Global Circulation of Martian Ionospheric Currents Revealed by Magnetometer Data

Abstract In the dynamo region of the Martian ionosphere, a large‐scale current is generated by charge separation: ions collide with neutrals while electrons preferentially gyrate around local magnetic field lines. Using MAVEN magnetometer data and a physics‐informed neural network constrained by Ampère's law and Gauss's law for magnetism (the Neural‐Curlometer technique), we compute the first continuous and locally‐resolved model of ionospheric currents. The reconstructed dynamo currents are concentrated between 125 and 220 km, with a Hall‐to‐Pedersen transition near 160 km. The current density scales with the crustal magnetic field, with a dayside correlation of 0.89, and is mostly active over regions where the crustal field ranges between 130 and 450 nT at 150 km. The proposed approach allows us to model the currents over time, revealing clear seasonal variability partially related to dust storm events. Furthermore, the modeled currents exhibit a smooth hemispheric vortex pattern consistent with independently predicted atmospheric wind circulation and Coriolis‐driven transport associated with seasonal condensation at the poles. As such, we provide a data‐driven proxy for atmospheric circulation at ionospheric altitudes, providing new inputs for Martian general circulation models.