Noise that can’t be escaped:

Data Proves That Effort To Quiet O’Hare Night Skies Working Only About Half The Time.  DNAinfo.com reports that “[p]lanes landed and took off as promised 57 percent of the time during the first eight weeks of a test to rotate the O’Hare Airport runways used at night to give Northwest Side residents some relief from jet noise.”  Apparently summer storms required air traffic controllers to divert from the plan, not allowing them to use runways that were supposed to keep certain areas quieter.

The reason for the test is that some residents complained that it was “impossible to get an uninterrupted night of sleep since an east-west runway opened in 2013.”  In response, the airport has implemented “voluntary restrictions on nighttime operations at O’Hare, known as Fly Quiet, [which] encourage pilots and air traffic controllers to fly over expressways, industrial areas and forest preserves to reduce the noise over residential areas from 10 p.m.-7 a.m.”  How nice.  And yet:

Chicago Aviation Commissioner Ginger Evans has touted the rotation as a “big breakthrough” in city efforts to reduce the jet noise that prompted more than 4 million complaints in 2015. (emphasis added)

4 million jet noise complaints in one year.

Each element of noise in today’s world apparently stands on its own.  Eventually people will have to recognize that all noise is noise and must be regulated in a fair manner so that people can sleep, think, and function.  Keep an eye on this site, because help is coming.

Comments (2)

  1. Raymond MacDonald

    Infrasound

    An article in The Mercury News (see citation below) cites the findings of Jon Hagstrum of the US Geological Survey on his work “infrasound”
    “Humans can’t hear infrasound, but birds can. These very low-frequency acoustic waves come from different natural sources, but particularly the subtle tremors of the Earth’s crust — so each part of the planet has its own distinct “sonic signature.” And these infrasonic sounds travel thousands of miles, far longer than ordinary sound waves.”
    Terms / References

    • Infrasound
    See definition, citation details below…
    https://en.wikipedia.org/wiki/Infrasound

    • bioacoustics
    i.e., the impact of aircraft, ship and roadway noise on animals/nature (like migrating birds and whales). We know about the work of Jesse Barber and others, but this is the first I’ve read about infrasound as the navigational capability that can be disrupted by noise that is below the threshold of hearing by humans.

    • Bioacoustics Research Program
    Cornell Lab’s Bioacoustics Research Program (BRP)
    http://www.birds.cornell.edu/brp/

    • The Quiet Coalition
    https://www.silencity.com/category/the-quiet-coalition/

    Articles:

    • USGS scientist proposes that migrating birds ‘hear’ their way home
    The Mercury News, By LISA M. KRIEGER | lkrieger@bayareanewsgroup.com | Bay Area News Group
    April 1, 2011 at 10:10 am

    Excerpt:
    “Humans can’t hear infrasound, but birds can. These very low-frequency acoustic waves come from different natural sources, but particularly the subtle tremors of the Earth’s crust — so each part of the planet has its own distinct “sonic signature.” And these infrasonic sounds travel thousands of miles, far longer than ordinary sound waves.”

    “They are imprinting on the characteristic sound” of where they live, he told a crowd this week at a lecture at USGS headquarters in Menlo Park. “The terrain has characteristic frequencies. I think that is the sound they are listening to.”

    “The most infamous incident took place on June 29, 1997, at a celebration of Britain’s Royal Pigeon Racing Association’s 100th anniversary. More than 60,000 trained birds — the best of the best — were released from southern France. Then, the crowd anxiously awaited their arrival home in southern England.

    Just a few thousand of the birds were ever seen again.

    What happened? Pigeon fanciers fear losing one or two birds, but tens of thousands?
    Hagstrum noticed a curious coincidence. That same morning, the Concorde supersonic transport plane was flying across the English Channel en route to New York from Paris. But its departure time was 8:30 a.m. — far earlier than the bird’s 10 a.m. release time.”

    Source:
    http://www.mercurynews.com/2011/04/01/usgs-scientist-proposes-that-migrating-birds-hear-their-way-home/

    ——
    “A scientist working at Sydney University’s Auditory Neuroscience Laboratory reports growing evidence that infrasound may affect some people’s nervous system by stimulating the vestibular system, and this has shown in animal models an effect similar to sea sickness”.[35]

    ——
    Infrasound (source)
    definitions, citations from Wikipedia
    https://en.wikipedia.org/wiki/Infrasound

    o “Animal communication: whales, elephants,[11] hippopotamuses,[12] rhinoceros,[13][14] giraffes,[15] okapi,[16]and alligators are known to use infrasound to communicate over distances—up to hundreds of miles in the case of whales. In particular, the Sumatran Rhinoceros has been shown to produce sounds with frequencies as low as 3 Hz which have similarities with the song of the humpback whale.[14]

    o The roar of the tiger contains infrasound of 18 Hz and lower,[17] and the purr of felines is reported to cover a range of 20 to 50 Hz.[18][19][20]It has also been suggested that migrating birds use naturally generated infrasound, from sources such as turbulent airflow over mountain ranges, as a navigational aid.[21]

    o Infrasound also may be used for long-distance communication, especially well documented in baleen whales (see Whale vocalization), and African elephants.[22] The frequency of baleen whale sounds can range from 10 Hz to 31 kHz,[23] and that of elephant calls from 15 Hz to 35 Hz. Both can be extremely loud (around 117 dB), allowing communication for many kilometres, with a possible maximum range of around 10 km (6 mi) for elephants,[24] and potentially hundreds or thousands of kilometers for some whales.[citation needed]

    o Elephants also produce infrasound waves that travel through solid ground and are sensed by other herds using their feet, although they may be separated by hundreds of kilometres. These calls may be used to coordinate the movement of herds and allow mating elephants to find each other.[citation needed]”

    o “Animals have been known to perceive the infrasonic waves going through the earth by natural disasters and can use these as an early warning. A recent example of this is the 2004 Indian Ocean earthquake and tsunami. Animals were reported to flee the area hours before the actual tsunami hit the shores of Asia.[29][30] It is not known for sure that this is the cause; some have suggested that it may have been the influence of electromagnetic waves, and not of infrasonic waves, that prompted these animals to flee.[31]

    o Research in 2013 by Jon Hagstrum of the US Geological Survey suggests that homing pigeons use low-frequency infrasound to navigate”.[32]

    o Human singers: some vocalists, including Tim Storms, can produce notes in the infrasound range.[25]

    Human created sources:
    o Infrasound can be generated by human processes such as sonic booms and explosions (both chemical and nuclear), or by machinery such as diesel engines, wind
    o turbines and specially designed mechanical transducers (industrial vibration tables). Certain specialized loudspeaker designs are also able to reproduce extremely low frequencies; these include large-scale rotary woofer models of subwoofer loudspeaker,[26] as well as large horn loaded, bass reflex, sealed and transmission line loudspeakers.[27][28]

    Animal reactions
    See also: P-wave

    o Animals have been known to perceive the infrasonic waves going through the earth by natural disasters and can use these as an early warning. A recent example of this is the 2004 Indian Ocean earthquake and tsunami. Animals were reported to flee the area hours before the actual tsunami hit the shores of Asia.[29][30] It is not known for sure that this is the cause; some have suggested that it may have been the influence of electromagnetic waves, and not of infrasonic waves, that prompted these animals to flee.[31]

    o Research in 2013 by Jon Hagstrum of the US Geological Survey suggests that homing pigeons use low-frequency infrasound to navigate.[32]

    Human reactions

    o 20 Hz is considered the normal low-frequency limit of human hearing. When pure sine waves are reproduced under ideal conditions and at very high volume, a human listener will be able to identify tones as low as 12 Hz.[33] Below 10 Hz it is possible to perceive the single cycles of the sound, along with a sensation of pressure at the eardrums.

    o From about 1000 Hz, the dynamic range of the auditory system decreases with decreasing frequency. This compression is observable in the equal-loudness-level contours, and it implies that even a slight increase in level can change the perceived loudness from barely audible to loud. Combined with the
    natural spread in thresholds within a population, its effect may be that a very low-frequency sound which is inaudible to some people may be loud to others.

    o One study has suggested that infrasound may cause feelings of awe or fear in humans. It has also been suggested that since it is not consciously perceived, it may make people feel vaguely that odd or supernatural events are taking place.[34]

    o A scientist working at Sydney University’s Auditory Neuroscience Laboratory reports growing evidence that infrasound may affect some people’s nervous system by stimulating the vestibular system, and this has shown in animal models an effect similar to sea sickness.[35] In a study of 45 people, Tehran University researchers stated: “Despite all the good benefits of wind turbines … this technology has health risks for all those exposed to its sound” — in particular, sleep disorder.

    o In a study at Ibaraki University in Japan, researchers said EEG tests showed that the infrasound produced by wind turbines was “considered to be an annoyance to the technicians who work close to a modern large-scale wind turbine.”[36][37][38]

    Source: https://en.wikipedia.org/wiki/Infrasound

    Reply
    1. GMB (Post author)

      Thank you. This discussion is fascinating.

      Reply

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