EGUsphere

2568-6402

Copernicus Publications

Göttingen, Germany

10.5194/egusphere-2025-2340

Effect of Ionospheric Variability on the Electron Energy Spectrum estimated from Incoherent Scatter Radar Measurements

Stalder

Oliver

¹ Gustavsson

Björn

¹ Virtanen

Ilkka

https://orcid.org/0000-0002-7111-8888

Department of Physics and Technology, University of Tromsø, Norway

Space Physics and Astronomy research unit, University of Oulu, Finland

28 05 2025

2025 1 18

2025

This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/

This article is available from https://egusphere.copernicus.org/preprints/2025/egusphere-2025-2340/

The full text article is available as a PDF file from https://egusphere.copernicus.org/preprints/2025/egusphere-2025-2340/egusphere-2025-2340.pdf

The ion composition in the E-region is modified by auroral precipitation. This affects the inversion of electron density profiles from field-aligned incoherent scatter radar measurements to differential energy spectra of precipitating electrons. Here a fully dynamic ionospheric chemistry model (IonChem) is developed that integrates the coupled continuity equations for 6 ion and 9 neutral species, modeling the rapid ionospheric variability during active aurora. IonChem is used to produce accurate, time-dependent recombination rates for ELSPEC to improve the inversion of electron density profiles to primary electron energy spectra. The improvement of the dynamic recombination rates on the inversion is compared with static recombination rates from the International Reference Ionosphere (IRI) and the steady-state recombination rates from a ionospheric chemistry model, FlipChem. A systematic overestimation at high electron energies can be removed using a dynamic model. The comparison with FlipChem shows that short-timescale density variations are missed in a steady-state chemistry model