Hurricane characterisitcs

Discussion in 'Earth Science' started by kingwinner, Nov 12, 2005.

  1. valich Registered Senior Member

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    <img src=http://en.wikipedia.org/wiki/Image:Hurricane_profile_graphic.gif>
    Hurricanes form when the energy released by the condensation of moisture in rising air causes a positive feedback loop. The air heats up, rising further, which leads to more condensation. The air flowing out of the top of this “chimney” drops towards the ground, forming powerful winds.

    "A cyclone [or a hurricane as they are called in the Atlantic] is a large, rotating system of clouds, wind and thunderstorm activity. Its primary energy source is the release of the heat of condensation from water vapor condensing at high altitudes, the heat ultimately derived from the sun. Therefore, a tropical cyclone can be thought of as a giant vertical heat engine supported by mechanics driven by physical forces such as the orbital revolution and gravity of the Earth. Continued condensation leads to higher winds, continued evaporation, and continued condensation, feeding back into itself. This gives rise to factors that give the system enough energy to be self-sufficient and cause a positive feedback loop where it can draw more energy as long as the source of heat, warm water, remains. Factors such as a continued lack of equilibrium in air mass distribution would also give supporting energy to the cyclone. The orbital revolution of the Earth causes the system to spin, giving it a cyclone characteristic and affecting the trajectory of the storm.

    The factors to form a tropical cyclone include a pre-existing weather disturbance, warm tropical oceans, moisture, and relatively light winds aloft. If the right conditions persist and allow it to create a feedback loop by maximizing the energy intake possible, for example, such as high winds to increase the rate of evaporation, they can combine to produce the violent winds, incredible waves, torrential rains, and floods associated with this phenomenon.

    Condensation as a driving force is what primarily distinguishes tropical cyclones from other meteorological phenomena, and because this is strongest in a tropical climate, this defines the initial domain of the tropical cyclone. By contrast, mid-latitude cyclones, for example, draw their energy mostly from pre-existing horizontal temperature gradients in the atmosphere. In order to continue to drive its heat engine, a tropical cyclone must remain over warm water, which provides the atmospheric moisture needed. The condensation of this moisture is driven by the high winds and reduced atmospheric pressure in the storm, resulting in a sustaining cycle. As a result, when a tropical cyclone passes over land, its strength diminishes rapidly."

    http://en.wikipedia.org/wiki/Hurricanes
     
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  3. valich Registered Senior Member

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    [/IMG]<img src=http://en.wikipedia.org/wiki/Image:Hurricane_profile_graphic.gif>
     
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  5. valich Registered Senior Member

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    <img src=http://upload.wikimedia.org/wikipedia/commons/a/a2/Hurricane_profile_graphic.gif>
     
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  7. Light Registered Senior Member

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    Hello Valich,

    I believe it's finally time for me to appear back in this thread again. Everything you've posted is good, solid science. Pretty much everything your correspondent (URI) has posted is pure junk and conjecture on his part. He appears to be out to set the world on edge with his "theories" of paramagnetism, E, H, and B-field nonsense. He really has nothing to stand on anywhere in that. (He's also the same crackpot who did certain "calculations" about moon landings and the black hole at the center of the galaxy. And when asked to show his calculations, he ran like a scared rabbit!)

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    So don't take anything he ever says as serious. I took six quarters of meteorology (though it wasn't at all related to either of my degrees, just something I've always been interested in) and also continue today to stay on top of the latest research and developments.

    Yes, both hurricanes and tornadoes are heat-driven. And I believe at this point you have a good grip on hurricanes so I'll talk just a bit about tornadoes.

    One piece of information you came across and posted (downdrafts at the rear of supercells, etc.) came very close to mentioning what is currently accepted as the conditions that actually spawn one. In addition to the downdraft which can acquire a twisting motion, there is also another mechanism which has been recognized. In any thunderstorm that produces supercells, there is always a cold front overriding a warm front. This always produces a turbulence at the interface. Initially, that turbulence starts out as a horizontally rotating mass of air and a great deal of energy is released from the condensation of the warm, moist air. And that's exactly what feeds and produces the supercell itself.

    Here is the next step. If there is sufficient turbulence and it releases sufficient energy at the point the downdraft becomes strong enough, the horizontally rotating air will be pulled downward and a "funnel cloud" may begin to appear at a slight vertical angle. This is what shows up on doppler radar as a "hook" and indicates that a tornado may be forming. And it's precisely at that point under today's guidelines that the National Weather Service will issue an alert.

    If the warm/cool interface continues to release enough energy and the downdraft grows strong enough, the funnel cloud will continue to drop lower and lower and an actual tornado may form. It's really quite a grand balancing act that has to occur just so or the tornado will fail to fully form and the rotating "log" of air can be easily drawn back into the full (or near) horizontal orientation. And we should be very thankful that it requires such a precise balancing act to produce them - otherwise they would be much more frequent.

    I now return you to your regularly scheduled program (which is your dealings with the weather-wacko URI.)

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  8. URI IMU Registered Senior Member

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    from >> wacko URI.>>

    This diagram is deficient in that there is a spin over and above what has been shown.

    The whole cell spins horizontally... a tangential vector plus there is an axial circulation vector... a torus, contained in a diamagnetic ring, and a resultant that maintains the integrity ( shape, structure ) to counter the normal inertial path outwards due to the spin.

    3 vectors, a Poynting crossed power vector and resultant is produced...... The diamagnetic shielding allows the spin to increase to an equilibrium value depending upon friction.
    The B vector is axial (vertical circulation), the E vector is tangential (horizontal circulation), while the orthogonal resultant directed towards the centre (radial force) contains the whole torus.



    Mr Light please show the mechanics of your descriptions..... give us some meat to your alleged process.
     
  9. Light Registered Senior Member

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    MY process???? Hardly! What I described is the most current thinking (as of six months ago, anyway). And I'll show you nothing until you provide those "calculations" that you claimed to have made - and then ran like a scared kid when a few of us asked you for them! Still waiting...
     
  10. URI IMU Registered Senior Member

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    729
    I could calculate the Poynting vector and the 'gravity' that contains the spin system, if I knew the spin rate at r from the centre.

    I will assume a tangential spin velocity of 300 km/hr at 100 km from the centre.

    A radial acceleration about 0.07 m/sec^2 would "contain" the hurricane.
     
  11. URI IMU Registered Senior Member

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    >> like a scared kid when a few of us asked you for them!

    I don't respond to such requests.... I know you would have no idea what my calculations mean. << And I'll show you nothing >>> good idea.

    So cyas

    Believe your <<< most current thinking >>

    good luck.....
     
  12. Light Registered Senior Member

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    Yep, just like before. Run away when your bluff is called. We're all getting to know what a fake you really are. "Worthless" comes to mind...

    Bye-bye! (Good riddance!)
     
  13. valich Registered Senior Member

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    URI: "This diagram is deficient in that there is a spin over and above what has been shown."

    I am not totally discounting your theory, but I believe that the explanation given in Wikipedia and confirmed by Light (I've only taken one course in meteorology, plus flight training) to be highly adequate to explain the formation and sustaining of both tornadoes and cylones. The reverse currents "over and above" the diagram are clearly explained as part of the "positive feedback loop." Condensation of the uplifted warm water and thermal conduction are sufficient evidence for me.
    In addition to the downdraft producing the spin, the initial updraft of warm moist air in the low pressure zone also produces a spin as it rises. This is what I have read quite a few times. Can you confirm this?

    URI: Again, I am not discrediting your theory, as it does have some merit, but after five hours of researching this I have found no evidence of an electromagnetic field being the cause or sustaining force of a tornado, hurricane, or cyclone. In fact, I have found no references to EM at all! Yet, this is not to say that an EM doesn't exist! Water cohesion is held together through hydrogen bonding. A cyclone would try to break this bonding apart via centrifugal force. Because of the charged in the water molecules, I would think that there should be at least a slight amount of EM present.

    However, I have read probably all of Erik Rasmussen numerous published scientific journals articles, and, although he uses mostly Dopler Radar to arrive at his conclusions from the 1994-95 "Verification of the Origins of Rotation in Tornado Experiment (VORTEX)," I find it hard to below that he would not have at least tried to use a gaussmeter to check for EM during this United States Government (NOAA) funded two-year experiment. Had he found any evidence that EM was involved in the formation, circulation, and sustaining of a tornado, then I think he would've at least made reference to it somewhere. This scientist now works for the NOAA and has spent his entire life tracking and anayzing tornadoes - initiqally with the National Severe Storms Laboratory (NSSL).

    As I said, your theory has merit, but I think that the posting of the magnetohydrodynamics diagram was premature and deceiving. There is no empirical evidence that this applies to tornadoes and cyclones at all.

    At this point, since I have virtually exhausted all the sources available online or written in books and journals, I think the only way to proceed is to directly contact either:

    1) Erik Rasmussen
    2) the National Oceanic and Atmospheric Association (NOAA)
    3) the National Severe Storms Laboratory (NSSL).
    4) the United States Air Force, Air Force Weather (AFW), with reference to their University Partnering for Operational Support (UPOS) that is now mapping EM propogation forecast maps.
    5) NASA

    NASA and the USAF would definitely know if EM or MHD is produced in tornado or hurricane formations as this would affect the vital instrumentation of their aircraft. What if the space shuttle were forced to land during a storm? They would have to know this!

    Again, after five hours of researching, I have found no indication or references to EM or MHD in tornadoes and cyclones. We can not proceed without some sort of further evidence. The theory described in Wikipedia and confirmed and ellaborated on very clearly and concisely by Light, do not leave me with any further questions: the evidence and explanations are adequate to me.
     
  14. Light Registered Senior Member

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    Yes, Valich, that is correct. It was my fault for failing to mention it. But at that moment I was primarily concerned with explaining how the downdraft - which plays the predominate role in this - was responsible for causing the horizontally rolling mass of air (a rolling "log", if you will) to be forced into a more vertical position.

    In all fairness, I must mention that EM activity is well-known to be present in tornadoes. But in no way linked to URI's rather, umm, "revolutionary vision."

    Long before the development of weather radar and Doppler in specific and warning systems (during the 1950s and 1960s) people were told how to detect a tornado with an ordinary TV set. This was also prior to the days of cable TV so it involved using your home antenna. The procedure was very simple. Switch to an unassigned channel in your area and observe the "snow" (interference). There will always be a certain level of background noise present but when a tornado is within range - 10 to 15 miles, depending on it's intensity and size - you will see a very noticeable increase in the brightness of the snow. And it will actually pulse slowly. Lightning can be detected at the same time but is discernible as single, momentary bright pulses while that made by the tornado can fairly accurately be described as similar to "slow breathing" in rhythm.

    It may very well be that URI is aware of this and it might even form the basis for his theory. But what he is failing to tell, or possibly doesn't even know, is that the field generated is extremely weak. And that's precisely why the high-gain of a TV's receiver (which automatically cranks wide-open with a no-signal condition like this) cannot detect the storm until it is almost on top of you.

    This field in generated just as you described and in precisely the same manner as lightning is created - the rapidly moving air strips electrons from the water molecules which also leaves ions behind as well. But it is a continuous process - as compared to individual thunderbolts - and that's why it's detectable in the UHF frequency band as a present but varying signal - compared to just a spike.

    As I said a moment ago, URI may have used this as a basis for his theory. But his problem is that he is taking it to absurd levels in attempting to create and describe a phenomenon that simply doesn't exist. There just isn't sufficient energy present (and he is incapable of presenting data to support it - it's just not there).
     
  15. URI IMU Registered Senior Member

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    >> the field generated is extremely weak.

    and so is "gravity"

    you, Light, have very bad tunnel vision.

    Yes, you won't find my theory anywhere else except from me.

    And that makes it incorrect ?

    as i said
    How does 'your' understanding explain the coherence ?

    I have shown for an example hurricane
    "gravity' is manifest, and i gave you a value.

    I really have no time for people who know nothing, and yet criticise... its easy to do, but it gains nothing.
     
  16. valich Registered Senior Member

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    Do you have a source on this?

    URI: Again, We can not proceed without some sort of further evidence. The theory described in Wikipedia and ellaborated very clearly by Light, do not leave any further questions: the evidence and explanations are adequate. The only way we can proceed is by contacting the organizations that I have listed above. It would be very easy to email them and post the replies.
     
  17. valich Registered Senior Member

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    Light: I mean do you have a source on EM related to tornado or cyclone formation and sustenance.

    As a side note: interesting experience. A couple hours ago I was litening to NPR on the radio. Suddenly an extremely low-flying helicopter passed overhead and I lost all reception. Sort've just like the t.v. interference you describe?
     
  18. Light Registered Senior Member

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    I'm very sorry to say that I don't. That was a very long time ago and there are much better ways of detection today that provide considerably (most of the time) warning times.

    Perhaps another of our older members, like Baron Max, Cottontop or others will remember when that advice as passed out.

    I can also tell you (again with no substantiation, I'm afraid) that my family used the method several times. And there were a few occasions when we DID see something on the screen and on two of those occasions there were actually touchdowns not too far away. Also, I had a single occasion to see a tornado at night in a completely open area (no power lines) and I clearly saw a slow, pulsing, dim blue glow that lasted for nearly four seconds. It certainly looked just like other electrical corona discharges that I've seen.

    I'm terribly sorry to have to present all this in just a "first-person experience" format because I have difficulty accepting things like that myself.

    I really hope someone else remembers and can come to my rescue!
     
  19. Facial Valued Senior Member

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    After reading this thread over, sadly, yes.
     
  20. valich Registered Senior Member

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    Why "sadly"??? There's absolutely no evidence to date! I've listed five organizations that anyone could easily email to to find out further evidence on this subject. Why should I have to do this after already using five hours exhausting all other sources? You could email any one of these organizations just as easily as you can post a post on these forums. Do it!
     
  21. Light Registered Senior Member

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    I haven't fired off any emails yet but here's the results of a very quick Google search and some links that discuss it.

    http://www.straightdope.com/classics/a1_166b.html

    http://umbc7.umbc.edu/~lharris/tornadoes.htm

    It was called the "Weller Method" (I didn't even remember that name before) but here's a link that says it can work in theory but should NOT be relied upon and it's from NOAA:

    http://www.srh.noaa.gov/fwd/media/severe/weather.htm

    All of that being said, these links at least establish what I said about EM activity being present.
     
  22. valich Registered Senior Member

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    URI: I'll try to find some email addresses tonight. If so, then I'll write something on the order of "We are doing extensive research on the formation and sustaining activities of tornados and cyclones and would like to know if you have found any indication that an electromagnetic field or magnetohydrodynamics are involved in it in anyway. Thank you." How does that sound to you? I will first do a bit more research on the subject and look over the websites you have provided.

    I personally do not think that EM or MHD are involved in the formation because the initial spin is clearly caused by the Coriolis effect. This is obvious and well documented. Heat condensation and the conservation of angular momentum are the sustaining forces. Also defined are five major conditions necessary for formation:

    1) warm water and warm moist air
    2) a decrease in temperature with height
    3) a pre-existing weather disturbance with vertical wind shear
    4) a center low pressure area
    5) a Coriolis effect: the strength of which varies depending on its distance from the equator and tends to move cyclones to the poles (tornados and cyclones cannot form at the equator because the Coriolis effect is too weak there)
     
  23. Facial Valued Senior Member

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    Errr, happily?

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    I find it hard to believe that direct EM forces (other than natural atomic collisions in fluids) can play a major role in the driving force behind cyclonic disturbances.
     
    Last edited: Nov 28, 2005

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