Magnetic field induced by wake of moving body in wind waves

Abstract

A general procedure to evaluate the electromagnetic felds generated by moving seawater through the geomagnetic feld is proposed. It contains two essential steps: modeling of velocity vector of seawater according to its dynamic mechanism, and solution of Maxwell equations under a stratifed ocean confguration. Two kinds of motions are considered in this work, wind-driven waves and wakes due to a moving body. The ocean is taken to be infnitely deep at the moment. Both the velocity vector and magnetic feld are expressed as superposition of sinusoidal waves. Simulation results show that the magnetic felds produced by moderate wind waves or a typical size body moving at moderate speed are on the order of a few hundred pico-Tesla near the sea level. The spectrum characteristics of the two kind magnetic anomalies are distinct.