Northern European nations have this year been complaining of unexplained ‘outages’ of vital GPS systems. Now we know it was actually a secret experiment with the Chinese to modify the Earth’s atmosphere — to boost and jam vital signals.

Scientists have revealed the existence of the project in a research paper published in the Chinese journal Earth and Planetary Physics.

According to the South China Morning Post, it describes how a specific layer of the Earth’s atmosphere over Europe was ‘modified’ to test the military application of the technology.

The interaction of the sun and cosmic rays with Earth’s atmosphere and magnetic sphere creates a variable layer of free-floating, positively charged ions some 75km to 1000km above the surface. This layer reflects radio waves, enabling transmissions such as short-wave radio and some radars to travel long distances.

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Depending on its state due to ‘space weather’ — such as solar storms — it can also serves as a barrier to signals attempting to pass through it.

“The militaries have been in a race to control the ionosphere for decades,” the South China Morning Post asserts.

Reportedly, a 500km-high portion of the ionosphere was ‘heated’ five times in June. One test, on June 7, caused some 126,000 sqkm of the sky — roughly equivalent to half the size of Britain — to flare with energy.

Whether or not similar experiments caused a series of GPS failures during NATO’s Trident Juncture military exercise in the North Atlantic in October and November is not known.

An ex Soviet Union facility near the central Russian town of Vasilsurk was modified for the test. Called Sura, the array of high-power transmittion towers pumped microwaves high into the sky.

At its peak output of 260 megawatts (enough for a small city), it was reportedly able to manipulate the temperature of a thin layer of ionised gas in the outer reaches of our atmosphere by up to 100C.

The effect of the Russian transmitters was measured by a Chinese electromagnetic surveillance satellite, Zhangheng-1.

The research team reported the results to be “satisfactory”.

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It states even relatively low outputs of microwave power could create large ‘abnormalities’ in the ionosphere. But it was only effective at night, as the sun’s influence quickly overwhelmed the artificial output.

“The detection of plasma disturbances … provides evidence for likely success of future related experiments,” the study reads.

The Post adds: “High-energy microwaves can pluck the electromagnetic field in ionosphere like fingers playing a harp. This can produce very low-frequency radio signals that can penetrate the ground or water — sometimes to depths of more than 100 metres in the ocean, which made it a possible communication method for submarines.”

Russia is not the only nation with such technology. The United States operates a similar array in Alaska. Australia’s Jindalee/JORN over-the-horizon radar system also relies on the ionosphere to bounce signals back and forth.

China is now reportedly building a larger transition array in Sanya, Hainan, “with capability to manipulate the ionosphere over the entire South China Sea”.