High X-ray and UV radiation, high-energy particles or even plasma from coronary mass ejections hit the Earth during increased solar activity. Some of the effects on technologies are described below.

Radio blackout
The effect of X-rays from solar flares on the uppermost part of our atmosphere, the ionosphere, immediately leads to the loss of its ability to reflect long-range radio waves. The result is a (temporary) loss of all radio communication.

Interference with ground-based radio communication:
Similar to radio communication, the lower frequencies of the HF/KW band in radio traffic are also affected. They are sometimes even cancelled out (absorption), while on the other hand VHF/UHF can then generate a sometimes disruptive overreach. At the end of geomagnetic storms, it is often no longer the lower frequencies (as at the beginning) but the higher frequencies of the HF/CHF band that are unusable (depression). Interference can last for several hours during daylight hours. (DWD)

Satellite failure and interference
Today, we rely more and more on satellites for communications, navigation, passenger and freight transport and financial transactions. If we lose too many of these satellites in a geomagnetic storm, serious disruption can occur.

The high energy input as a result of the solar wind can heat up the upper atmosphere locally. As a result of increased temperature and density, the atmosphere then expands towards space, which in turn slows down or even destroys satellites. Technical systems on Earth are mainly affected in the northern hemisphere. In space, however, technical systems almost everywhere feel the full effects of solar flares and the subsequent geomagnetic storms. "There are currently 3,000 satellites operating in near space, and this number is expected to rise to 50,000 by the end of the decade," says Prof. Yuri Shprits, Head of the Space Physics and Space Weather Section at the GFZ Helmholtz Centre for Geosciences. "In the past, satellites were well shielded and made of special components that resist radiation. Many new satellites contain off-the-shelf components and we don't know how severe space weather can affect them."

In concrete terms, satellite damage means that navigation satellites could fail, which could bring global passenger and freight transport to a standstill. Moreover, the fact that the navigation satellites also set the Earth's time clock would lead to disruptions on the world's stock exchanges.

• Interference with global navigation satellite systems:
  •     GPS signals are slowed down when they pass through an ionosphere that is increasingly enriched with electrons during geomagnetic storms. Erroneous signal propagation times cause inaccurate positioning (without suitable correction data). Scintillations can occur near the equator (amplitude and/or phase shifts in the GPS signal). In some cases, GNSS signals are distorted to such an extent that they cannot be processed by the receiver, which can lead to fluctuations or even signal loss. (DWD)
• Interference with satellite-based communication:
  •     Solar flares and geomagnetic storms can cause strong scintillations (amplitude and/or phase shifts in the signal). The resulting signal attenuation can lead to a loss of connection. Such effects occur mainly in certain areas of the sky. (DWD)

Damage to the extra-high and high-voltage grid
Fractions of a second after the satellites, the earth is also hit by the charged particles. The extra-high and high-voltage grid and submarine cables in particular are affected by the unprecedented induced voltage peaks, as they mainly consist of overhead lines. Their transformers can burn out during solar storms and lead to the widespread failure of all power grids. In Germany, the high-voltage grid supplies regions with high consumption, for example the regions of large industry, large cities and rail transport.