Over the reporting period, the project has made substantial progress in advancing modelling and data-assimilation capabilities for magnetosphere–ionosphere coupling. A key milestone was the publication of "How the Ionosphere Responds Dynamically to Magnetospheric Forcing" (Geophysical Research Letters, DOI:10.1029/2024GL108695). This study introduced a novel model that treats the magnetic field B and plasma velocity v as the primary variables ("B,v paradigm") rather than beginning with the electric field and currents ("E,j paradigm"). The model demonstrates how magnetospheric flow drives deformation of the ionospheric magnetic field via Faraday's law and provides a new physical interpretation of ground magnetic perturbations in terms of dynamic ionospheric coupling.
Building on this, a follow-up paper now available as an EGUsphere preprint (egusphere-2025-2051) extends the theoretical and numerical framework to more realistic geometries and parameter regimes. This represents an important step toward fully time-dependent treatment of ionospheric dynamics in magnetosphere-ionosphere simulations.
In parallel, the project contributed to NASA's Electrojet Zeeman Imaging Explorer (EZIE) mission, which was launched in March of 2025. EZIE will provide the first global measurements of auroral electrojets using the Zeeman effect. These data will be instrumental for investigating ionospheric dynamics in the DynaMIT project.
At the same time, major advances have been achieved in the development of the Local Mapping of Polar Ionospheric Electrodynamics (Lompe) technique. The original Lompe method (JGR Space Physics, DOI:10.1029/2022JA030356) introduced a flexible framework for combining ground and space-based observations into regional maps of ionospheric electrodynamics. Building on that foundation, a variant of Lompe (JGR Space Physics, DOI:10.1029/2024JA032744) expands the technique into three dimensions, enabling the reconstruction of volumetric current systems and field-aligned currents.
Collectively, these results represent a major step toward achieving DynaMIT's scientific objectives: moving from quasi-steady models of the ionosphere toward truly time-dependent, physically self-consistent representations of space–atmosphere coupling. The combination of theoretical advances and the forthcoming observational data establishes a foundation for the next phase of the project, in which the new framework will be validated and applied to key scientific questions.
