A comparison between effects of solar proton events and of geomagnetic storms on the ozone profiles

Abstract

Short-term variations along the ozone profiles (both in experimental and theoretical aspects) are discussed in the present work. Thus, a selected period of the major Solar Proton Event (SPE) of 14 July 2000, and the ensuing strong geomagnetic storm (K p=9o) with Sudden Storm Commencement (SSC) is investigated. This SPE is dubbed the “Bastille Event”, after the French national holiday. Ozone partial pressure measurements from the program Halogen Occultation Experiment (HALOE), realized by the Upper Atmosphere Research Satellite (LIARS) are used. The GOES-8 satellite obtains the data on high-energy protons. A statistical analysis of ozone and proton flux data is accomplished. The profiles of the stratospheric ozone in the above-mentioned selected period were constructed and the variations of the ozone density during the SPE with SSC were studied. A new model for the calculation of the ozone production rate (mol.cm −3.s −1) by relativistic and high-energy particles is applied. The method takes into account the law of particle energy transformation by penetration through the middle atmosphere. The ozone density increases in the height interval 15.5–18.5 km and decreases in the interval 24.5–35 km. Comparisons between experimental and theoretical ozone variations are made. On the basis of these comparisons and evaluations an interpretation of the possible mechanisms of stratospheric ozone response is given.