ELECTRODYNAMICS IN A ROTATING-FRAME OF REFERENCE WITH APPLICATION TO GLOBAL OCEAN CIRCULATION

The electrodynamic equations in a rotating reference frame (with veloc ities of rotation much less than the speed of light) are derived for t he cases of a medium stationary in the rotating frame, and a medium wi th a general velocity relative to the rotating frame. The second case is considered as a necessary formalism for use in the modelling of lar ge-scale electromagnetic fields induced by a prescribed ocean circulat ion. The terms that include rotational effects depend not only on the relative velocities but also on the electric properties of the materia l media. Hence, the assumption that rotational terms can be neglected simply because the velocities involved are much less than that of ligh t in a vacuum is not supported. For typical values of the parameters d escribing the electric properties of the ocean, three of the four Maxw ell equations (in Minkowskian form) are similar in form to those in an inertial frame. A governing induction equation in one vector variable (the magnetic field, b) is derived and written out explicitly in vari ous coordinate systems.