Modelling regional electric field using EISCAT3D observations

by Habtamu W. Tesfaw (University of Oulu)

Here we present a data-driven regional model of the electric field based on the
EISCAT 3D observations, where measurements of the projected ion velocity in the
F-region  are fitted to a regional electric potential produced by a grid of
spherical elementary current systems. Performance of the model is demonstrated
using simulated ionospheric parameters obtained from the three-dimensional
GEMINI model.  Our model can be used either with multistatic or monostatic
measurements of the projected ion velocity. The model captures the ground truth
electric field including its complex spatial structure with average percentile
differences of about 1.5 %. Most accurate results are achieved with the
multistatic data, but the general spatial structure of the electric field can
be captured also with monostatic data, if optimal beam patterns and
regularization are used. The modeling method is also applied using real
monostatic LoS data measured by the Poker Flat ISR. The modeled electric field
shows reasonably well-behaved variations in latitude and longitude within the
radar’s field of view.