The Earth sings whistles and talks to us all the time. And scientists are still trying to understand everything the Earth is saying to us. Not only does the Earth sing and whistle to us but also puts on beautiful light shows for us at the same time.
The Dawn Chorus
The song the Earth sings to us is known as the “dawn chorus” and the light show is the Aurora Borealis or the Australis Borealis, the northern and southern lights.
Several times a month, usually starting at sunrise until mid-morning, the Earth is singing to us, the dawn chorus.
At time it sounds like flocks of birds chirping and other times it can sound like hundreds of people whistling in rising and dropping tones. Once in awhile the song is eerie with hisses of different pitches and sliding tones, which stop and then start all over again.
What actually is causing the dawn chorus is the sound of high-energy particles from the sun as they hit the Earth’s Van Allen radiations belts, usually during times of active or high solar activity.
Doesn’t it seem the scientific explanation isn’t as fun as the imagination, but you can still imagine this is the Earth’s way of singing to us.
The dawn chorus is what is occurring as the sun ejects particles at a high rate of speed towards the Earth, and these particles interact with the magnetic fields of the planet causing these sounds to be heard in the radio spectrum.
The dawn chorus can be heard in the ELF (extremely low frequency) and the VLF (very low frequency) ranges of the radio spectrum. To put some mystery back in, the dawn chorus doesn’t always occur during times of high solar activity, so all of the reasons aren’t yet known for this interesting phenomena.
What Are Whistlers
The Earth also whistles to us, and the accompanying light show this time is lightning. At any given moment there are an estimated 2,000 thunderstorms occurring and an estimated 100 lightning strikes every second on the Earth.
This creates a huge amount of electromagnetic energy all around the planet and can be heard in the ELF portion of the radio spectrum.
When a lightning strike occurs, it causes sferics, which is short for atmospherics. Sferics is the normal crackle and hiss you hear on an AM radio when there is a nearby thunderstorm.
Tweeks are also sferics that travel much further in distance than normal lightning static or sferics. A tweek sounds like a short musical ricochet.
Whistlers are caused also caused by lightning strikes and travel much further distances.
A whistler is a burst of radio energy that sounds like a whistle falling in pitch and is initiated with a lightning strike. Whistlers can last a second or longer.
The Earth Talks to Us
The Earth also talks to us sometimes accompanied by an eerie light show. A new science of listening to the Earth talk to us is gaining popularity among scientists who believe the Earth emits electromagnetic waves before an earthquake strikes.
The theory is that electromagnetic pulses in the crust of the planet or disturbances in the ionosphere are caused by the fracturing of rocks before an earthquake and these rocks contain magnetic particles.
These disturbances have occurred as much as two weeks before the main earthquake. Sometimes before a major earthquake, people have reported seeing lights in the sky. These lights could be electromagnetic disturbances caused by the fracturing of these magnetic rocks.
These strange lights were seen in China before the large earthquake of May 12, 2008 in Sichuan, China. Hours before a 6.9 earthquake stuck Kobe, Japan there were 23 reported sightings of strange lights in the sky.
Researchers at Stanford University noticed disturbances in the ELF radio band weeks before the 1989 San Francisco/Oakland (World Series) earthquake. You can see the strange lights 30 minutes before the Sichuan earthquake in the following YouTube video.
You can build your own ELF receiver and listen for these sounds but in the city the manmade noise usually drowns them out. A better way to hear the dawn chorus and whistlers would be to listen to recordings.
Facts About the Van Allen Belt
The Van Allen belt is a belt of electrically charged particles around the Earth at an altitude of about 4,000 miles (6,400 km), which are trapped and held in place by the Earths magnetic field.
The Earth actually has two and possibly three radiation belts. The inner belt is the Van Allen belt, named after its discoverer, Dr. James Van Allen of the University of Iowa.
© 2009-2014 Sam Montana
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