Cover Image: November 2008 Scientific American Magazine See Inside

Geoengineering: How to Cool Earth--At a Price [Preview]

Global warming has become such an overriding emergency that some climate experts are willing to consider schemes for partly shielding the planet from the sun's rays. But no such scheme is a magic bullet















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Clouds of "Parasols" In space, as shown in this artist's conception of a sunshade, might slow the warming of our world. Image: Kevin Hand

In Brief

  • Many scientists now support serious research into “geoengineering,” deliberate actions taken to slow or reverse global warming.
  • Of the various geoengi­neering proposals, the ones that shade the earth from the sun could bring about the most immediate effects. But all of them have drawbacks and side effects that probably cannot be anticipated.
  • Pumping sulfur dioxide into the stratosphere, as volcanoes do, is the most well established way to block the sun. Other proposals call for brightening clouds over the oceans by lofting sea salt into the atmosphere and building a sunscreen in space.

When David W. Keith, a physicist and energy expert at the University of Calgary in Alberta, gives lectures these days on geoengineering, he likes to point out how old the idea is. People have been talking about deliberately altering climate to counter global warming, he says, for as long as they have been worrying about global warming itself. As early as 1965, when Al Gore was a freshman in college, a panel of distinguished environmental scientists warned President Lyndon B. Johnson that carbon dioxide (CO2) emissions from fossil fuels might cause “marked changes in climate” that “could be deleterious.” Yet the scientists did not so much as mention the possibility of reducing emissions. Instead they considered one idea: “spreading very small reflective particles” over about five million square miles of ocean, so as to bounce about 1 percent more sunlight back to space—“a wacky geoengineering solution,” Keith says, “that doesn’t even work.”

In the decades since, geoengineering ideas never died, but they did get pushed to the fringe—they were widely perceived by scientists and environmentalists alike as silly and even immoral attempts to avoid addressing the root of the problem of global warming. Three recent developments have brought them back into the mainstream.


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  1. 1. frgough 08:55 AM 10/20/08

    Ugh. Seriously, SA, you need to get off this bandwagon while you still have a little shred of credibility left. Global temperatures are cooling.

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  2. 2. iloveas97 09:19 AM 10/20/08

    why not plant more trees and stop damaging the jungle in other places of the word ? If sunlight is shaded, how about the crops we need?

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  3. 3. bethfreeman 10:31 AM 10/20/08

    This research is absolute insanity. We'd rather try to stop the sun's rays with unknown consequences for life on the planet than just stop using oil? Why not spend all the energy you're spending on this research on finding alternatives to oil and getting people to stop using it? That seems like a far more sane approach to this problem. I do realize that it's too late to stop the bulk of global warming but if we stop using oil now at least the earth might have a chance of healing within a few hundred years. You might think we would be able to "control" or "understand" the consequences of doing something like this, but history shows that that is not true. It is absolutely insane to put the future of the entire planet and all species at risk because you're not willing to stop driving your car or stop using plastic bags or figure out how to reduce global population. Oh wait, if this experiment goes wrong, you *will* figure out how to reduce global population!

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  4. 4. agenthucky in reply to frgough 10:51 AM 10/20/08

    frgough, is it not SA's job to spread the word. They aren't advocating it, they are just passing along the idea. Discussion will only help correct the problem.

    What? You think it is going to fix itself?

    I second bethfreeman, kicking oil may not fix the warming planet (and I mean warming in comparison to the last 50 years, not just looking at the last few months) but it is surely the first step!

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  5. 5. meganjonas 03:40 PM 10/20/08

    Wow! I hope one of these ideas works, cause I am going to have like 45 babies, 5 cars, and I plan to build a nice mc-mansion so far from work that I will have to drive an hour and a half one direction.

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  6. 6. Shoshin 04:12 PM 10/20/08

    ya gotta be friggin' kiddin! This story makes as much sense as that hunk of junk cover story of how someone detected a CO2 spike from the initiation of agriculture in the Mekong delta 10,000 ya. Excuse me while I get right on this...

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  7. 7. ductileironman 04:14 PM 10/20/08

    Yes, this is completely idiotic. Put up giant reflectors and then OOPS!! we ran out of sun to run our solar collectors, global plant life suffers from lower light levels, noone has the energy to get back into space to collect all the junk blocking the light from the sun, the world turns into a giant icecube and we all die. Whoever thinks this is even close to being a valid idea should be shot into space as the test material for the first round of reflective/absorptive materials to float in that orbit.

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  8. 8. Joan Larrahondo 04:43 PM 10/20/08

    Greetings. The word "geoengineering" is not new, and its definition is by no means related to global warming. Geoengineering is brief for "geotechnical engineering", the sub-discipline of Civil Engineering that studies the Earth's geomaterials (i.e., soils & rocks), their properties (e.g., mechanical, hydraulic, chemical, interface, thermal), and applications.
    Thank you.

    Joan Larrahondo
    Georgia Tech

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  9. 9. clustertim 07:48 AM 10/21/08

    Hey, if it cools things down for once, I am all for it whatever the cost!

    Jiff
    www.privacy-center.be.tc

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  10. 10. wlocke 10:39 AM 10/21/08

    Good article. Not because it is a good idea, but because we will NOT make the hard decisions required to either reverse CO2 buildup (draconian population control, full-scale coversion to nuclear electricity...) or to adapt to it (abandon New Orleans...) in a timely fashion. Technology has come to our rescue many times before (or so we as a culture believe) - why not now? Like introducing rabbits to Australia or kudzu to the U.S., the consequences may be worse than the problem. But we can only evaluate the proposals with a broad understanding of them - that, this article begins to provide.
    Would Russia be able to sue the U.S. in the World Court if increasing grain yields in their grain belt due to higher CO2 and warming were reversed by a geoengineering "solution"? We have only begun to consider the ramifications!

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  11. 11. bendjfya 11:53 AM 10/21/08

    why not make a artifical icecap .. made of a reflective light material that floats .. sew it together and cover up the sea near the poles .. much easier than creating a sheild in space and can be removed easily if it start to have adverse afects ..

    the larger the area covered the greater the cooling effect.

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  12. 12. bendjfya 11:54 AM 10/21/08

    why not make a artifical icecap .. made of a reflective light material that floats .. sew it together and cover up the sea near the poles .. much easier than creating a sheild in space and can be removed easily if it start to have adverse afects ..

    the larger the area covered the greater the cooling effect.

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  13. 13. ggreeves 04:03 PM 10/21/08

    There is significant climate engineering which can be done by adjusting the human controlled part of albedo. The reflectivity of roofs, paving, winter cover crops, and tree farm species is significant and easily controlled at very low cost.

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  14. 14. Patrick G 04:08 PM 10/21/08

    Goe-engineering may not be the final solution, but with Third World/Developing Nations populations exploding unchecked and ably aided and abetted by Aid Agencies and UN handouts funded by our Dollars/Pounds it has to be something we can at least explore in an effort to slow things down. Has anyone considered building freezer units using Liquid Nitrogen in the Arctic and Antarctic and trying to refreeze the ice caps? Bigger Ice caps reflect more heat and cool the oceans which, as I understand it, need to be reduced in temperature by around 1*C. Simply demanding that the West, who are no longer the biggest polluters, stop using hydrocarbon fuels and return to living in unheated and pre-industrial housing is not an answer. Nor is wind farming (Around 50% of the time not actually producing electricity) but reducing AirCon which uses the sea as a heat exchanger might be - particularly in the Persian Gulf where the sea temperatures have been raised by around 2*C in the last fifty years. THis is a complex problem, it needs a complex solution which may involve all of the above and not just the bits one party or another favour at the moment.

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  15. 15. Patrick G 04:22 PM 10/21/08

    Geo-engineering may not be as stupid as some commenters seem to think, but it must also be recognised as a part of the overall solution and not the only one. It is no good blaming the West for Global warming when the Developing Nations/Third World allow their populations to explode unchecked and aided and abetted by Aid Agencies and the UN using our Dollars and Pounds while blaming us for the problem. Has anyone considered installing large freezer units to maintain the Ice Packs in the Arctic and Antarctic - these could use Liquid Nitrogen - as largere Ice Sheets reflect more heat away and also cool the oceans which, as I understand it, need to be dropped in avergae temperature by around 1*C. A positive result would to reduce the use of the seas in coastal waters as a heat sink for large AirCon and power generation plants, the Persian Gulf provides a good example of the folly of doing this, with enormous ecological changes near all such installations and a rise in temperature of around 2*C in the last fifty years overall in that enclosed sea. Simply demanding an end to the use of hydrocarbon power is a pointless exercise unless there is some real investment in fuel cell technology and alternatives for propulsion of personal AND mass transport and farming wind power is not going to replace coal, gas and oil firing of power stations, much less the Greenpeace/Fiends of the Earth pet hate of nuclear power anytime soon - unless we are all prepared to go back to cooking on charcoal brazziers and living in unheated wattle and daub roundhouses with thatch for a roof. Oh, sorry, that won't work either, charcoal brazziers produce massive amounts of CO and CO2, not to mention the deforestation it would cause .....

    The problem is a very complex one which includes overpopulation of the entire earth, pollution on a massive scale by developing nations such as India and China (The scale is hidden by Greenpeac/Fiends of the Earth using a "CO2 per head" measurement) and a number of natural changes in progress. Geo-engineering may be a part of the solution, it won't be all of the solution, and we need to take a very much broader approach to the whole rather than fight over one favoured aspect or another.

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  16. 16. CT Teacher 08:01 PM 10/21/08

    I think that many of these plans are frightening in their ignorance. There is too much about the environment that we do not understand. Reducing the amount of sunlight might cool things off, but it reduces energy to plants that can act to remove CO2.
    Let's develop alternate energy sources and start pumping waste carbon (in the form of a carbohydrate like mollasses) back into old oil wells to get rid of as much carbon as we can, rather than capture CO2 that would easily escape. Find carbon-rich material to replace what has been removed from the ground. This would have a lower impact on the ecosystem if alternate energy sources are used.
    Quick fixes are dangerous. The environment has natural mechanisms to maintain a balance, and quick fixes might disrupt those mechanisms, maybe permanently.

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  17. 17. rottipwr 11:16 PM 10/23/08

    5 trillion dollars , what does a dollar have to do with a GLOBAL emergency ,money is a man made concept . I am sure if it meant the destruction of the planet we could overlook an artificial concept such as money!!!!!!!!!!!

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  18. 18. Valjean 11:21 PM 10/30/08

    The ignored infamous elephant is the hot water bottle we put under the gas comforter we keep renewing. Not the least would be indicated by the hockey stick shaped graph of the warming tracking one of the development and exploding increase of wireless communication whose energy frequencies activate, thus warms, just as those from the Sun, with no built in regular cooling periods. Radio, data transmission, TV, remotes, sensors, cell phones, trackers, locaters, internet, satellites, radar, lasers, CBs, pagers, hand helds galore, etc. all create or utilize energy frequencies that keep the atmosphere in a constant state of activity, aka: warmth. That graph will follow the warming graph shape from blade to handle and it will be totally denied even as the impact increases.

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  19. 19. Steve0703 06:03 PM 11/7/08

    We have been geo-engineering by using black asphalt for roads, on the roof of buildings. How many hundreds of square miles have we covered, increasing the conversion from light to heat.

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  20. 20. silvajmg 07:47 PM 1/2/09

    I guess Copenhagen's 2009 discussions of a post Kioto Protocol are the way to go. In the meantime it's good to have this last resource option being considered.

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  21. 21. Skywatchers 10:00 PM 1/4/09

    "They" have been "sprinkling" reflective particles and other substances for years over our heads, land and sea. Thousands of citizens have documented the jets that emit these particles, had the particles analyzed and are fully aware of this (these) program(s). These have been documented and filmed, since 1998 in America, Canada & Australia. This article seems to be 10 years too late.

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  22. 22. Skywatchers in reply to clustertim 10:13 PM 1/4/09

    Does emphasema, lung cancer mean anything to you? You will be breathing toxic material. Be careful when you say "whatever it costs"

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  23. 23. Colin den Ronden 09:47 PM 3/11/09

    I just managed to pick up a copy of your November issue and read A Sunshade for Planet Earth. There are other aspects of geoengineering we should consider. We should consider applying what we have learned about hydroponics so that we can green the deserts in the Sahara, Namibia, Australia etc. Not only would they change the reflectivity of the earth, this excess energy would be absorbed and converted to future carbon foodstuffs and fuel, in effect turning these places into carbon sinks. We should also consider changing the weather so it rains more on these places.. Surface temperatures of the oceans cause effects like El Nino. Perhaps we could lay large pipes on the seabed to pump water of different temperatures to different parts of the oceans and change these temperatures. These could also be used to pump fresh water from the melting icecaps to those desert regions. Maybe instead of looking at climate change as a disaster, we should consider what opportunities it would provide. The Antarctic supported life in the time of the dinosaurs, maybe it and Greenland can be new pieces of real estate for us. Those island nations that become submerged could be relocated to places like Australia as a symbol of brotherhood. What we gain on the roundabout we lose on the swings. Maybe we should also create carbon tables for the different types of plants and once we have ascribed values to them we could encourage people to plant the more earth-friendly plants by redirecting tax flows. Thus ranchers in the Amazon could receive money for planting trees instead of burning them. This could be monitored by satellite. We should also give town planning a rethink. We need to change zoning laws so that work is nearer home and thereby reduce transport needs. The changed standards might be seen as lowering of living standards, but would be better for the planet. The article about the Second Law of Thermodynamics deserves comment also. To me, if this law held true the universe would never have started, and as the saying goes, The proof of the pudding is in the eating. Black holes should be seen as cosmic heat sinks that would confound this law. As for the creation of chaos from order, I figured out my own maths for this when I was a teenager. Chaos and order are similar to good and evil. Evil (chaos) destroys itself and leaves good. As a recent example of this consider if Hitler had won with his madman policies. After exterminating all non-Germans he would then have exterminated all those Germans who did not agree with him in one way or another, finally leaving no one left. In a primordial system the subsystems are similar to when you are checking accounts for an error; if the error is an odd number you dont have to add all the numbers again. You just follow the rules that an odd number of odd numbers make an odd number, whereas an even number of odd numbers and an even number of even numbers make even numbers. Thus BxB=B, AxB=A, AxA=A. This can be substituted for chaos/evil-order/good. If you have three types of subsystems possible in the primordial system it means if you start of with Bs (chaos), you end up with As (order). It is not additive mathematics, more multiplicative. But 0 x 0 = 0, so it cannot be this. Mathematicians will tell you that zero dived by any number is still zero, but any number divided by zero is infinity, the opposite end of the scale. Ask them what zero divided by zero is and they will say undefined. However, I would say it can be any number you want, and thus is equivalent to an equation for creation of the universe; making something out of nothing. Just call it the God equation. Colin den Ronden

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  24. 24. Paulo Sargaço 08:01 AM 3/13/09

    Any solution like sun shading or pumping sulphur dioxide into the stratosphere runs the risk of overcompensation. Plus, as someone else said, it would only be an excuse to relax on the anti-pollution measures.

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  25. 25. GCUGreyArea 09:00 AM 3/13/09

    J. Roger P. Angel - he has just completely overcomplicated the whole idea, all you need is a spacecraft at L1 that generates clouds of dust designed to absorb the correct wavelengths, the dust should slowly dissipate due to the solar wind and can be replenished to maintain absorption at a suitable level. Why bother building high tech mirrored satellites.

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  26. 26. joel in reply to frgough 08:04 PM 4/8/09

    get real frgough, ever think of doing your homework before you comment. dimming the sun with aerosol activities already in place are contaminating soil, air and water. This is not the answer to an ever increasing problem of carbon and harmful UV.

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  27. 27. Tressor 01:52 PM 7/13/09

    Kind of reminds me of the Matrix. Here is an interesting article on geo-engineering and its possible effects:

    https://www.mindreign.com/en/mindshare/Environment/Are-Emergency-Measures-Needed-to-Save-Our-Climate-3f/sl36962306bp316cpp10pn1.html

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  28. 28. wylie coyote13 09:39 AM 7/18/09

    i have just become aware of what many call chemtrials or in other terms geoengineering....what a complete joke....it is time to wake up folks and take a look around you at what is happening...how we are controlled and manipulated. does everyone walk around with blinders on. it is time to take them off and wake up....do you think poisoning the air and earth and all the people on it is a good way to take care of the problem....i feel if we were given a chance and we really new the dire consequences of what is happening we would come together as a world or now the global community and take action together but we are not included in these gigantic ridiculous decisions and another reason i question this...who makes them anyway who gives permission for this kind of thing....we do not need to be acted upon.i feel in truth this is terrorism in america i feel as if i am being attacked on a daily basis as i watch with horror what is now filing my skies....is there anything real left in this world is it all controlled and manipulated...is there any real weather left....what are they doing in our skies......not what they say it is about....population is way out of control and since when is it a good idea to treat toxicity with more toxicity to correct the problem. with so many bad side effects as in life destroying how can it be worth it. i feel we must raise up as a people and put an end to our death by the powers that be. the risks are too great to be doing any of this and how arrogant of man to think that he can hold off what nature is doing....we could stop all of this in a day and return to a more simple way of life....small is beautiful and local seasonal organic works gepoengineering is not the answer and there is more to it than meets the eye/i.....look around folks take your blinders off and wake up to the real word......the illuminati are not our friends......check that out.....

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  29. 29. pgtruspace 04:25 PM 8/5/09

    THIS IS A STUPID IDEA!!!!

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  30. 30. algaepreneur 01:59 PM 8/27/09

    Algae is renewable, does not affect the food channel and consumes CO2. To learn about the fast-track commercialization of the algae industry, you may want to check out this website: www.nationalalgaeassociation.com.

    They are the first algae trade association in the US.

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  31. 31. algaepreneur 02:02 PM 8/27/09

    Algae is renewable, does not affect the food channel and consumes CO2. To learn about the fast-track commercialization of the algae industry, you may want to check out this website: www.nationalalgaeassociation. They are the first algae trade association in the US.

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  32. 32. Gord Davison 07:17 PM 10/6/09

    frgough;

    You are absolutly wrong. The planet is not cooling. There is global warming and it will soon run away. This is because the melting of the arctic is releasing tones of methane into the air and the reflective snow is melting. This activity makes the problem worse. It makes a positive feedback loop. In addition to this, due to the higher temperatures and warmer waters, we are getting more water vapour which is a green house gas. Soo we will develop thermal run away and the earth's temperature will settle out at about 500 degrees C.

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  33. 33. nismail 05:01 PM 10/7/09

    The CO2 greenhouse gas controversy has been a sham from the outset. It is scientifically baseless. If CO2 retains heat from sunlight, how would it allow heat escaping back out to space for planet to cool down ? It would imply a direction sensitive vapour, that is hard to believe. How does it work ?

    I call it irresponsible junk science that must be rejected ASAP.

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  34. 34. Michael Cook 08:57 PM 10/25/09

    Actually, Gord, we are slip sliding into a New Little Ice Age as we speak. The Arctic region has given us a bit of a false signal because the Bering Sea and the Arctic Ocean in the region of Alaska are in the fall-out zone of soot and dust from industrial, motorized China, over-grazed Mongolia, and the Gobi Desert that is actually getting colder and drier, because Ice Ages are periods of low moisture going up into the atmosphere.

    When soot and dust come down on ice and snow and dirty the surface, they cause those substances to melt under average sunlight much more efficiently. This has nothing to do with CO2.

    Antarctica is a good place to get away from soot and dirt effects. One of these days humans are going to wake up and smell the coffe and we will finally get an intellectually honest report of what is really going on in Antarctica, namely that the area covered by snow is actually growing and temps are actually dropping. Some really tricky reports suggesting otherwise resorted to statistical techniques like going back into the data from the 1940's and 1950's to recalculate what the average temperature would have been over the whole continent, extrapolating from a very few measuring stations that existed back then.

    By simply making up numbers to fill in gaps in the data grid some researchers have been able to re-jigger the early climate record on the continent surrounding the South Pole and make it appear to have been colder way back in the day. Ergo, if things were colder 60 years ago, temps today would appear to be warming.

    This is a disgraceful trick but it is what we get out of the fanatics who are trying to shove Cap and Trade down everyone's throats, which will cause insider green profits for some and economic disaster for regions and individuals whose fortunes depend on fossil fuels.

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  35. 35. Michael Cook 09:00 PM 10/25/09

    Also, the West Antarctic peninsula and all of the land between there and the South Pole have been "warming" only because of statistical tricks. Torture statistics enough and they will confess to anything.

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  36. 36. LauraB 02:24 PM 12/17/09


    I would like to share my interest as one of the principals of Royal Wind, we have designed an Ocean Temperature Regulatory System using our revolutionary turbines to power cold water pumps. Our system is designed to pump large amounts of cold water to the surface of the ocean to create cold water thermoclines. We believe that widespread use of our system worldwide would result in a much desired global temperature regulation and reduction. The health of our oceans and the increased carbon sequestration are linked to global sustainability. We feel that without intervention the oceans are in danger of collapse. The health of our oceans is crucial to the maintenance of oxygen levels in the atmosphere. If the oceans die, we will struggle to survive. It’s all connected: ocean health, carbon sequestration, and global temperatures. Here’s the plan:

    To install our ocean-current powered cold water pumps in strategic locations worldwide, creating cold water thermoclines, increasing the sequestration of anthropogenic carbon dioxide. Our system will also be used to build the polar icecap back to a more acceptable year-round base level which will also ensure the continued function of the thermohaline and of the North Atlantic drift. Our system will also be used to create cold water barriers to hurricanes. We can solve the Earth's problems with the right effort. We must if we plan to continue living on this Earth.


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  37. 37. debu 01:52 AM 12/21/09

    Please read my balloon inside balloon theory of twin cyclic universes of matter and antimatter on opposite entropy path producing gravitoethertons or what we call ether by annihilation of matter and antimatter at the common spherical boundary and this ether or gravitoethertons is of very high frequency and few times light speed as a result we cannot detect it but when it get focussed at centre of earth we get a hot iron core where electrons flow as electricity to produce earths magnetism. One reason of global warming is this focus of gravitoethertons and we have to tap heat from core to produce electricity and NTPC Chairman Mr. R.S.Sharma --a good friend of mine is looking into it. I also said in Michelsons experiment that drag of ether is wrong concept as it comes on Michelsons table vertically at very high speed . So the effect of ether is null but Einstein wrongly assumed light constantcy and applied lorentz to create magic of relativity --time dilation,length contraction . But I told NASA that they must abandon time machine project and PROTON COLLIDER to produce God particle will be failure as God particle or gravitoethertons are produced by annihilation of matter and antimatter and our gravity is the effect of negative pressure as reaction to expansion of our universe due to flow of gravitoethertons. But this unstable equlibrium of twin universes will result into eternal cycles of expansion and contraction giving rise to different laws and constants and suitable laws by chance may produce life on earth like planet may be in trillion upon trillion years and we are here to ponder our existance.

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  38. 38. david Nicholls 05:07 PM 1/3/10

    I think geo-engineering represents the same kind of thinking that got us into this mess. Baisically it says "Bullying nature is getting us into a hell of a mess, lets bully it even more.

    I think we need a philisophical change from bullying the "other" to seeing ourselves as part of something greater than ourselves, the ecosystem-planet.

    Seeing oneself as part of something greater than ourselves is a component of maturity, the immature try to use others and their lives get worse and worse, the mature know the more you give the more you get, we need to grow up and adopt this attitude to the awesome community we are a small but important part of.

    There is no technological substitute for a soul.

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  39. 39. debu 10:42 PM 1/4/10

    Read my balloon inside balloon theory and theory of gravitoethertons published long back and tap geothermal heat to produce electricity. Why we do not understand the rise of sea temp . which can only happen if heat is rising from molten iron core of earth and the cause is focussing of gravitoethertons at increamental rate with time . So read my theory before blinding sun.

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  40. 40. david Nicholls 04:03 PM 1/10/10

    CONSCIENTIOUSNESS THE REAL VILLAIN

    I sometimes think lazy, unproductive people do less to destroy the environment than industrious ones.

    If we could discourage conscientiousness there would be much less productivity, consumption and transportation
    of stuff.

    Also scientists and doctors would stop inventing ways for more people to be alive & healthy (putting ever more strain on the planet).

    In advanced nations we tend to think concientiousness is a virtue(I do ) but maybe this is one thing that is dangerous and stupid about it.

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  41. 41. david Nicholls 04:05 PM 1/10/10

    CONSCIENTIOUSNESS THE REAL VILLAIN

    I sometimes think lazy, unproductive people do less to destroy the environment than industrious ones.

    If we could discourage conscientiousness there would be much less productivity, consumption and transportation
    of stuff.

    Also scientists and doctors would stop inventing ways for more people to be alive & healthy (putting ever more strain on the planet).

    In advanced nations we tend to think concientiousness is a virtue(I do ) but maybe this is one thing that is dangerous and stupid about it.

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  42. 42. Ivan klasnic 11:06 AM 2/21/10

    Good concept. Whoever advocates for geoengineering should think otherwise before they can cause damages they are never going to appologise for. Anyone who's been to chemistry class knows that SO2 is not only acidic but also poisonous. Then why would one consider spraying it into the stratosphere forgetting the that may arise. What we need are solutions, permanent and not temporary. Advocating for geoengineering is postponning the problem and complicating it the more, the solution to our problem is tree plantting and not the anticipated geoengineering.

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  43. 43. Ivan klasnic 11:09 AM 2/21/10

    Good concept. Whoever advocates for geoengineering should think otherwise before they can cause damages they are never going to appologise for. Anyone who's been to chemistry class knows that SO2 is not only acidic but also poisonous. Then why would one consider spraying it into the stratosphere forgetting the that may arise. What we need are solutions, permanent and not temporary. Advocating for geoengineering is postponning the problem and complicating it the more, the solution to our problem is tree plantting and not the anticipated geoengineering.

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  44. 44. outsidethebox 09:34 PM 3/29/10

    The same "true believers" that speak with horror about geoengineering because it is a "temporary solution" are the same persons who tell us we're soon to run out of oil,coal,natural gas, etc. See a conflict there? A temporary solution may be all that's required. The problem is that geoengineering is against the one, holy and true religion of AGW. A religion that truly hates humanity. Read some of the above posts.

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  45. 45. arkside 05:58 PM 4/20/10

    Now that this issue is coming forward, it's important to look at related issues such as Global-Dimming, where atmospheric pollution blocks sunlight, causing reduced evaporation, and hence drought, and actually warms up the planet by reducing evaporative cooling.

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  46. 46. debu 05:43 AM 6/23/10

    `DO NOT DO ANYTHING . JUST WAIT FOR MORE DATAS.

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  47. 47. Kwdactyl 10:11 PM 6/29/10

    The Planet Earth and the Sun are growing in size!
    Occulation or occulting is the cause of flare's both terestrial and Solar! The sun recieves Fuel from the center of the Milky Way Galaxy . Orbiting Planets actual block energy from reaching the sun ! If you could reflect light , energy back at the sun , to compensate for Planets eclipsing the sun from the center of the Galaxy. Easy ! Right ?

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  48. 48. stopgeoengineering.com 01:32 PM 11/10/10

    It's funny reading this article post "climategate". Gore and his New World Order cronies wanted so badly to sell us on the idea of pumping multi-megatonnes of toxic particulates into our air. Now that we all know the "science" has been manipulated and exaggerated to the point it can't be trusted, and most of us realize global warming is a natural phenomenon and that dying plant matter has the biggest "carbon footprint" of all.

    The spraying continues all over the world, however, presenting a REAL threat to the environment and to humanity itself, and now the excuse is that our eyes are decieving us, we are insane, and that the "persistent contrails" we can all see, creating an artificial cloud cover over our cities are a "hoax" and do not really exist.

    We have people developing Morgellon's disease which appears to be linked to the covert spraying, and this has been identified as being self-replicating nanotech. How is contaminating our bodies, soil and water supply with aluminum, barium, strontium and nanotech "smart dust" helping save the planet?

    See the film "Endgame: Blueprint for Global Enslavement" for clues as to the real agenda behind geoengineering. I also highly recommend the documentary "What In The World Are They Spraying?" for evidence that geoengineering is already happening globally and that, if we don't put a stop to it, it will destroy our planet and our species.

    Also see the research of Dr. Hildegarde Staninger and Clifford Carnicom, for more info on the biological (Morgellon's) aspect of geoengineering.

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  49. 49. shazzan 01:21 PM 4/15/11

    Funny, S02 will cause global cooling; However its the bases of Cap&Trade to limit SO2 in order to stop global warming. I also find it funny that SA is using the term Fossil-Fuel When it was totally debunked. Oil fields have been replenishing and fuel fields are found on Titan one of Saturn's moons by the Cassini probe. How many dinosaurs died on Titan. ROFL

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  50. 50. happyinmiami 09:18 AM 7/19/12

    I think the best way to cool the earth is to add more white throughout the globe by painting all the roofs of all the buildings in the world Bright White to reflect the suns rays and brighten the earth. Also if there is intellegent life on another planet, they can spot us easier (.Smiling.)

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