The Earth has been the focus of a massive amount of scientific study over the years. From the shrinking ozone layer to the changes in our planet's magnetic field, there's plenty to keep researchers busy.
One possibly surprising area of research is in the way in which the Earth acts like a giant electrical circuit. The atmosphere of the Earth is actually a weak conductor. If there was no source of electric charge for the atmosphere, its energy would dissipate in about 10 minutes — but it doesn't.
The ionosphere is the region of the Earth's atmosphere that stretches roughly from 30 to 620 mi (50-1,000 km) above the surface and, along with the upper atmosphere, forms a boundary between Earth's lower atmosphere and the vacuum of space.
Due to solar radiation, individual electrons are dislodged from otherwise neutral gas atoms in this region, creating positively charged ions. This makes the ionosphere conductive and able to trap electromagnetic waves.
Between the Earth's surface and the ionosphere is a cavity containing a total electrical charge of 500K Coulombs. There is a vertical current flow between the ground and the ionosphere. The atmosphere has a resistance of 200 Ohms and a voltage potential of 200,000 Volts.
Around the Earth, there are roughly two thousand lightning storms at any given period of time, producing around 50 flashes of lightning every second. This accounts for much of the measured flow in this electromagnetic cavity.
But what does all this mean?
It means that there is a great deal of electrical activity between the surface of the Earth and the ionosphere. Some of this is in the form of standing waves of electricity. These standing waves are known as Schumann Resonances. So what are these resonances?
Each lightning burst creates electromagnetic waves that begin to circle Earth in the cavity between Earth's surface and the ionosphere. Some of the waves — if they have just the right wavelength — combine and increase in strength to create a Schumann resonance.
The 'sweet spot' for creating this resonance is when the wave is as long or longer than the circumference of Earth. This is an extremely low-frequency wave of up to one hundred thousand times lower than the lowest frequency radio waves used to send signals to your AM/FM radio. As this wave flows around Earth, it hits itself again in such a way that the crests and troughs of the wave are aligned and act in resonance with each other to increase the original signal.
Scientists speculate that the waves are related to the electrical activity in the atmosphere.
The base atmospheric electromagnetic resonant frequency is 7.83 Hz. This means our atmosphere is continuously resonating with a radio frequency of 7.83 Hz, along with progressively weaker harmonics at around 14.3, 20.8, 27.3, and 33.8 Hz. These oscillations are called the Schumann resonances.
The atmosphere was first proposed as a good conductor of electricity in 1893 by George FitzGerald. He was able to estimate that, based on the layers of the atmosphere where he saw the best conductors, there would be electromagnetic oscillations of around 0.1 seconds. He had theorized and essentially discovered the lowest mode of Schumann resonances.
Although it has been suggested that the resonances be renamed Schumann-Fitzgerald, his findings weren't well known and received little scientific discussion at the time.
It wasn't until 1902 that it was suggested the ionosphere existed, and in 1925, the existence of the ionosphere was experimentally proven.
Although mathematical tools for dealing with spherical waveguides were developed in 1918 by G. N. Watson, the theoretical aspects of global resonances were not substantively studied before Winfried Otto Schumann's work in 1952-1954.
Schumann, working with H. L. König, was the first to attempt to measure the resonant frequencies of the Earth. However, it was not until 1963 that some techniques were developed for extracting the exact resonance frequencies from background noise.
What does a spike mean?
The amount of resonance fluctuates as the ionosphere becomes more or less dense. This depends largely on the amount of solar radiation striking it. At night, that part of the ionosphere that's in the Earth's shadow thins out.
The resonance can also be affected by the world's three lightning hotspots — Asia, Africa, and South America, which are seasonal and also follow a day/night cycle. Thus, the peaks of radio signal strength at the Schumann resonance follow a constantly shifting but reasonably predictable schedule.
It has also become common for some to associate the Schumann frequencies with different types of brain wave states. Some have even gone as far as to relate the frequency of 7.83 Hertz to hypnosis, suggestibility, meditation, and an increase in human growth hormones. However, there is no scientific proof for any of this.
Whether it's quackery or not is still being researched, but there are some researchers who believe that our bodies can be influenced by the electromagnetic resonant frequencies around us.
So when these frequencies spike, these people believe this can also have an effect on human and animal behavior.
In January of 2017, the Schumman resonance reached frequencies of above 36 Hz, which was unusual. Historically any rise above 15 Hz was considered large, so scientists were puzzled. According to some, these higher resonant frequencies on Earth are associated with more stressed nervous systems than normal.
In the realm of "speculative" or "new age science," many believe that the Schumann Resonance can be affected by and affect human consciousness. So, according to this theory, if there is a global increase in anxiety or tension, this will also affect the Schumann Resonance.
There's also the belief among some New Age proponents that an increase in these resonant frequencies could affect humanity as a whole and cause a global rise in anxiety, tension, and/or passion.
Although these ideas can be dismissed as having no basis in science, there is still a question of whether the Earth's electromagnetic fields can have an effect on humans.