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Could we use endothermic(heat absorbing) reactions to reduce hurricane strength?

  1. Sep 25, 2005 #1
    Hurricanes grow stronger over warm waters and correspondingly lose
    strength over cool waters. Hurricanes typically need an ocean
    temperature of about 80º F, 26º C, to form. This page shows the
    cooler waters following Hurricane Bonnie caused Hurricane Danielle
    following in Bonnie's wake to lose strength and dissipate:

    What Lies Beneath a Hurricane.
    http://science.nasa.gov/headlines/y2000/ast11sep_1.htm [Broken]

    According to the graphic on this page, the temperature only had to be
    reduced to about 75º F for this to occur.

    So could we cover the expected hurricane path with chemicals that
    produce a temperature reduction on mixing with water to reduce the
    ocean temperature?
    One of the most well-known chemicals with this property is ammonium
    nitrate, NH4NO3, commonly used to make fertilizer. This temperature
    reduction property also allows its use in instant cold packs.
    According to this page 14 kg of ammonium nitrate could be used to
    freeze 14 liters, 14 kg, of water:

    Re: Making ice without machinery

    The page calculates the amount of ammonium nitrate required to reduce
    the temperature from 25º C to the freezing point but then notes an
    additional amount of heat energy needs to be removed to induce the
    phase change from liquid to solid.
    If you only want to reduce the temperature from 25º C to 0º C, then
    only about 1/4 the amount of NH4NO3 needed for freezing needs to be
    used. And if you only need to cause a temperature reduction by about
    3º C, the amount can be reduced further by a factor of 1/8th. So the
    amount would be less than 1/30th that needed to induce freezing for
    this low amount of temperature reduction.
    There is a reason though why you might want to induce freezing. You
    would want to keep the temperature reduced over the covered area for
    some time so that the hurricane has time to dissipate. If the water
    were frozen at the surface, then it would require some time for this to
    melt. (BTW, the freezing point of seawater is only 2 degrees C less
    than that of fresh water so this would require only minimally more
    temperature reduction.)
    The question is how much NH4NO3 would be required for this task? For
    the freezing, about the same amount in weight as the water you wanted
    to freeze. There are a couple of options for its placement. You could
    try to freeze the surface water within the eye or you could freeze the
    water in front of the hurricanes expected path.
    I'll use an optimistic size of the eye as 10 km across, though for
    some hurricanes the eye can be 3 to 4 times this size. So it would be
    an area on the order of 100 square kilometers. How thick do you want
    the ice? That depends on how quickly you would expect it to melt at the
    26º C surrounding temperatures. I'll take as a guess for the thickness
    of 1 cm. Then this is a volume of 10,000m x 10,000m x .01m = 1,000,000
    m^3. This is 1,000,000 metric tons of water. Then it would require that
    amount in weight of NH4NO3. The worldwide production of ammonium
    nitrate is in the millions of tons per year so this would require a
    significant proportion of that. But this is within the annual
    production capacity of individual chemical plants:

    Our Products - Terra Industries Inc.

    So it is feasible if kept in storage until needed.
    For transporting this amount, there are supertankers capable of
    transporting hundreds of thousands of metric tons of crude oil. Less
    than 10 would be sufficient to transport the required amount. The
    ammonium nitrate would have to be sprayed at high speed to disperse it
    over the required area.
    It would require much less if you only wanted to decrease the
    temperature 3 degrees C, perhaps only 30,000 metric tons for the same
    volume of water. You would want this to be in very fine powder so would
    rapidly mix with the water. A problem is the temperature would rapidly
    rise from the surrounding water and air. What might be needed would be
    some method of slow release to constantly keep the temperature lowered.
    The packets containing the ammonium nitrate held within a slow release
    fabric would also have to be buoyant so that the ammonium nitrate is
    concentrated near the surface. However, the amount required might not
    wind up to be significantly less than the freezing method because the
    ammonium nitrate has to be continually supplied.
    These were estimates for covering the surface water within the eye of
    the hurricane. The eye is moving perhaps 10 km/hr and higher. At this
    speed it would leave the covered area within an hour. Would this be
    enough to dissipate the hurricane? Unknown.
    The other possibility would be to cover the expected track ahead of
    the hurricane. The front of the hurricane might be 100 km or more
    across. For this to be feasible you would need a thinner region to
    cover, say 100km by only 1 km. Then in this case the hurricane would
    pass over this region even faster. But it is unknown which method,
    covering the water within the eye or the water in front, would be more
    effective in dissipating its strength.

    Bob Clark
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Sep 25, 2005 #2


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    Well, first, I'm no meteorologist now, but cooling the water would stop the huricane from growing, but I don't know if it would dissipate it. The best thing to do would be to cool the water before the hurcane forms.

    But more importantly, I'm no biologist either but....... I think there is a reason you're not supposed to ingest the NH4NO3 found in instant cold packs...... What kind of affect do you think this will have on marine life by dissolving NH4NO3 into the water? Also, the rapid change in tempurature couldn't be good for the marine life either.
  4. Sep 25, 2005 #3


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    Yes, cooling the water would sap energy from the hurricane, but the amount of energy we're talking about is far beyond what we could affect with chemicals. Even an endothermic nuclear bomb (if such a thing existed) would have little effect.
  5. Sep 25, 2005 #4
    cool. i never thought of this. maybe we can get the airforce to do bombing runs on the next hurricane and we can drop dry ice or something.
  6. Sep 25, 2005 #5
    Dry Ice the size of Arizona I hope.
  7. Sep 25, 2005 #6
    Well here is a thought on similar lines. This idea derives from the siphoning used in OTEC. Basically set up a vast series of pumps from the bottom or near the bottom of the ocean to relatively close to the surface. When a hurricane is coming pump the cool ocean bottom water to the surface. This could sap the surface temperature enough locally to diminish hurricane strength without resorting to chemical warfare.
  8. Sep 25, 2005 #7
    chemical warfar doesn't sound good. eventually those chemicals are going to rain down onto the gulf and south/south-eastern states
  9. Sep 26, 2005 #8
    I think the solution, If any, should be done just as the hurricane is being spawned, It has less energy to wrestle with. we would have to have a good nose on the weather to spot hurricane potentials before they are spawned and take action. How good are we at spotting hurricanes before the spawning occures, Do we have an edge?
  10. Sep 26, 2005 #9
    This is a website run by a weatherman that quit his job recently for research time.

    Worth a look maybe:


    The problem is that the science neccessary to understand a good portion of this is in Russia, done by Nikola Tesla, and unavailable to most Americans without resources of U.S. Government property. But he makes several good arguements that I can't disprove or prove simply because of my location in regards to his observations.
    Heads up everyone.
  11. Sep 27, 2005 #10


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    Even if we could do so, we shouldn't.

    Yellowstone Park, the first wilderness to be set aside as a natural preserve anywhere in the world, was called a National Park in 1872, by Ulysses Grant. No one had ever tried to preserve wilderness before, they assumed it would be much easier than it proved to be.

    When Theodore Roosevelt visited the park in 1903, he saw a landscape teeming with game. There were thousands of elk, buffalo, black bear, deer, mountain lions, grizzlies, coyotes, wolves, and bighorn sheep. By that time there were rules in place to keep things the way they were. The Park Service was formed, a new bureaucracy whose sole purpose was the maintain the park in its original condition.

    Within 10 years, the teeming landscape that Roosevelt saw was gone forever. The reason for this was because of the Park rangers, they were supposed to be keeping the park in pristine condition, and had taken a series of steps that they thought were in the best interest of preserving the park.

    The Park Service mistankenly believed that elk were becoming extinct, they tried to increase the elk herds within the park by eliminating predators. To that end, they shot and poisoned all the wolves in the park, of course not intending to kill all of them. They also prohibited local Native Americans from hunting there, even though Yellowstone was a traditional hunting ground.

    Totally protected now, the elk herd population exploded and they ate so much of certain trees and grasses, that the ecology of the park began to change. The elk ate defoliated trees that the beavers used to make dams, so the beavers vanished. That was when manages found out that beavers were vital to the overall management of the region. When the beavers vanished, meadows dried up, trout and otter populations receded, soil erosion increased, park ecology changed even further.

    By the 1920s, it was clear there were way too many elk, os the rangers shot them by the thousands. The change in plant ecology seemed permanent; the old mix of trees and grasses did not return.

    It also became clear that Native American hunters had exerted a valueable ecological influence on the park lands by keeping down the numbers of elk, moose, and bison. This recognition came as a part of a general understanding that the Native Americans strongly shaped the untouched wilderness white men thought they saw.

    North American humans had exerted a huge influencee on the environment for thousands of years, by burning palins grasses, modifying forests, thinning out specific animal populations, and hunting others to extinction - capitulation to a superior species.

    The rule forbidding Native Americans from hunting was seen as a mistake, but it was just one of many that continued to be made by the Park Service. Grizzlies were protected, then killed off, Wolves were killed off, then brought back. Radio collars research was halted, then resumed. Fire prevention policies were instituted, with no understanding of the regenerative effects of fire. When the policy was reversed, thousands of acres were burned so hotly to the ground that it was sterilized, and forests did not grow back without reseeding. Rainbow trout were introduced in the 70s, that species killed off the native cutthroat species. And on and on and on and on.

    It is a history of ignorant, incompetent, intrusive interveintion, followed by disastrous attempts to repair, followed by attempts to repair damage caused by repairs. Just as dramatic as any oil spill or toxic waste dump, but in these ones there are no evil awful big corporations, or fossil fuel economy to blame. It would be the associations of learned people that worked on the project... if they messed up.

    The unforeseen effects on the environment and us (as a part of the environment) by doing anything as drastic as maneuvering a tropical cyclone are uncomprehendable.

    Of course in the (hopefully) near future, we will be able to foresee and take care of those risks, and perform some rather interesting experiments. :smile: :smile: :smile: :smile:
    Last edited: Sep 27, 2005
  12. Sep 27, 2005 #11
    I would think that Automobiles have killed more species than any other method.

    Assertive ecology is the best route to helping nature until we can move all humans to orbit, The Earth would a big green house for obiting space stations, No humans would live on Earth anymore, We would be overseers
    of an ecological resource system cultured into a utopiac world.

    If you want to help nature then I would suggest supporting our future space stations.

    One day it will be the only answer to protecting the Earths enviroment and life forms, Leave the planet altogether.
  13. Sep 27, 2005 #12


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    Staff: Mentor

    That site is pure crackpottery, Deckers. Don't bother with it.
  14. Sep 27, 2005 #13
    Nature has killed more species than any other method. 99.9..% of species which have ever existed on this planet were extinct before homo sapiens ever walked the Earth.

    Homo sapiens are a part of the biosphere. As a species we have made mistakes but like any other species we have an inherent right to compete and survive.

    Leaving the environmental ethics debate aside, the preservation of Yellowstone is an interesting dilemma itself. The volcano underneath it will probably be responsible for the greatest loss of life in recorded history sometime in the next 10,000 years or so.

    Should we begin trying to engineer it so that almost all life in this hemisphere is not obliberated sometime soon (geologically speaking)? After all a natural disaster is a natural event? Should we protect nature from the consequences of its own cycles, as we did in the Yellowstone forest and almost destroyed it in the process.

    The weatherwars site is interesting. Scott Stevens is the foremost of an outside group of "fringe researches" who think that the current weather patterns may be being influenced by deliberate means. Whether or not such efforts are scientifically possible, there are governmental and private interests actively researching it, examples include a recent US govt act (the resolution does not come to mind off hand, I will post it when I remember it).

    BtW, last I heard Tesla's research is in the hands of the US govt, it was confiscated at the time of his death.
  15. Sep 27, 2005 #14
    Could well be, but cloud seeding was attempted in years past, with sometimes disastrous results. Silver Iodide was dumped into clouds to congeal moisture and precipitate it into snow and rain. But the clouds were making hail too with the crystals.
    We had hail the size of softballs go through our roof in those days, it was frightening to me at the time. I'm still not crazy about the idea.

    That's my thought on the matter. As you say all of Tesla's work was confiscated from his lab in Colorado Springs by our government. That explosive force in Siberia that leveled trees for miles many years ago - the timing coincides with Tesla's test of a devise he claimed to be able to unleash enormous destructive power anywhere on earth. That effort precluded his ideas of manipulating weather by harnessing these same field energies.

    He was utilizing high energy Radio Frequencies not unlike Radar, but highly directed and field disruptive in nature. We did suffer a Dustbowl era near that timeframe as well. So if he had been granted credit for accomplishing this task by our Government under their directives - the Government would have had to pay for gigantic levels of damages to our own citizens possibly.

    But that doesn't mean any of it's true either. That Tesla might have determined how to do anything, still wouldn't mean Japan or Russia possess any savy able to commit such an action. Just that Ionization Energy Potential may have been manipulated in some way by Tesla.

    [corrected accidental misquote. -russ]
    Last edited by a moderator: Sep 27, 2005
  16. Sep 27, 2005 #15
    Bill before Congress "Official Title: To establish the Weather Modification Operations and Research Board, and for other purposes." Introduced (By Rep. Mark Udall [D-CO])


    At least he's facing the issue, he may recieve advisement that it's unneccessary. HAARP has been around for years now.
  17. Sep 27, 2005 #16
    I do not think HAARP and its sister installations are for weather modification. I think the military dual use is as part of SDI. Permanent heat pumps, as I proposed above, is a more likely means of weather alteration.

    Thanks for finding the bill btw, I had not yet had time to go over to the Captain's Blog.
  18. Sep 27, 2005 #17
    Where would we would get enough raw materials to build these futursitic space stations to hold all of the humans on earth? Plastic would be in great demand hoewver i have heard we only have about 30 years left of petroleum. So far we have about 9 billion people on the earth and everyday the amount of new humans born excels past the amount of humans who die. By the time we have the technology to manufacture space station this sizde i hate to think how out of control our population will be!
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