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  2. Ionosphere - Wikipedia

    en.wikipedia.org/wiki/Ionosphere

    Lightning can cause ionospheric perturbations in the D-region in one of two ways. The first is through VLF (very low frequency) radio waves launched into the magnetosphere. These so-called "whistler" mode waves can interact with radiation belt particles and cause them to precipitate onto the ionosphere, adding ionization to the D-region.

  3. Ionospheric storm - Wikipedia

    en.wikipedia.org/wiki/Ionospheric_storm

    The effects of ionospheric storms on different layers in the ionosphere including in the F-region, E-region and D-region vary depending on the magnitude of the storm. F-Region is the most affected layer due to it ranging the highest altitude compared to the E-region and D-region.

  4. Sudden ionospheric disturbance - Wikipedia

    en.wikipedia.org/wiki/Sudden_ionospheric_disturbance

    A sudden ionospheric disturbance (SID) is any one of several ionospheric perturbations, resulting from abnormally high ionization/plasma density in the D region of the ionosphere and caused by a solar flare and/or solar particle event (SPE).

  5. Earth–ionosphere waveguide - Wikipedia

    en.wikipedia.org/wiki/Earthionosphere_waveguide

    The region between Earth's surface and the ionospheric D-layer behaves thus like a waveguide for VLF- and ELF-waves. In the presence of the ionospheric plasma and the geomagnetic field, electromagnetic waves exist for frequencies which are larger than the gyrofrequency of the ions (about 1 Hz). Waves with frequencies smaller than the ...

  6. Electron precipitation - Wikipedia

    en.wikipedia.org/wiki/Electron_precipitation

    When broadband very low frequency (VLF) waves propagate the radiation belts, the electrons exit the radiation belt and "precipitate" (or travel) into the ionosphere (a region of Earth's atmosphere) where the electrons will collide with ions. [2] Electron precipitation is regularly linked to ozone depletion. It is often caused by lightning strikes.

  7. Solar phenomena - Wikipedia

    en.wikipedia.org/wiki/Solar_phenomena

    A sudden ionospheric disturbance (SID) is an abnormally high ionization/plasma density in the D region of the ionosphere caused by a solar flare. The SID results in a sudden increase in radio-wave absorption that is most severe in the upper medium frequency (MF) and lower high frequency (HF) ranges, and as a result, often interrupts or ...

  8. Birkeland current - Wikipedia

    en.wikipedia.org/wiki/Birkeland_current

    Schematic of the Birkeland or Field-Aligned Currents and the ionospheric current systems they connect to, Pedersen and Hall currents. [1]A Birkeland current (also known as field-aligned current, FAC) is a set of electrical currents that flow along geomagnetic field lines connecting the Earth's magnetosphere to the Earth's high latitude ionosphere.

  9. Geomagnetically induced current - Wikipedia

    en.wikipedia.org/wiki/Geomagnetically_induced...

    The Earth's magnetic field varies over a wide range of timescales. The longer-term variations, typically occurring over decades to millennia, are predominantly the result of dynamo action in the Earth's core. Geomagnetic variations on timescales of seconds to years also occur, due to dynamic processes in the ionosphere, magnetosphere and ...