Strong space weather events are caused by the interaction of the Earth with emissions from the Sun.
The Sun continually streams out a solar wind consisting of charged particles, or plasma, traveling at high speeds throughout interplanetary space. The solar wind carries the solar magnetic field into space where it can interact with the magnetic field of planets like the Earth. Sometimes the solar wind gets particularly fast or turbulent and its magnetic field can trigger changes in the magnetic field and ionosphere of the earth. Let us have a look at some common types of space weather storms, what causes them, and how they impact the earth.
Radio Blackouts
Radio Blackouts are caused by bursts of X-ray and Extreme Ultra Violet radiation emitted from solar flares. Radio blackouts primarily affect High Frequency (HF) (3-30 MHz) communication, although fading and diminished reception may spill over to Very High Frequency (VHF) (30-300 MHz) and higher frequencies. The emissions ionize the sunlit side of the earth, which increases the amount of energy lost as radio waves pass through this region. Blackouts are by far the fastest to impact the earth. Usually, the radio blackouts last for several minutes, but they can last for hours. The impacts of Radio Blackouts are felt by industries relying on HF radio communication and low-frequency signals, primarily the marine and aviation industries.
Solar Radiation Storms
Solar radiation storms occur when large quantities of charged particles, electrons, and protons are accelerated by processes at or near the Sun. When these processes occur the earth's magnetic field and atmosphere offer only a little protection from this radiation. The polar regions are most affected by energetic particles because the magnetic field lines at the poles extend vertically downwards, allowing the particles to spiral down the field lines and penetrate into the atmosphere, increasing ionization. Solar radiation storm impacts include loss of HF radio communications through the polar regions, navigation position errors, elevated radiation exposure to astronauts, and to passengers and crew in aircraft at high altitudes and latitudes, and damage to satellite systems.
Geomagnetic Storms
Geomagnetic storms, strong disturbances to Earth's magnetic field, pose problems for many activities, technological systems, and critical infrastructure. The Earth's magnetic field changes in the course of a storm as the near-Earth system attempts to adjust to the jolt of energy from the Sun carried in the solar wind. Coronal Mass Ejections (CMEs) and their impact can disturb the geomagnetic field for days at a time. Geomagnetic storms induce currents that can have a significant impact on electrical transmission equipment. Electric power companies have procedures in place to mitigate the impact of geomagnetic storms.
It is very fascinating to know that each component of space weather impacts a different technology on earth.
