Three‐dimensional modeling of the electromagnetic characteristics of equatorial plasma depletions

We derive and employ an algorithm for the three‐dimensional fluid treatment of ionospheric plasma, including the complete set of electromagnetic fields. Traditionally, simulations of ionospheric plasma instabilities assume electrostatic physics and/or simplify the problem in two dimensions while the dynamics along the Earth's magnetic field lines are neglected. Explored are the 3‐D electric and magnetic fields resulting from current divergence, current flows, and Alfvén waves associated with low‐latitude plasma irregularity dynamics. We investigate both dynamic and static electromagnetic properties. For the first time, we present simulations of the Alfvénic dynamics that map electric fields along the Earth's magnetic field lines. We also find that 1‐D theory can significantly overestimate 3‐D ambipolar electric fields.