Reevaluation of EISCAT plasma parameters during the May 2024 geomagnetic storm using O+ ratios from AMIE-driven SD-WACCM-X

Kurzfassung

Inferring Level 2 plasma parameters from incoherent scatter radar mea surements requires a priori assuming certain quantities. Previous studies suggested that the ratio of atomic oxygen ions (O+) is the parameter with the largest impact on the inferred plasma parameters, and especially under geomagnetic storm conditions, the applied IRI ion composition deviates from realistic conditions. Several approaches to this problem have been investigated in the past, and we present a new approach, making use of a data assimilative geomagnetic forcing technique (AMIE). We apply O+ ratios given by an AMIE-driven WACCM-X model run of the May 2024 geomagnetic storm for a reevaluation of the EISCAT Svalbard Radar measurements of this event. We show that the level 2 parameters are altered by up to 15% (electron density) and 40% (ion and electron temperatures) in this reevaluation. The possibility of an empirical correc tion model is discussed.