[HN Gopher] Low-frequency sound can reveal that a tornado is on ...
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Low-frequency sound can reveal that a tornado is on its way
Author : billybuckwheat
Score : 39 points
Date : 2023-12-13 18:49 UTC (4 hours ago)
(HTM) web link (www.bbc.com)
(TXT) w3m dump (www.bbc.com)
| h2odragon wrote:
| (1976) https://www.straightdope.com/21341329/how-to-detect-
| tornados...
|
| Modern TVs, not so much. A quick glance doesn't show anyone
| working to make an RTLSDR tornado detector, which prolly means I
| just missed it. Seems like it shouldn't be too hard.
| westurner wrote:
| Looks like there are RPi infrasound monitors specifically for
| geologic seismology;
|
| "Raspberry Shake", "RS&BOOM"
| https://manual.raspberryshake.org/boom.html#technical-specif...
| https://shop.raspberryshake.org/infrasound/
|
| FWIU infrasound may indicate Earthquake, Fire, Tornado; and
| probably IDK Stampede?
|
| Infrasound: https://en.wikipedia.org/wiki/Infrasound
|
| FWIU the _Phononic_ wave signal is embedded in the _Photonic_
| wave signal, and so it may be possible to create even less
| extensive infrasound sensors;
|
| "Quantum light sees quantum sound: phonon/photon correlations"
| (2023) https://news.ycombinator.com/item?id=37793791
| dylan604 wrote:
| "They rarely have much warning, but it is often enough to save
| lives."
|
| I really wish this trope would go away. If you live in an area
| prone to tornadoes and you "have no warning", then you're just
| not paying attention. We know tornadoes exist. We know where they
| tend to frequently occur. The local weather stations in those
| areas are pretty damn good with warnings. We know days ahead of
| time that the conditions will be right for potential activity. We
| can now see potential tornadoes before they are formed. We can
| track their paths with neighborhood cross street precision.
|
| Nevermind the fact that there's a pretty good indicator when the
| sky turns dark and the weather changes. Thunder and lightning and
| wind are essentially the knocking on the door. It's not like it's
| a sunny day and a tornado just pops out of the sky to say hello.
|
| To say no warning just means they are not paying attention. I
| don't know what the tornado activity is like where the BBC is
| from, but it is woefully out of date.
| Kon-Peki wrote:
| > I don't know what the tornado activity is like where the BBC
| is from
|
| London. The British Broadcasting Corporation is from London, in
| the UK. And they do have tornados in the UK.
| philk10 wrote:
| the article references a team from Oklahoma State University
| marcellus23 wrote:
| He was not literally asking where the BBC is from.
| pixl97 wrote:
| Eh, as a person that's lived in tornado alley and done a bit of
| chasing myself this doesn't really cover all the bases.
|
| Yes, there are high risk days seen pretty far out, and these
| get all the chasers hot and bothers.
|
| There are also other days with almost no chance of severe
| weather when you get a spin up tornado that may only last 10-15
| minutes but does a surprising amount of destruction with no
| warning.
|
| Add to this that in the midwest/tornado alley you have a lot of
| other storm days without tornadoes. Out of any given day, one
| out of 8 will be one with rain, actual tornado days (within 100
| miles) are far lower.
| dylan604 wrote:
| does anything you just retorted with qualify as "rarely
| having" warning?
| h2odragon wrote:
| https://www.weather.gov/meg/GibsonWeakleyTornadoSurveyResult...
|
| This twister happened the other day, probably about 20 miles
| from me. I was aware of the warning and watching the radar; but
| aside from that I would've had no clue it happened.
|
| We saw the house lights flicker a little bit; there were some
| clouds to the northwest that looked dark, but not especially
| menacing, and that was it. Some of the people in the path of
| that tornado had exactly the same experience, until it was
| moments away.
|
| This one, in 2021; killed people who were at work. As I recall
| they warnings had been on and off all day for much of West TN
| and KY.
|
| https://www.courier-journal.com/story/news/local/2021/12/11/...
| dylan604 wrote:
| "I sent you a weather forecast, a boat, and a helicopter?
| What more do you want?"
|
| I'm sorry that people just choose to ignore the weather, but
| that cannot be the fault of those literally shouting at them
| to take shelter (some of the weather people can be a bit
| enthusiastic). The TFA mentions warning fatigue, but that's a
| weak excuse. Sure, I like to make fun of the forecast as much
| as the next person, but when the storms do come, the local
| weather springs to life and all of the tech comes to the
| forefront. People choose to ignore the warnings at their own
| peril, but then feel like it's perfectly fine to then say
| "but we had no warnings".
| otteromkram wrote:
| 20 miles is pretty far away. What were you expecting?
|
| The factory one is clearly due to negligence.
|
| But, the parent comment alluded to something about "living in
| an area prone to tornadoes," which would include areas you
| described.
|
| So, any storm during tornado season would be enough to take
| precautions or at least be on alert. No?
| tkahnoski wrote:
| Watches are common, indicators are common, warnings tend to be
| very last minute.
|
| I consider myself a very weather aware person living near the
| edge of tornado alley in Dallas, I get all the alerts,
| generally keep a strong watch on radar development and storm
| arrival times (hail is just as much as a concern as tornadoes).
|
| In general if there is a detection of a rotation or a strong
| hail core on radar, emergency sirens will go on near the
| affected area. Sometimes it just happens too fast, so if there
| is another method like the article sounds to detect a strong
| potential a tornado is forming it will absolutely reduce
| casualties.
|
| As an example I lived through in October 2019. There was one
| hour between a Tornado Watch being issued and when the EF2/EF3
| hit the ground. Watches generally last a long time and cover a
| large area so they aren't particularly helpful to me other than
| to indicate to 'check the radar on the regular'.
|
| Because I was already glued to my phone I saw the warning right
| away, I was able to text friends that lived a few minutes from
| the tornado touchdown point that there was a tornado right next
| to them. Their sirens hadn't gone off yet, by the time they had
| taken shelter they heard the sirens and the wind kicking up
| right after. They got off light on damage compared to the rest
| of their neighborhood but I can't imagine someone out walking
| their dog or running an errand and then only having 1 or 2
| minutes to find shelter. I'm still amazed this thing didn't
| cause more injuries particularly in the early minutes when the
| news crews and meteorologist were playing catch up.
| https://en.wikipedia.org/wiki/Tornado_outbreak_of_October_20...
|
| Maybe this tech would have helped give a clearer indicator
| versus the usual approach of waiting to see something on radar
| or manually spotting it. Or maybe some storms will just form
| too fast to have any useful indicators.
| Tempest1981 wrote:
| Here's an example of VLF microphones, although I can't find
| pricing: (kinda want to buy one now to play with)
|
| https://www.grasacoustics.com/products/special-microphone/in...
|
| Excerpt: "To achieve a very low low-frequency cut-off of down to
| 0.09 Hz, a special microphone combined with a special
| preamplifier and a low-frequency adapter is used. To account for
| pressure variations close to 0 Hz, a special ambient pressure
| equalization system with a very long settling time is used."
| abzgupta wrote:
| weren't there some bird migration patterns which also signaled
| future weather calamities?
| remyp wrote:
| As a lifelong midwesterner I don't need sirens, the internet, TV,
| radio, or low frequency sound to warn me about a tornado. If it's
| "green" outside I'm heading down to the basement.
| teeray wrote:
| Where it's probably more useful is for places like the
| northeast, where we typically will have a tornado warning or
| two a year. They aren't the storms of myth and legend you find
| in the midwest, but they do cause damage and can kill people.
| For a population who aren't as attuned to the signs of tornado
| formation, external signals from experts can be useful.
| zoklet-enjoyer wrote:
| I agree. Tornado weather is very apparent. But it is really
| cool that there's a new method to detect them.
| myself248 wrote:
| tl;dr: 10-15 Hz.
|
| In case you were looking for a number.
|
| I wonder if existing weather stations might be able to pull this
| from their existing barometric sensors, with nothing more than
| software.
| swells34 wrote:
| It probably depends on the weather station. The cycle time on
| those pressure sensors can be ridiculously high and still give
| decent results; you really only need one measurement per
| minute. But that should be just one firmware patch away from
| being a solved problem.
| aj7 wrote:
| https://amt.copernicus.org/articles/15/2923/2022/amt-15-2923...
| jschveibinz wrote:
| This link to what DoD uses: https://defense-
| update.com/20060107_feature-ugs.html
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