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RF-Seismograph: White Island Eruption causes worldwide Radio Blackout

Discussion in 'Amateur Radio News' started by VE7DXW, Dec 9, 2019.

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  1. W1PJE

    W1PJE Ham Member QRZ Page

    Tying this back to the science literature and being a bit more specific, there are multiple papers showing how fast the D region electron density recovers from an extreme forcing due to inputs from e.g. auroral precipitation, solar flares, and other related inputs. For example, J. K. Hargreaves published this paper in 1980 on observations using an incoherent scatter radar located in Chatanika, Alaska at the time. It directly measured ambient electron density through the Thomson scatter technique (*). The target was auroral precipitation "spike" events from 20-40 keV particle inputs, which are short duration (like an earthquake). "The measurements show exceptionally large electron densities in the D-region during spike events, the electron density typically exceeding 1E6 cm-3 at 90 km altitude for a short time. " (That's approaching 100 times the normal background D region density! Huge!)

    Hargreaves, J. K. (1980). D-region electron densities observed by incoherent-scatter radar during auroral-absorption spike events. Journal of Atmospheric and Terrestrial Physics, 42(9-10), 783-789. doi:10.1016/0021-9169(80)90081-1
    https://www.sciencedirect.com/science/article/pii/0021916980900811

    The image below shows Figure 5, one of the most intense events recorded. It plots absorption (i.e. blackout) in dB at 30 MHz - 10 meter band - due to the ionosphere as a function of time. Notice the time scale on the bottom: even with a massive amount of extra electron density added to the D region (a known increase from the separate electron density profiles measured by the radar; see the article for figures), absorption recovers to background level in < 5 minutes.
    Screen Shot 2019-12-20 at 8.39.48 AM.png
    This response time matches well the community's coupled chemistry models of production and loss in the D region (e.g. the Sodankyla Ion Chemistry Model) and such texts as Banks and Kockarts (Aeronomy; 1973), which detail D region chemistry in frightening detail.

    Solar flares or radiation belt inputs are harder radiation yet (up to relativistic; MeV+) and electron density enhancements take 30 minutes to 1 hour to recover in that case since they penetrate deeper and cause more widespread enhancement. But no matter what the cause of the enhanced electron density (and what frequency you are using to probe it), the relevant point here is the recovery time for D region electron density - the thing that creates absorption - back to normal levels. You would have to turn the knobs "all the way to 11" and way way beyond to get anything close to a 4 hour recovery - i.e. electron density increase levels not normally seen on this planet from any natural cause.

    Hopefully that background is helpful as this analysis is pursued further by the hive mind.

    (*) Thomson/incoherent scatter radar systems have a 60+ year history of measurement and have been cross-calibrated / vetted many, many times with other techniques like Langmuir probes on spacecraft, ionosondes, etc. See e.g. Evans, J. V. (1969). Theory and practice of ionosphere study by Thomson scatter radar. Proceedings of the IEEE, 57(4), 496-530.
     
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  2. VE7DXW

    VE7DXW Ham Member QRZ Page

    Hi Phil and Bonnie;


    Thank you for the information. It deepens my understanding of the whole issue. But what happens during solar minimum or during night time, when you have very little x-ray radiation that builds up the layers. During periods of strong solar x-ray activity the effect of the earthquakes gets overpowered by the radiation from the sun. Now we are at solar minimum and we still can have over the horizon communications in the lower HF bands and the lower energy of the quakes (compared to the solar radiation) takes over and tilts and disrupts the reflective layers very similar to the way sunspots do it to plasma on the sun. In a way you can say that sunspots are the equivalent of earthquakes. At the sun we accept the field lines come out of sunspots because we can see them and they are undeniable there. So why do we have such are hard time applying the same concept here on our planet. Of course the energy levels here on earth are a few magnitudes lower, but the physics work on the sun so why not here!


    This is a movie about the solar magnetic field and I believe that the earth's magnetic field is more like that of the sun. Earthquakes behave just as sunspots in their electrical and magnetic nature.




    Alex
     
  3. W0AEW

    W0AEW Ham Member QRZ Page

    lower energy of the quakes (compared to the solar radiation) takes over and tilts and disrupts the reflective layers very similar to the way sunspots do it to plasma on the sun.

    Sunspots tilt plasma on the sun = Earthquakes tilt ionosphere?
    Apples = Oranges?

    I know nothing, but I'd think the mechanisms would be radically different, if these phenomena actually occur.
     
  4. W1PJE

    W1PJE Ham Member QRZ Page

    The Earth's magnetic field is vastly different from the Sun. We have hard data on this fact - many measurements both at the ground and in orbit have characterized the terrestrial magnetic field to a precision not available for any other celestial object. For example, the SWARM mission from the European Space Agency has a primary purpose of making extremely precise magnetic field measurements - and they have done so. They are all compatible with a background field with regional anomalies (e.g. the South Atlantic Anomaly) which slowly changes over time. Anomalies beyond these levels are simply at too low a magnitude to affect the bulk ionosphere in the manner suggested above - magnitude matters, not just qualitative physics.

    Consider: a very strong auroral current signature (with vast amounts of global energy input compared to a regional earthquake) produces magnetic disturbances on the order of 100s of nanoTesla - really strong ones in the 1000s of nanoTesla. Now compare with the background magnetic field value of 25,000 - 65,000 nT. So the auroral magnetic distortion in its strongest form is .. 4% of the background magnetic field. Is the implication that an earthquake produces magnetic signatures exceeding these levels? The evidence does not seem to support that, for if it did, it implies that terrestrial compasses would be pretty useless in earthquake regions, and that has not been reported as far as I know.

    By contrast, the Sun is not a solid core body but is a quasi-chaotic magnetized fluid with embedded current flows, so the field of magnetohydrodynamics (MHD) applies. Vastly different physics from the molten core eddy and diffusion currents that drive Earth's magnetic field. So the data just do not support the Earth's field having similar behavior to the solar field.

    Regarding the potential tilting of ionospheric layers, again, the numerical physics do not support this assertion. Electrons remain strongly magnetized to deep in the ionosphere, and it takes a relatively large amount of energy to move them across magnetic field lines compared to parallel (along them). Again looking at the numbers, the level of magnetic distortion needed to tilt the ionosphere in the manner suggested is so high as to negate the idea of a background field entirely - and again, we know the relatively stable background field strength and direction from data.

    Finally, a couple other things. The ionosphere is created by solar extreme ultraviolet radiation - EUV - illuminating the neutral atmosphere, not solar X ray output. The reason why the nighttime ionosphere exists, when solar illumination is not present, is a combination of slow chemical electron recombination (hours long) in the F region combined with horizontal and vertical transport of ionization from regions where production is still going on. The dynamic physics of this interaction are fascinating and are the reason why we still study the ionosphere over a century after its postulation.

    So to continue the discussion, it needs to become quantitative. What is the amplitude of the theorized magnetic distortion implied by the analysis to date? How does it numerically compare with the energy stored in the background magnetic field (i.e. B**2 / 2 \mu_0)? How does this numerically compare with the thermal and kinetic energy of the undisturbed ionosphere? These are good aiming points for the assertions made. The extraordinary mechanisms proposed really do need extraordinary, quantitative evidence of the amplitude of the theorized disturbance, and without the numerical information, it's very hard to provide the latter. That is essentially what Bonnie is after as well, if I understand correctly.
     
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  5. VE7DXW

    VE7DXW Ham Member QRZ Page

    How do you explain this:

    See image below, look at the green trace which is 40 m. When the trace goes thick we have propagation. You can clearly see how propagation fades when the white peaks which are earthquakes greater than M4.5 pop up with some precursor of about 1 h. You can clearly see how the earthquakes disrupt the signal strength of the received signal. Not just once but three times and this is just today?


    [​IMG]
    Thank you;
    Alex
     

    Attached Files:

  6. VE7DXW

    VE7DXW Ham Member QRZ Page

    See message above... A
     
  7. VE7DXW

    VE7DXW Ham Member QRZ Page

    See message above... A
     
  8. W1PJE

    W1PJE Ham Member QRZ Page

    Hi Alex,

    Unfortunately, it's hard to explain something when it is not clear to me precisely what is being measured. So the statement "You can clearly see how the earthquakes disrupt the signal strength of the received signal." - actually, I am failing to see that clearly.

    When looking at things like this, the only way to proceed is to attempt first to address questions about the data (not any further correlation to events like earthquakes or related) that are standard ones needed for any data source:
    • What are the exact frequencies and bandwidths used by your instrument?
    • What is the passband filter shape? Is it non-flat? Is this calibrated? If so, how?
    • What exactly is being measured and plotted?
    • How are measurements calibrated, converted to stable absolute (or relative) intensity, and traced to a known calibration standard?
    • What is the uncertainty associated with each measurement?
    • What is the vertical scale on the plot and in what units?
    • How do you distinguish human-created signals in the nearby / local environment from long path DX propagation when there may be no angle of arrival determination involved in the measurement? Both will mix together if present at the antenna and could have vastly different behaviors.
    Without this sort of information, I find it impossible to interpret wiggles on a graph as being anything more than an instrumental artifact, even though it might not be that. (That's science for you.) I realize that some of it might be in a manual somewhere, but sadly, I do not have time to dig it out from there or from groups.io postings. To address the questions posed in this general thread, answers to each of these questions here would be efficient and would address questions others have expressed as well.

    BTW, I think the numerical analysis questions on the theory candidate in the last part of my (long) paragraph a couple posts above are still needed. But you must have this information already if you're producing analyses of some sort, so it should be straightforward to list that information.
     
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  9. KQ6XA

    KQ6XA Ham Member QRZ Page

    Dear VE7DXW,

    As I understand it, you are using that image as evidence that you are seeing precursors for earthquakes by receiving randomly transmitted ham radio signals.

    Honestly, it doesn't appear to be what you think it is.

    As one friendly ham to another, I would suggest that it may be in your interest to avoid doing that until after you research and understand the scientific method and the kinds of standards that are common in this field.

    Controls for your experiment, and calibration of your equipment, can help you to understand random events or possibly see actual correlation.

    Absence of evidence is not the same as evidence of absence.

    Some friendly hints.

    1. Define a question
    2. Gather information and resources (observe)
    3. Form an explanatory hypothesis
    4. Test the hypothesis by performing an experiment and collecting data in a reproducible manner
    5. Analyze the data
    6. Interpret the data and draw conclusions that serve as a starting point for new hypothesis
    7. Publish results
    8. Retest (frequently done by other scientists)

    The 4th item above is a good one to concentrate on.
    "collecting data in a reproducible manner"
    Also, the peer review of your published results were mixed reviews, so that's an area that can be worked on.

    If you intend to go down the path of oblique (sounding), you are going to need some known distant signal sources as "controls" for the experiment. Perhaps WWV and WWVH would be good for that purpose.
     
    Last edited: Dec 21, 2019
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  10. N3HGB

    N3HGB Premium Subscriber QRZ Page

    I used to be convinced I had some magical power to burn out streetlights when I was a little kid. Some of them burned out right when I walked under them.
    My mother pointed out that maybe they burned out all the time and I didn't know about it because I was only looking at the ones I walked past.
     
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  11. KK4NSF

    KK4NSF Ham Member QRZ Page

    SO!!!! Maybe you are the cause of all the QRM around here! :mad: We need to buy you a Faraday Suit.... then the world would be quiet once again. :D
     
  12. ZL2SCI

    ZL2SCI Ham Member QRZ Page

    Ok slightly off subject currently there's hydro geo magnetic survey being carried out of regional Aquifers associated with rivers in the region using a Large coil suspended from a helicopter at various heights above the ground to generate a reflected signal from within the aquifers concerned .... much in the same way as mineral bodies are scanned for in geo stratas , ie gold silver and other minerals .... Respect to the aquifer data this is a relatively new .
    Now back to Earth Quakes generating Interference or energy spikes ,,, It was reported that a Geologist observed a coronal type effect in the atmosphere above a fault fracture Zone which both up lifted about 9m at one end and the fault surface moved over a distance of 150 kms approx
    So my comment is knowing the tremendous forces involved ie squeeze the rock at failure points I wonder just much energy is created to give the effects ... Whether one could also show similar effects of sprites above thunder storms as observed from the ISS either way re earth quakes and thunder storms tremendous amounts energy discharged in each case ...
     
  13. VK5OHR

    VK5OHR Ham Member QRZ Page

    What a great find here on QRZ!

    Earthquakes and Radio propagation

    https://groups.io/g/MDSRadio

    [​IMG]
     

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