Doppler Flash

Sudden eruption of electromagnetic radiation from the Sun, also known as a solar flares, alters the physical properties of the ionosphere, creating ionospheric perturbations, commonly referred to as a sudden ionospheric disturbance (SID). The ionosphere perturbation following a solar flare disrupts the over the horizon radio communication channels on the dayside of the Earth, also known as shortwave fadeout (SWF). The ionospheric radio wave absorption effect during a solar flare-driven SID is a well known and understood phenomena. However, the initial Doppler frequency shift, also known as “Doppler flash”, in the traveling radio wave is a newly discovered phenomena and not yet fully understood. This paper seeks to advance our understanding of the initial impacts of solar flares on the ionospheric properties.