Global planetary ionization maps in Regener-Pfotzer cosmic ray maximum for GLE 66 during magnetic superstorm of 29–31 October 2003

• Published in: Advances in space research Vol. 70; no. 9; pp. 2593 - 2601
• Main Authors: Dorman, Lev I., Velinov, Peter I.Y., Mishev, Alexander
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-11-2022
• Subjects: Atmospheric ionization; Cosmic rays; Forbush effect; Ground level enhancement; Forbush effect; Atmospheric ionization; Ground level enhancement; Cosmic rays
• ISSN: 0273-1177; 1879-1948
• DOI: 10.1016/j.asr.2022.01.032

High-energy particles of cosmic origin e.g. cosmic ray protons and heavier nuclei of galactic and/or solar origin induce complicated nuclear-electromagnetic-meson cascades in the Earth’s atmosphere, eventually leading to an ionization of the ambient air. The induced by cosmic rays atmospheric ionization is related to possible effect of precipitating particles on atmospheric physics and chemistry. These effects can be considerably enhanced during strong and moderately strong solar proton events. While the contribution of galactic cosmic ray particles to ion production in the atmosphere is slightly variable throughout a solar cycle, relativistic solar particles could produce a significant excess on ion pair production, particularly over polar caps. This effect is strong on a short time scales. On the other hand, depressions of the galactic cosmic ray flux, that is, Forbush decreases, can significantly impact the galactic cosmic ray induced ionization. The sequence of three ground level enhancements observed in October-November 2003, specifically the second: GLE 66 which occurred during a giant Forbush decrease, provides unique opportunity to study impact ionization on extended time scale, explicitly considering the reduced galactic cosmic ray flux. Using Monte Carlo simulations we computed the ion production rate and the corresponding ionization effect in the Earth atmosphere during GLE 66 occurred on 29 October 2003, explicitly considering the Forbush decrease and the complex geomagnetospheric conditions.