Unraveling the Eerie Enigma: Thousands Report Baffling 'Global Hum' Phenomenon
Thousands worldwide report hearing an incessant, low humming sound known as the “global hum” or “world hum,” a phenomenon first documented in the 1970s. Scientists explore various theories, including a unique form of low-frequency tinnitus, as its cause, while a website helps track its global presence. Coping strategies focus on acceptance to alleviate distress.
Imagine living with a constant, low humming sound that only you can perceive. This is the reality for thousands who report hearing a phenomenon often referred to as the “global hum” or “world hum.” This enigmatic sound has puzzled scientists and distressed individuals for decades, raising questions about its origin and prevalence.
The earliest documented accounts of the global hum surfaced in Bristol, England, during the 1970s, when local newspapers were inundated with letters from residents describing an incessant, low-frequency drone. Soon, similar reports emerged from various locations across the United Kingdom, Europe, North America, Australia, and New Zealand. Specific instances include humming sounds reported in Largs, Scotland, in the 1980s, and Whitehall, South Yorkshire, England, in 2001.
A particularly well-known case is the “Taos Hum” from 1993, when Catanya Salzman wrote to the Taos News, detailing how a persistent hum was disrupting her life and sleep. Her letter prompted an outpouring of similar testimonies from other Taos locals, many of whom had begun hearing the sound approximately a year prior. The widespread reports spurred New Mexico Representative Bill Richardson to commission a scientific investigation. A collaborative team from the Air Force’s Phillips Laboratory, Los Alamos, Sandia National Laboratories, and the University of New Mexico utilized advanced technology to measure the sound, yet its source remained a complete mystery.
In an effort to track and document the phenomenon, the Worldwide Hum Project website was launched in 2012. The site characterizes the classic description of the hum as resembling “a car or truck engine idling outside your home or down the block,” or a “low rumbling or droning sound.” It is typically perceived as being louder at night and indoors, and can often be masked by ambient background noise like a fan or radio. While many individuals who detect the sound claim to hear it continuously, the project also notes that some may be picking up on specific environmental sounds others cannot hear, leading to a perception of the hum only in particular locations or at certain times. The website aims to provide tools to differentiate between these two types of experiences.
Scientists have proposed numerous theories to explain the global hum. A study led by Norwegian University of Science and Technology (NTNU) professor Markus Drexl investigated 28 individuals experiencing the sound. Initial hypotheses, such as superior low-frequency hearing or the detection of natural inner ear noises, were not supported by the findings. Ultimately, the most compelling theory suggested that people hearing the hum might have a unique form of subjective tinnitus, specifically in the low-frequency range. Drexl stated, “Based on our results, although we haven’t ruled out cases of physical external sound sources, we suggest that subjective tinnitus in the low-frequency range is often the cause of hearing pulsations of low-frequency sound perceptions.” The researchers concluded that multiple factors likely contribute to why individuals hear the hum, explaining variations in its perception.
Beyond tinnitus, other scientific explanations have been floated. In 2015, French scientists theorized that the hum might be caused by the interaction of microseismic waves with seabeds, though this could not account for the sound’s intermittent nature for some hearers. Other suggestions include gas pipelines, wind, and electromagnetic frequencies. Meanwhile, conspiracy theories range from CIA activity to paranormal explanations involving aliens or ghosts.
Despite ongoing research, a complete understanding of the hum remains elusive. Drexl highlighted the knowledge gap in understanding how the auditory system processes low-frequency sounds or infrasound: “What we know about the hearing system is mainly based on how we capture and process sound with higher frequencies. We know less about how the auditory system handles and processes low-frequency sound, or infrasound. If we want to conduct a thorough assessment of low-frequency sounds and infrasound, we first need a better understanding of how sensory systems process low-frequency sound and infrasound.”
For those who experience the hum, it can be a source of significant distress. Kevin Fail, a bathroom installer from Durham, described it to the BBC in 2011 as “an overhead power line with this constant humming buzz.” Another hearer characterized it as “an endless riff of heavy metal music…difficult to say if felt or heard,” according to The Guardian. Dr. David Baguley, head of audiology at Addenbrooke's Hospital, suggests that acceptance is the best coping mechanism. He advises, “The more people focus on the noise, the more anxious and fearful they get, the more the body responds by amplifying the sound, and that causes even more upset and distress. It's a question of whether you tense up to the noise or are relaxed about it.”