Tornadoes make the earth move

From Indiana University

Scientists detect seismic signals from tornado

Earthscope

Image courtesy of Earthscope, a National Science Foundation programEarthScope Program scientists are deploying thousands of seismic, GPS, and other geophysical instruments to study the structure and evolution of the North American continent and the processes that cause earthquakes and volcanic eruptions. Shown is the complete grid of sensors that, used in concert, will give scientists the clearest picture yet of American geological phenomena. - click to enlarge

BLOOMINGTON, Ind. — An Indiana University geophysical experiment detected unusual seismic signals associated with tornadoes that struck regions across the Midwest last week — information that may have value for meteorologists studying the atmospheric activity that precedes tornado disasters.

The experiment by IU researchers involves deployment of more than 100 state-of-the-art digital seismographs in a broad swath of the U.S. midcontinent. One of the twisters that struck southeastern Missouri and southern Illinois on Feb. 29 passed through the seismic detection array.

“In examining the seismograms, we recorded unusual seismic signals on three of our stations in southern Illinois,” said Michael Hamburger, professor in the department of geological sciences at IU Bloomington and one of the researchers conducting the experiment.

“The seismograms show a strong, low-frequency pulse beginning around 4:45 a.m. on Feb. 29. Our preliminary interpretation, based on other seismic records of tornadoes, suggests that we were recording not the tornado itself, but a large atmospheric pressure transient related to the large thunderstorms that spawned the tornadoes.”

The seismographs that detected the pulse are near Harrisburg, Ill., a town of 9,000 where a pre-dawn twister caused extensive damage, killed six people and injured about 100 more.

IU researchers initially feared that some of the instruments might be damaged by the storm, setting back a National Science Foundation-funded project that included the investment of hundreds of thousands of dollars and months of effort. But when principal investigator Gary Pavlis, an IU professor of geological sciences, checked the digital recordings of the Illinois stations on Feb. 29, he found they were still alive and streaming data. As he checked further, he discovered the strange “tornado seismograms” that were recorded on seismographs near Harrisburg.

Hamburger said a seismic pressure gradient associated with the tornado produced a slow, minute tilting of the seismograph that lasted for several minutes. He said this sort of pressure-related signal may help scientists better understand atmospheric activity that takes place right before tornadoes touch down. The IU researchers are working with colleagues at the University of California San Diego to try to compare recordings with other tornado-related signals and to dig deeper into the analysis.

While seismographs have been known to detect seismic activity related to tornadoes, it is highly unusual to have state-of-the-art digital instruments recording information in such close proximity to a tornado, the researchers say.

The IU seismic experiment, dubbed “OIINK” for its geographic coverage in parts of the Ozarks, Illinois, Indiana and Kentucky, includes the positioning of 120 seismometers to study earthquakes and geological structure in a key area of North America. Installation of the instruments began last summer. They are recording thousands of earthquakes from the study area and around the world, as well as nearby mining and quarry explosions.

The $1.3 million, four-year undertaking is part of the NSF’s EarthScope program, which seeks to cover the entire U.S. with a grid of detection devices for the purpose of better understanding seismic activity and predicting earthquakes. Researchers liken EarthScope to “an upside-down telescope” that allows them to look into the Earth and gain a better understanding of seismic forces.

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More details on the experiment are available at newsinfo.iu.edu/news/page/normal/18612.html.

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49 Responses to Tornadoes make the earth move

  1. RobW says:

    Interesting but what is the lead time between signal and tornado?

  2. cromagnum says:

    Sounds like something I might have read from the dutch media, but it does make sense when explained this inverted way.

    Which came first?:
    a) strong, low-frequency pulse
    or
    b) a large atmospheric pressure transient

    Did they track the pre – tornado activity at high resolution weather maps? Unfiltered radar shows the early precipitates formations clearly.
    And with any science, can that same phenomenon be found in the multiple other Tornado outbreaks around the US?

  3. RockyRoad says:

    The atmosphere exerts a force of about 14 pounds per square inch over the entire earth’s surface, which comes to over a ton of pressure per sq ft, or 28 million tons per square mile. The fluctuation of just a very small part of that pressure would understandably show up as a seismic signal.

  4. Lew 'Big Oil' Skannen says:

    That’s it! That is what the loons have wanted to hear all along!

    Co2 => change in atmosphere => more wind => seismic effects => Wild killer tornadoes which home in on old people, poor people and cute furry animals.

    I hope you are proud of yourselves etc …

  5. TG McCoy (Douglas DC) says:

    This is not surpising . Having been spit out of the top and bottom of big thunderstorms,
    and had nearly been slammed into the earth by a downburst- in a 108,000 lb DC7,
    Maybe there can be predictive study done here…

  6. DirkH says:

    “An Indiana University geophysical experiment detected unusual seismic signals associated with tornadoes that struck regions across the Midwest last week — information that may have value for meteorologists studying the atmospheric activity that precedes tornado disasters.”

    So they have recorded signals while the tornadoes struck? Wouldn’t it be an easier way to observe tornadoes by simply watching them? Their detection doesn’t have predictive skill.

  7. ntesdorf says:

    Look Hansen, real scientific work being done here. What a change!

  8. JinOH says:

    Whateva. Mother nature is a b!tch.

    I just want it to stop raining in Ohio.

  9. Steve says:

    Sure these instruments are not just ‘feeling’ the thunderstorm?
    sheesh, as usual, more testing needed, please send money!
    /sarc

  10. Jeff D says:

    DirkH says:
    March 8, 2012 at 9:10 pm

    __________________
    I think you may have missed this part. ” He said this sort of pressure-related signal may help scientists better understand atmospheric activity that takes place right before tornadoes touch down.”

    They are talking about the predictive value of the readings. ie the pressure drop in a geographical area just before the formation of a funnel can be sensed as a seismic signal.

    Being located in tornado alley this is a pretty interesting piece for me.

  11. DirkH says:

    …and IF they recorded a signal BEFORE the formation of actual tornadoes, the next obvious question would be, what’s the false positive rate, and can they say exactly where the tornado will hit. Because otherwise you just end up alarming the whole country for naught, and the warnings would immediately be ignored by everyone…

  12. DirkH says:
    March 8, 2012 at 9:10 pm

    “An Indiana University geophysical experiment detected unusual seismic signals associated with tornadoes that struck regions across the Midwest last week — information that may have value for meteorologists studying the atmospheric activity that precedes tornado disasters.”

    So they have recorded signals while the tornadoes struck? Wouldn’t it be an easier way to observe tornadoes by simply watching them? Their detection doesn’t have predictive skill.

    Not all tornadoes can be seen, many happen at night, and many are obscured by clouds, rain, hail, and dust etc. The inflow winds can substantially reduce local visibility even if the view path is clear. In much of the country local terrain, trees and buildings mask them from view until they are very close.

    That is why radar is the primary method of monitoring tornado development over wide areas. Even a skillful trained spotter has great difficulty getting close to a tornado during critical stages of its development. That is why even though active research on tornado development has been going on since the 1950′s it was not until recently that anyone had succeeded in getting actual measurements of central pressure of a tornado and that was only a brief sample of a single event.

    Observing tornadoes is much easier imagined than done.

    It will be interesting to see how the seismic signal corresponds with other possible tornado indicators like infra-sound, and electrical signatures (electrical noise sometimes seen on television sets) that some have reported. If reliable this might be an excellent way to provide a second independent signature to validate suspected hook echo signatures of tornadoes on radar.

    Larry

  13. u.k.(us) says:

    TG McCoy (Douglas DC) says:
    March 8, 2012 at 9:04 pm
    This is not surpising . Having been spit out of the top and bottom of big thunderstorms,
    and had nearly been slammed into the earth by a downburst- in a 108,000 lb DC7,
    Maybe there can be predictive study done here…
    ================================
    Ummm, passenger or cargo flight ?, no radar ?, flight logs, no pilot would say “nearly slammed into the earth” without providing details of his recovery from his flight into a thunderstorm.

    Please stop with your stories, they fool nobody.

  14. Brian Johnson uk says:

    As scientific instruments become more sensitive, through modern technology, it only needs the media to spread the hyped hysteria and modern mankind [the Green part] screams “Save our Planet!” or similar.

    I blame ’24 hour Breaking News’ and the 100% safety/compensation mindset.

  15. Rob Dawg says:

    The best part is that it raises more questions than it answers. More funding!

  16. wayne Job says:

    These instruments are a tad sensitive and a local backwoods farmer removing the odd tree stump or three with dynamite may cause a state wide panic.

  17. the fritz says:

    I agree; I am sure that for Venus it is the strong wind and heavy atmosphère that make this planet move

  18. AndyG55 says:

    Going off like a tornado.. and making the earth move… hmmmm !!!

  19. Alan the Brit says:

    Jeff D says:
    March 8, 2012 at 9:38 pm
    DirkH says:
    March 8, 2012 at 9:10 pm
    __________________
    I think you may have missed this part. ” He said this sort of pressure-related signal may help scientists better understand atmospheric activity that takes place right before tornadoes touch down.”
    They are talking about the predictive value of the readings. ie the pressure drop in a geographical area just before the formation of a funnel can be sensed as a seismic signal.
    Being located in tornado alley this is a pretty interesting piece for me.

    Jeff, (if I am reading you correctly) is there enough lead in time with these things, as somebody suggested earlier? With all these things, it’s the amount of time the warning gives you that is crucial. Piers Corbyn seems to do rather well at predicting these events with some measure of skill, but even he can only regionalise on a large scale, not so easily on a local scale.

    For me, if the “enemy” (no names) drops the bomb on the UK, we get at best four minutes warning (assuming rocket motors are still technically back in the 70s – unlikely unless an aging fleet), to do what precisely I am not entirely sure, pray to ones maker I suppose, damn all else one can do.

    Equally, having advanced warning of an earthquake & its location, would only serve a purpose if it was say a couple of hours perhaps to evacuate the local population if possible in such a timeframe, otherwise it’s nothing more than a hellish torment to those who await impending disaster rather helplessly.

  20. Steve C says:

    Brian Johnson uk says: (10:43 pm)
    As scientific instruments become more sensitive, through modern technology, it only needs the media to spread the hyped hysteria and modern mankind [the Green part] screams “Save our Planet!” or similar.

    The truth of that is to be found in no less an organ than the Daily Telegraph, in Geoffrey Lean’s blog. He observes that “Americans are starting to believe in climate change – but for the wrong reasons”:

    Yet the main reason for the shift – which is also seen in other recent US polls – appears to have been recent weather patterns, which, whatever some sceptics and greens claim, is a different matter from longer term climate change. Two years ago, polls showed (as in Britain) that the harsh winter had been the main factor in persuading people that global warming was not taking place. Now, warmer temperatures and an increase in droughts, storms and other extreme events – four out of five Americans live in states hit by weather-related disasters since 2006 – are (equally wrongly) fuelling a growing conviction that climate change is happening after all.

    Brian’s right, unfortunately. In the red corner, boring old scientific facts. In the blue corner, media celebrities and talking heads freely extemporise on the theme of manmade apocalypse. Which will catch the attention of a largely scientifically illiterate generation raised on multimedia? Come to that, what would Geoffrey Lean regard as “the right reasons” for believing in a falsehood, I wonder?

  21. pat says:

    naturally Seth was the AP solar storm scare go-to man, and is still smug:

    8 March: AP: Seth Borenstein: Solar storm not nearly as bad as could have been
    By SETH BORENSTEIN, AP Science Writer – 1 hour ago
    AP Business Writers Josh Freed and David Koenig contributed to this report
    “We’ve seen a bit of an increase in mag (magnetic field) geo-activity, relative to what we saw earlier today,” said Norm Cohen, a senior space weather forecaster at the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center in Boulder, Colo…
    Hours earlier, NASA solar physicist David Hathaway said that it appeared that the storm was over, based on a drop in a key magnetic reading…
    It was never seen as a threat to people, just technology, and teased skywatchers with the prospect of colorful Northern Lights dipping further south.
    But when the storm finally arrived around 6 a.m. EST Thursday, after traveling at 2.7 million mph, it was more a magnetic breeze than a gale…
    http://www.google.com/hostednews/ap/article/ALeqM5gjNDef54eydBsxSmIlaGlojH4_Ow?docId=66dacc0267c442d786dd8fc0b0a873d1

  22. Dr. John M. Ware says:

    I found the article quite interesting. I grew up in Indiana and attended IU. I still remember very well the night of Palm Sunday 1965, when a huge tornado outbreak did heavy damage across several states, including a town about 20 miles from where I was playing a church service. I have never stayed outside while a large tornado went overhead; I came close enough a year and a half ago here in Virginia when a tiny tornado (force 0, maybe 50 yards wide) came through our yard straight for the house at amazing speed. Watching from a front window, I couldn’t see a funnel cloud as such, just a whirling of debris that–yes–roared like a train, rattled against the house, and sped on. Tiny as it was, and low as were the wind speeds recorded for it, that tornado took out our largest and oldest tree, numerous very large branches from other trees, and our two largest bushes, including a rose 18 feet high and 32 feet across. Our neighbors across the street lost 8 large trees. The tornado was invisible until it hit, though I could hear the wind for a few seconds ahead of it.

    It is possible that the scientists at IU are working from a prejudice toward CAGW; but even if so, it is also possible for new and useful things to be found out. Those pressure differences over large areas of land could very well provide data about changes under the ground surface, and I’d like to see what comes of the research.

  23. cb says:

    I agree with ‘detection is not prediction’ above. Moreover, I would state (the obvious) that more measurement is not really more information either. (Beyond the trivial, that is.)

    Sure, lots of what is seen as noise (in some types of measurement) is, in fact, made up of various random events doing their thing. But frankly, so what? Modern devices allow for ever more accurate measurement… … of what is, in the absence of sufficient cause-effect chains, still NOISE.

    And if anyone thinks that statistics will ride to the rescue, given its complete divorce from the very concept of cause-effect, then they are deeply delusional. Had something similar yesterday in a meeting: a kind of madness that says that being able to measure more is somehow, magically, going to provide more INFORMATION. Of course, pointing this out was met with actual derision. Oh well, how was I to know that about the magic information bit that is attached to every signal, which clearly indicates its providence? And, of course, that every signal is a good hippie, and will stand clearly and uniquely differentiated from all the other hippies in its clan? Now, of course, I know better: I feel so deeply privileged to have been offered their correction (blinks tears from eyes).

  24. Mike McMillan says:

    wayne Job says: March 9, 2012 at 12:15 am
    These instruments are a tad sensitive and a local backwoods farmer removing the odd tree stump or three with dynamite may cause a state wide panic.

    I got to do some stumps with my dad as a boy, and there’s no way a seismograph will confuse that bang with a tornado. Light the fuse and run – does it get any better than that for a kid?

    Pop kept a case of dynamite in the garage, but I think he threw it out when it started to sweat nitro.

  25. polistra says:

    I’d say the Severe Storms Center already understands the “atmospheric activities” that take place before a tornado. They’ve been predicting with a half-hour lead time for MANY years. Nearly always enough time to reach shelter.

    The real problem is poor response by broadcasters and other local communication in states outside Tornado Alley. (i.e. states that haven’t learned from Gary England.)

  26. Johnnythelowery says:

    I think their numbers are skewed. There is a direct effect of the frequency and locality of Tornadoes by the……………….

    Trailer Park Island Effect

  27. Kiersten Marek says:

    Reblogged this on Kmareka.com and commented:
    Interesting news about scientists discovering a connection between tornadoes and seismic activity.

  28. 1DandyTroll says:

    Maybe they need to retune their equipments since the 10WALB posted news from heartland news at 4:35 PM CET about possible tornado that swept through the area killing 10 in souterhn Illinois and south east Missouri.

    So it seems they picked up the signal a little too late.

  29. Doug W says:

    I think some WUWT readers may be suffering from PAGWS (Post-AGW Syndrome)! Years of disputing silly, over-the-top claims by warmists have left us overly skeptical of science news in general.

    I think this is an intriguing piece of information, the sort of accidental discovery that may lead to something useful. It may also lead to nothing at all, which is the nature of research.

    Now if it turns out that the warmists link all this back to CO2 (the miracle gas that can do anything at all) I will retract my statement about being overly skeptical.

  30. Eustace Cranch says:

    Hey! Here’s the beef!

  31. Eustace Cranch says:

    (Hamburger, that is….)

  32. Carrick Talmadge says:

    Eartthscope has more like 400 sensors in it (“more than 100″ is an understatement). Interestingly enough for the open-source people among us, anybody here can get access to and down load any of the relevant data—it’s all publicly available.

    The component that they are probably using is called USARRAY and (slight /brag) contains infraosund sensors developed by me and manufactured under my control. That data is publicly available too.

    The data are all transmitted back from the various array components using broad-band wireless (e.e., 3G) if anybody is interested in that.

    I’d guess what they are seeing is the infrasound wave generated by the storm, and low frequency sound couples to the ground via coupling of the ground to the atmosphere. Seismic-only is less likely because generally you’re going to excite the surface wave with a storm like this, and they typically fall off pretty rapidly with distance (usually in the noise floor after about 5-km).

    That might be useful for near-field warming. I had a poster on measuring the infrasound signal from tornadic storms in the fall 2011 AGU meeting.

  33. beng says:

    Sorry if I’m hijacking this thread, but we’ve discussed the issue of the end-of-the-glacial period North American “extinction” several times on WUWT. Below is an interesting post at Universe today about a Mexican impact site:

    http://www.universetoday.com/94001/mexican-lake-bears-witness-to-ancient-impact/

  34. Jeff D says:

    Alan the Brit says:
    March 9, 2012 at 1:52 am

    Jeff, (if I am reading you correctly) is there enough lead in time with these things, as somebody suggested earlier? With all these things, it’s the amount of time the warning gives you that is crucial
    ________________________
    With large super cells warning times are decent and yes Gary England is my goto guy when the sky’s get dark. The tornado chasing craze has helped and hurt all at the same time. For the last few years it seems there are chase teams on almost every cloud that crosses the state. Little tornadoes some not much bigger than a dust devil are now being spotted and recorded on video. I have heard of grumbling from the research community that the amateurs/tour groups are getting in the way of them being able to get their equipment in place and in time to make measurements. The small storms can still pop one out with almost no notice.

    The warning times do help but when you hear the words you must be underground to survive offers no comfort when there is no ground to go to.

  35. Rob Crawford says:

    “Being located in tornado alley this is a pretty interesting piece for me.”

    My concern is whether they’ll be able to distinguish between tornadoes and New Madrid getting ready to cut loose.

    (New Madrid, MO — town motto, “It’s Our Fault!”)

  36. Mark C says:

    According to the press release (often a scary source to use for reliable info), the transient was recorded beginning at 4:45am. From the NWS storm survey, the tornado began at 4:51am and struck Harrisburg at 4:56am. That’s not a lot of lead time but at least it seems to be positive.

    I think this is more of a curiosity item rather than anything that will have predictive skill. There may be many other transients not associated with tornadoes. The storm in question might have to pass quite close to a seismometer to pick it up too.

  37. TG McCoy (Douglas DC) says:

    u.k.(us) says:
    March 8, 2012 at 10:33 pm
    28 years in Aviation- Insturment Instructor, Flight Instructor Commercial Pilot, Multi and Single Engine Land. NOAA certified Weather Observer- had to take same test as the NOAA folks,
    back in the 70′s . 11,500 hours, l worked for 91/2 years as an Airtanker Pliot. about 2800
    hours in 4-Engine Douglas aircraft. Flew as a Co-pilot. Flew air freight and Commuter airliners.
    worked as a Govn’t contract Pilot for Everone from the Department of Defence to the
    Department of Energy. 7 years running a Charter service/Flight school.
    My comment was concerning aviation safety and the idea of prediction.
    form my own perspective as a particpant.

  38. DonS says:

    Jeez. What a bunch of soreheads

  39. Scott Covert says:

    wayne Job says:
    March 9, 2012 at 12:15 am
    These instruments are a tad sensitive and a local backwoods farmer removing the odd tree stump or three with dynamite may cause a state wide panic.

    Not to mention the odd mid western “amateur pyrotech” testing out this months batch of black powder.
    I wonder if DHS helped fund the project?

  40. Dirk says:

    ” EarthScope Program scientists are deploying thousands of seismic, GPS, and other geophysical instruments” to study the structure and evolution of the North American continent and the processes that cause earthquakes and volcanic eruptions”…..
    Maybe Earthscope should first figure out that “North America” doesn`t end North of the 49th Paralell…

  41. TonyG says:

    DirkH says:
    …and IF they recorded a signal BEFORE the formation of actual tornadoes, the next obvious question would be, what’s the false positive rate, and can they say exactly where the tornado will hit. Because otherwise you just end up alarming the whole country for naught, and the warnings would immediately be ignored by everyone…

    So, what are you suggesting? It sounds a lot like you’re just dismissing this completely. Should they have not bothered reporting the observation, because they can’t immediately make use of the information?

    Seems like you’re demanding quite a bit from a single observation of a phenomenon.

  42. Scott Covert says:

    TonyG says:
    March 9, 2012 at 11:50 am
    DirkH says:
    …and IF they recorded a signal BEFORE the formation of actual tornadoes, the next obvious question would be, what’s the false positive rate, and can they say exactly where the tornado will hit. Because otherwise you just end up alarming the whole country for naught, and the warnings would immediately be ignored by everyone…

    So, what are you suggesting? It sounds a lot like you’re just dismissing this completely. Should they have not bothered reporting the observation, because they can’t immediately make use of the information?

    Seems like you’re demanding quite a bit from a single observation of a phenomenon.

    By the way they described the signal, it sounds like it is a long DC offset which is pretty much the opposite of an impact like explosives or periodic vibration from volcanic/ tectonic action. There are probably other phenomenon that cause offsets that could cause false readings.
    What this study will more likely do, is help scientists in the field design new sensors that can more accurately measure this effect.

  43. Laurie says:

    To my knowledge, it’s not typical that these stations are monitored real time other than to check that they are operational. Most of the data is recorded and stored for researchers. I suppose it’s possible it could be monitored and could contribute to early warning systems. I worked for one of the companies that make up EarthScope for many years. While it might be helpful, the NSF grants are not set up for this purpose. Time to write another proposal, I suppose. They could call it EWWS (Early Weather Warning System). Why not? The project discussed here was called OIINK. I like EWWS.

  44. u.k.(us) says:

    TG McCoy (Douglas DC) says:
    March 9, 2012 at 10:43 am
    ==========
    Is English your first language, your spelling gives me great concern.
    As a former pilot, your posts don’t ring true.
    A true pilot, would give an emotional (filled with curses) response to my inquiry.
    Not a compilation of google searches.

  45. 1DandyTroll says:

    One report covering Harrisburg Ili, at MSNBC is logged at 2:57 am on the 29th of febuary and according to witness’ tornadoes in southern Illinois was on at 12:25 am already. That would be central for US not for europe.

    So, exactly how can they claim discovery to detect things going on at 4:45 am way after the fact for that area? It’s like stating after the crescendo of Katrina that there’s probably a storm having passed through here, and well, oh yeah, we kind of made that discovery.

    It’s probably more probable they detected the whif of one of the earth quakes couple states over that same morning then discovering a storm already passed.

  46. D. J. Hawkins says:

    Now if they added temperature and humidity sensors, an automatic rain gauge, and an annemometer, maybe we could get some high quality weather/climate info as well!!

  47. Galane says:

    Not surprising at all that tornadoes can cause ground movement detectable by seismology instruments, when they can do things like relocate entire buildings (not that the buildings *survive* the relocation) and scour away three feet of earth and carry away the 12 ton concrete top of a storm cellar, never to be found. (Probably dropped into a river or lake somewhere.)

    Saw that one on “Storm Stories” on The Weather Channel. Whomever built the shelter didn’t put rebar in the walls sticking up to cast the top around, figuring there was no way a twister could shift 12 tons of solid concrete covered by three feet of dirt. That family was lucky they didn’t make it to their storm shelter.

    That tornado would have caused some quite interesting seismograph readings.

  48. I’ve been through a few tornadoes in my 65 years, and don’t like them. I’ve seen them on weather radar and noticed the static interference on television screens (most notably on Channel 4). Tornadoes do weird things. I’d not be surprised that there would be a seismic signature for them any more than I’m not surprised there is an electrical and radar signature for them. This is something I’d be glad to follow for awhile. That’s the reason I love WUWT – you do it for me.

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