. 300 - 400 years later the current solutions will be much cheaper and much more efficient (allowing more energy to be produced in a shorter amount of time). To look at how much technology can grow in 400 years look back to 1610 and see how different the technology is then to now. I submit that geo-engineering is a temporary solution as it would be fool-hardy to continue emitting so much CO2 into our atmosphere, however as of now there are no other solutions that are economically viable and that all countries will agree to, so geo-engineering is the best solution.

    King Mook Mook
  2. Desertrat macrumors newbie

    Jul 4, 2003
    Terlingua, Texas
    Sounds kinda like a flea crawling up an elephant's leg, his mind filled with concupiscent ambition.

    What if the coolers are correct and the warmers are wrong about which way the climate is changing?

    Okay, 2" pipe, 18 miles long. Cross-sectional area is Pi.r.round; r is 1". So the area is 3.14 sq in. 37.7 cubic inches per foot. 45.8 ft of pipe per cubic foot of liquid SO2. 115 cubic feet per mile; 2,070 cubic feet total. Check my math; I'm sleepy.

    I don't know what the liquid SO2 weighs. Water is 62.4 lb/ft3. If full of water, you have about 65 tons in the pipe. That's some bodacious balloon-lift, what with pumps capable of operating against a pressure at the bottom of 65 tons per 3.14 square inches. Serious pipe, also, to handle 41,000 psi.

    I'm guessing that somebody figures on all these pumps just having to pump 300 feet, which is an operating pressure of about 130 psi--which is the pressure at my well for the water line up to my house. No big deal. But if the lights ever go out, a hard rain's gonna fall. The EPA will not be pleased. Neither will the money folks. I sure won't write the insurance on it. :D

    For sure, it'll be a case of geo-whiz...
  3. King Mook Mook thread starter macrumors 6502

    As mentioned the balloons would be very large (akin to weather balloons) and if placed properly they should be able to stand the weight of the pipe. And even if the pumps stopped working somehow, the sulphur dioxide would not just spurt out of the pipe the sulphur would stay contained.

    Also this is just one of the multiple plans, and if you look at SuperFreakonomics you will find the other plans made by people much smarter than myself.
  4. Zombie Acorn macrumors 65816

    Zombie Acorn

    Feb 2, 2009
    Toronto, Ontario
    How about we see how this pans out first before we purposely go out effecting the climate.
  5. racers macrumors regular

    Mar 24, 2009
  6. King Mook Mook thread starter macrumors 6502

    No one is suggesting we just go willy-nilly putting Sulphur Dioxide into our stratosphere. This is a last resort, if temperatures start rising it's good to have this plan B because let's be honest, it doesn't seem like plan A (reducing CO2 emissions now) isn't going to happen. So let's build these stations and have a real debate about geo-engineering so if plan A fails we have a fall back to save the planet.

    Acid rain (as all other normal types of rain) comes from the atmosphere. The suggested plan puts the sulphur dioxide into the stratosphere so there would be no danger of having acid rain or affecting any other type of rain for that matter.

    King Mook Mook
  7. Zombie Acorn macrumors 65816

    Zombie Acorn

    Feb 2, 2009
    Toronto, Ontario
    The problem with your plan is it doesn't allow government to implement more control over people, and it doesn't generate any money.
  8. King Mook Mook thread starter macrumors 6502

    Firstly I can't take credit for the plan as it was thought up by really smart people (of which I am not). And when you say it doesn't allow government to have more control over people, I'm just gonna guess you were being sarcastic.

    No, but the important thing is that it doesn't lose too much money. The system which I detailed would only around twenty million dollars with an annual operating cost of around one hundred million (much cheaper than building lots of renewable energy plants at this time). Also compare this to the 1.2 trillion dollars Nicolas Stern proposes spending each year to attack the problem.
  9. Desertrat macrumors newbie

    Jul 4, 2003
    Terlingua, Texas
    To repeat, I used water to guess at the weight. But if the electricity quits, the pressure at the bottom of the pipe would (with water) be 41,000 psi. Murphy never takes a vacation. Since SO2 is the primary ingredient of acid rain, the local area would become--to understate--"hazardous". Let's just hope that there are no endangered species within a hundred miles downwind from this project. :)

    Balloons? Ever seen one of these DEA radar balloons? Tethered? They take them down when the wind gets to 20 mph. Consider the effect of 70 mph winds in a thunderstorm.

    A calculation to be left to the student: Ignoring the weight of the pumps and electric wires to them as well as the pipe itself, figure the volume of 65 tons of air, 'cause that's what must be displaced for the balloons to support the column of liquid.

    Helium, with an Atomic Weight of 4, will leak through any container. Refilling should be an interesting exercise.

    Given the level of his understanding of practical realities, however, I can readily see Algore jumping on this bandwagon. :D:D:D
  10. King Mook Mook thread starter macrumors 6502

    Okay, sorry it's taken so long for me to respond... things to do etc. Well first let's start with it's density. In your calculations you used the density of water in leiu of it's actual density. I've looked it up and after some calculations I have discovered it's density is 0.1635 lb/ft3. This is much much much lighter than water which is as you said 62.4 lb/ft3. So if we use the actual number in your calculations the actual psi would be much smaller as the weight is much smaller hence less force is required. Also even if the pumps stop as mentioned before then it is not going to spill out in to the atmosphere as you said rather it will continue down the pipe causing no damage to the atmosphere or anything else for that matter.

    As I said previously the sulphur dioxide is not going to miraculously spill out of the pipe into the atmosphere so would not cause acid rain of any kind. Also as the actual weight is much smaller than what you calculated what you have said about the weight is moot. As for the balloons I believe they are high strength (preventing leak out and when they do need to be replace this could be achieved with a number of aeroplanes, helicopters etc.) Remember while this is one of many plans, the main point I am focusing on is will it work. The schematics can be worked out later and as you seem to have no objection to the idea of putting sulphur dioxide into the atmosphere, then I have achived my goal.

    King Mook Mook

    P.S. I totally agree with your last statement in regards to Al... :D
  11. Desertrat macrumors newbie

    Jul 4, 2003
    Terlingua, Texas
    Google is your friend:

    "At room temperature, sulfur dioxide is a nonflammable, colorless gas with a very strong, pungent odor. Most people can smell sulfur dioxide at levels of 0.3 to 1 ppm. It is handled and transported as a liquefied compressed gas. It easily dissolves in water. The liquid is heavier than water."

    Heavier than water. Oops! :)
  12. mcrain macrumors 68000


    Feb 8, 2002
    I don't want to get into global warming or whether it's real, but there have been discussions about the possible causes (if it's real - I think it is).

    I have heard people say it's not the cars! It's not the humans! It's not us! It's natural warming! It's cold today, therefore it's actually getting colder!

    There is some science to suggest that CO2 and other greenhouse gases are increasing in our atmosphere.

    The amount of greenhouse gases being put into the environment from cows is enormous! Almost 1/2 of the gases. Natural? There are environmentalists who are giving up meat!

    I point that out because cars, burning fossil fuels, and yes, eating food, have an effect on our environment. Yes, we've cut down huge chunks of rainforest, but we've also created huge amounts of plant matter where we farm. I have no idea what the overall effect is, I'm not an environmental scientist, but I see that there are things we as a species have done that could affect our planet.

    If there is a way to reverse bad trends that builds our economy, I'm all for them. Sticking with oil and sending money to the middle east and to big-oil companies, and doing nothing about what MIGHT be happening seems short sighted and I don't see how that helps my country.
  13. Desertrat macrumors newbie

    Jul 4, 2003
    Terlingua, Texas
    mccrain, few things are ever "established" in science. There is always new data--or, at least, the search for new data should never stop.


    Warming causes the release of CO2; that's a physical fact. The thesis is that CO2 is not causative of warming. Support for the thesis of the article comes from NOAA data that the oceans are cooling, very slightly. Note that there have been numerous reports of corrections in compilations of data for air temperatures, all having been revised downwards.

    As far as methane release, 6.7 billion people do pretty good at that. Along with elephants, deer, elk, buffalo...

    Cows are vegetarians, right? So maybe Vegans release more methane than us meat-eaters. :D

    So if the article is correct, the idea of SO2 as some sort of trigger to reduce warming would only worsen the onset of serious cooling. That would be bad for grain production, worldwide. Warming would improve that production in, e.g., Canada and Russia.

    The whole issue of warming vs. cooling has become one of religious faith, not science. Might as well just choose up sides and have a competition of smelling armpits.
  14. mcrain macrumors 68000


    Feb 8, 2002
    1. My name is mcrain. M as in my first name, the rest is my last name. I'm not McRain, I'm not McCrain, just MCrain.

    2. It's a bit of an overstatement that warming vs. cooling has become one of regious faith. There are scientists and data and research involved. You may disagree with the findings or the theories, but it's not faith. Unfortunately, the people who most oppose the theory that we as a species are affecting our planet want you to think it's faith, so that you can dismiss the science of it as nothing more than something made up (akin to religion).
  15. Desertrat macrumors newbie

    Jul 4, 2003
    Terlingua, Texas
    Sorry about the typo.

    "Religious faith" does accurately describe the behavior of way too many of those who believe that the climate change is one of warming. I have no problem with scientists' conclusions which appear to be objective. However, there is conflicting data, and the "warmers" behavior is as though they're seeing/hearing sacrilege and heresy.

    Intriguingly, Walter Williams speaks to this very behavior:

    'Political commentator Henry Louis Mencken (1880-1956) warned that "The whole aim of practical politics is to keep the populace alarmed — and hence clamorous to be led to safety — by menacing it with an endless series of hobgoblins, all of them imaginary." That's the political goal of the global warmers.'

    My own problem as a reasonably rational and competent professional engineer is my doubt as to any efficacy of the proposed solutions which come from the politicians--or from groups who think the OP's SO2 pipe have validity.
  16. NT1440 macrumors G4


    May 18, 2008
    Food for thought, what do you think of our wars on terror, drugs, etc.....
  17. Peterkro macrumors 68020


    Aug 17, 2004
    Communard de Londres
    The Socialists and Communists are coming for you,hide quick they'll have your freedoms away.;)
  18. Eraserhead macrumors G4


    Nov 3, 2005
    The difference between those and climate change is that prominent scientists don't publish things in peer reviewed journals discussing how serious the threat from terror, drugs etc is and what evidence they have to back that case up.
  19. NT1440 macrumors G4


    May 18, 2008
    Exactly, as far as i'm concerned climate change poses a far bigger threat in far more ways than either of the other two conflicts.

    No I don't think that a sudden event will kill us all, but we can either change what we are doing now, or hope that in the future we can deal with changes to our populated areas and the climate our food supply needs to survive.
  20. King Mook Mook thread starter macrumors 6502

    Sorry you're right! My mistake... I think I must have done a wrong calculation somewhere... anyhow it's actual weight is 91.37 lb/ft3. And also in regard to your previous comments about the balloons, they are not going to fly around freeform they will be attached to the pipe at multiple points. Hence the wind will not make them fly around as they will be essentially completely attached to the pipe.

    And also allow me to clarify the system. It will not cool the whole world. In actuality it's main effect will be on the polls, so though the rest of the Earth will cool slightly from this blanket, the polls will cool more than the rest of the Earth. And if this is true about cooling then they system can be stopped at very short notice and everything will equalise out in a year at most. So this system will not have a permanent effect. And also in regards to the pumps... They will be at every one hundred metres and will be essentially the same as swimming pool pumps and this allows each pump to have a smaller overall job (less pressure on each of the pumps). This also means that if a few of them fail the mission itself wouldn't. This is much more efficient and cheaper than putting one huge-ass pump at the bottom of the pipe... Any questions?

    King Mook Mook

    P.S. Here is another one of the proposed systems to get the SO2 into the stratosphere. Allow me to reiterate that this affect of SO2 on cooling is well documented and is proven in the example of Mount Pinatubo exploding and putting a amount of SO2 into the stratosphere and hence cooling the area slightly. The cooling effects of Mount Pinatubo were exhaustively studied and remain unchallenged. In addition the stratospheric shield could also shield out damaging UV rays.

    Another idea, which may seem less repugnant to some of you (Desertrat cough, cough) is simply extending the smoke stacks at some strategically located power plants. This plan is probably more appealing to some as it simply repurposes existing pollution without creating more. While it may sound difficult to change smoke stacks from going several hundred feet into the air to 18 miles into the stratosphere again there is a solution. The solution is essentially attaching a long, skinny hot-air balloon to an existing smokestack, creating a channel that lets the hot sulphur gases rise by their own buoyancy into the stratosphere.

    And even if that is too repugnant than there is another completely different plan: A sky of beautiful blue clouds. Man-made clouds - the contrails of a jet for example - have a cooling effect. After the September 11 attacks all commercial flights in the USA were grounded for three days. Using data from more than four thousand weather stations around the country found that the sudden absence of contrails accounted for a rise in temperature of nearly 2 degrees Fahrenheit or 1.1 degrees Celsius. There are three ingredients for the creation of clouds ascending air, water vapour and solid particles known as cloud formation nuclei. When planes fly, particles in the exhaust plum serve as the nuclei. Over land masses dust particles do the job. But there are far fewer cloud-friendly nuclei over the World's oceans. As a result more sunlight reaches the Earth's surface. The ocean as it is dark is particularly good at absorbing the Sun's heat. By IV's calculations an increase of just 12 percent of the reflectivity of oceanic clouds would cool the Earth enough to counteract even a doubling of the Earth's CO2 emissions. The solution: use the Ocean itself to make more clouds. As it happens, the salt-rich spray from seawater creates great nuclei for cloud formation. All you have to do it get the spray into the air, several feet above the ocean's surface. From there it naturally lofts upwards to the altitude where clouds form. There are multiple ways to make this happen. The current favourite is a fleet of wind-powered fibreglass boats with underground turbines that produce enough thrust to kick up a steady stream of spray. Because there is no engine there is no pollution. The volume of spray could be easily adjustable. Nor would the clouds reach land, where sunshine is so important to agriculture. The estimated price tag: $50 million for the first prototypes and then a few billion for a fleet of vessels.

    (Again sorry for the long post)
  21. Zombie Acorn macrumors 65816

    Zombie Acorn

    Feb 2, 2009
    Toronto, Ontario
    In a world as random and diverse as ours have you not thought that perhpaps the earth can compensate for these situations? I imagine we will be trending towards a cooling period, if we are releasing more green house gases then ever that doesn't make any sense. If the world is warming its not happening very fast, 25 degrees feels like a nice day here after having 5 degree weather for a month (which is mostly unprecidented in my time)
  22. Desertrat macrumors newbie

    Jul 4, 2003
    Terlingua, Texas
    Balloons or no balloons, how's this thing gonna stay in place? Even a ten-mph breeze will lay a tethered balloon over some 30 degrees or more from the vertical. Eighteen miles up means some of that tube is going to be in the jet stream with its several-hundred mph winds. Seems to me that when you get about five miles up, that tube is gonna make a ninety-degree bend in the downwind direction. You can go to the NOAA website and browse for "Winds Aloft" in the section on information for pilots.

    Ever sailed a boat? Those balloons will be just like sails insofar as side loads on the pipe. Cross-sectional area times the drag coefficient times the pressure from the wind = a bunch of stress on the pipe.

    91 pounds per cubic foot? If the electricity ever fails, the pressure at the bottom of the pipe will be not 41,000 psi but around 60,000 psi. You can't avoid leak-back. You're gonna have SO2 splattered all over the place. About the only pipe material which could cope with that sort of problem would have to be the extremely-rare Unobtanium.
  23. King Mook Mook thread starter macrumors 6502

    Did you read the part about the boats? In the boats idea there would be no balloons involved. None. Zero. This plan is just about spraying the water a couple of feet into the air. The rest happens naturally. No balloons required. This process is what happens when you use a boat in the ocean or anywhere where there is water for that matter.

    King Mook Mook
  24. King Mook Mook thread starter macrumors 6502

    Another preface: Sorry this is also long, but is well worth the read and I wanted to give Desertrat all of the technical details...

    In regards to the wind some research... As you mentioned winds at altitude are strong, often blow in different directions at different altitudes, and can change speed and direction rapidly. The need to deal with the static and dynamic forces imposed by wind will greatly influence the design of the hose’s aerial support.
    The existence of winds prevent the question of top-hung vs. distributed support from being the open-and-shut case it would otherwise be. The most efficient way structurally to help a long, thin object such as the hose resist sideways deflection by the wind is to draw it taut—exactly what a giant balloon at the top would do. Moreover, the strongest and most variable winds do not occur in the stratosphere, but at inter- mediate altitudes of around 10 kilometers (33,000 feet)— altitudes where one might distribute smaller support balloons. Lofting balloons in the windiest part of the atmosphere will expose the system to more wind stress.
    Wind speeds generally increase in altitude, reaching values around 60 m/s at heights of 10 to 15 kilometers. When convolved with the atmospheric density profile, the dynamic pressures generated by the wind peak at roughly 1,000 Pa in the vicinity of 10 km altitude.
    The wind pushes both the balloons and the hose itself. These should be thus designed to minimize drag and to present the smallest cross-section to the wind achievable (particularly for segments near 10 km altitude, where the wind forces are highest).
    The balloons pose the greater challenge because of their larger lateral area: a single spherical balloon 35 meters in diam- eter presents about 1,000 m2 of area to the wind, for example, which is about the same lateral area as the entire length of a hose 3 centimeters wide and 30 km long. Omitting balloons from the hose in the region around 10 km altitude would reduce the dynamic pressure on the system. But if the hose is denuded of balloons in its middle, the balloons at higher altitudes must be correspondingly larger.
    To illustrate the trade-off, let’s compare two designs for supporting a StratoShield that includes a hose 3 cm in diameter, pumped solely from the ground. For safety, let’s assume the balloons must support the full 50 tons of the lofted structure plus the SO2 payload, not just the weight of the empty hose.
    The first design balances lift and weight locally, as they vary along the hose, by placing balloons of appropriate size every half kilometer. The balloons range in diameter from 15 meters at the base to 56 meters at the top. Altogether, the balloons present an aggregate lateral area of 30,000 m2 to the wind—30 times the area of the hose itself. When convolved with the dynamic wind pressure, the aggregate side force (for a drag coefficient of 1) is 3.3 MNwt, which is more than six times the weight of the hose.
    The second design balances lift and weight globally, by plac- ing balloons only near the top of the hose, at a spacing of a half kilometer between the altitudes of 20 and 30 km. The balloons in this design are larger, ranging in diameter from 50 meters to 85 meters. Altogether, their aggregate lateral area is 45,000 m2, 50% larger than in the first case. When convolved with the dynamic wind pressure, however, the aggregate side force (again for a unit drag coefficient) is only 2.5 MNwt, about one quarter lower than in the first design. The side force is still much greater than the weight of the hose, however. Clearly we must find some way to drastically reduce the wind load.
    One redeeming feature of wind forces is that they can pro- vide aerodynamic lift as well as drag. We could take advantage of this by using kites or other lifting airfoils to help support the hose. Although they wouldn’t function all the time, they would provide lift at precisely the times it is most needed—when the wind is severe and pushing the hose sideways.
    An even better solution may be to use buoyant lifting bodies, such as elongated balloons shaped like aerodynamic blimps rather than squat pumpkins. The balloons themselves can then combine the functions of static and dynamic lift.
    This approach offers three major advantages. First, an elon- gated shape presents a much smaller frontal area to the wind for any given interior volume. Second, and even more important, is a reduction to the drag coefficient: for a typical blimp this is about 0.05, 1/20th that of a pumpkin-shaped balloon. Finally, blimps can be designed to generate aerodynamic lift
    that greatly exceeds the drag force. JP Aerospace has designed large V-shaped blimps that reportedly can generate 20 times as much lift force as the drag imposed by incident wind. The company has even constructed prototypes. Although a high ratio of lift to drag doesn’t actually reduce the lateral force imposed by the wind, it would increase the hose tension, thereby reducing the deflection caused by the wind.
    The one clear disadvantage of using blimp-like balloons is that they are less structurally efficient than pumpkin-shaped designs. That is, they have more wall mass per unit of buoyant lift, so they must be larger and made from more envelope material. These are affordable penalties, however, particularly since the gains in aerodynamic lift more than offset the losses in buoyancy.
    We can similarly reduce the drag coefficient of the hose by giving it a streamlined shape or by surrounding it with a low-mass aerodynamic sheath. In either case, the wind will automatically twist the hose into the proper, drag-minimizing, orientation.
    It seems clear that sensible use of well understood strategies for producing aerodynamic lift and reducing aerodynamic drag can enable a StratoShield system to tolerate wind forces with only modest (albeit highly dynamic) deflection of the hose.

    I think I have given you the wrong impression of what these 'balloons' will look like. Take a look at the gallery to see their design. I have already pointed out the part about how wind would not cause major issues. Also refilling could easily be accomplished be assigning time each month to take down the system and refill the balloons and then put it up again. Extra SO2 could be put into the stratosphere to compensate for the off-time.

    I've been doing doing some research and here is how you would pump it.. 100,000 tons a year, when pumped continuously through a hose, amounts to just 3.2 kilograms per second and, at a liquid SO2 density of 1.46 grams per cubic centimeter, a mere 34 gallons (150 liters) per minute. A garden hose with a 3⁄4-inch inner diameter can deliver liquid that fast.
    It takes quite a bit of energy to lift material into the strato- sphere: about 30 trillion Joules of potential energy, in fact, to lift 100,000 tons to a height of 30 kilometers. If the work is spread out over the course of a year, however, that energy translates to a required power of just 1,000 kilowatts. Inefficiencies and other practical considerations will increase this amount, possibly by several times; nonetheless, the power levels are not daunting by industrial standards.
    To pump 34 gallons a minute up a 30-kilometer-long hose, the system must overcome both the gravitational head and the flow resistance. The gravitational head, which is simply another way of talking about the potential energy considered previously, would amount to a pressure of 4,300 bar (62,000 p.s.i.) if the liquid has a constant density of 1.46 g/cm3—not taking into account the small attenuation in the strength of gravity with increasing altitude.
    The density of the SO2 does not remain constant during its journey through the hose, however. That transit takes enough time that at any point in length of the hose, the temperature of the liquid inside the hose is not too far from the temperature of the air outside it, although friction from the flow will impart some heat to the fluid. Air temperature drops with altitude, and so will the temperature of the SO2; the density of the liquid thus increases with altitude. The magnitude of the density change will vary depending on the site of the StratoShield as well as the season and time of day, but we
    can use the thermal profile of the Standard Atmosphere to
    estimate a typical value: between 1.40 g/cm3 and 1.57 g/cm3. This density range from bottom to top produces an overall gravitational head of 4,520 bar. There isn’t much we can do about gravity except fight it with pumping power.
    We have more control over the second kind of impediment, flow resistance. This pressure arises from drag forces imposed on the fluid by the walls of the pipe. By selecting the diameter of the hose and other design characteristics, we can choose whether the flow resistance pressure is much greater than the gravitational head or much less than it. A lower flow resistance might seem always preferable, but it comes at a price: a larger diameter hose, which means more mass for the balloons to support.
    The weight of both the hose itself and the fluid it contains increase quickly as hose diameter expands. Consider two designs, one using a hose with a diameter of 5⁄8 inch (1.6 cm), the other a hose 11⁄2 inches (3.8 cm) in diameter. The 5⁄8-inch hose has a cross-sectional area of 1.98 cm2, which means that the flow velocity at the ground must be 11.4 m/s to achieve the required 34 gallons per minute delivery rate. (The flow velocity for this hose drops to 10.2 m/s at higher altitudes, due to cooling of the SO2.)
    To calculate the resulting flow resistance, we need to factor in the flow’s Reynolds number and also the effect of pipe roughness. We’ll assume a wall roughness of 1⁄2 mil (13 micron). The Reynolds number, like density, is a function of temperature and thus altitude. It changes along the hose by more than a factor of two—from 320,000 to 810,000—due to the temperature-induced gradients in density, viscosity, and velocity.
    Fortunately, this variation in the Reynolds number has very little effect. The flow resistance remains essentially constant along the hose, ranging from 1,000 to 1,100 bar/km. The total flow-induced pressure head for the 5⁄8-inch hose is thus 30,800 bar, much larger than the 4,500 bar gravitational head. For a 5⁄8-inch hose, drag forces thus largely determine our pumping power.
    In contrast, a 11⁄2-inch hose can deliver the payload at a flow rate under 2 m/s, which generates a markedly smaller flow resistance of just 360 bar. The price for this huge reduction in pumping requirements is, of course, the need to generate more lift to support a heavier hose. The SO2 alone in the 5⁄8-inch hose weighs 9.1 tons, whereas the liquid in the 11⁄2-inch hose comes to a whopping 52.5 tons. The larger-bore hose will also weigh more than the thin hose, of course, but that difference is at least partially offset by the need to install more pumps (and electri- cal cable to run them) along the length of the thin hose. The choice of the optimum hose diameter thus requires a complex set of design trade-offs; one cannot simply peg the flow resis- tance to some percentage of the gravitational pressure head.

    I hope this answers your questions,
    King Mook Mook

    P.S. The balloons (or blimps really) have been tested (photos are included in the gallery).

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  25. Desertrat macrumors newbie

    Jul 4, 2003
    Terlingua, Texas
    Pretty picture. But it ignores the reality of the effect of the jet stream. Think back to all those Weather Channel videos of hurricanes. The worst you saw is less wind than the jet stream.

    "3.2 kilograms per second". That's easy to work out in terms of voltage and current draw. From there you go to the necessary diameter of the copper conductor. They seem overly optimistic as to that weight.

    Air density declines with altitude, so the higher-up balloons gotta be big mothers. And, as I asked earlier, how do you add make-up Helium to the balloons after they leak down?

    Don't forget aviation warning lights. :) And the protest against a Restricte Area for flight, within some number of miles. Heh: The EIS oughta be a doozy, given today's attitude against poisons in public.

    Still, I want to know what sort of flexible material can deal with the pressure of an 18-mile-high liquid. Pressure is force per unit area, and it will be the same for a small-diameter tube as for a large-diameter tube. And there has yet to be any system powered by electricity which has never had a blackout. There has yet to be a valve for one-way flow which doesn't have at least some miniscule leak-back after the flowing liquid does some slight erosion of the mating surfaces. Flowing liquids erode, which is why we have the Grand Canyon.

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