Magnetosphere–Ionosphere–Ocean Coupling Under Solar Modulation: Rotational Stability as a Boundary Condition in the Earth–Moon System

This paper examines the Earth–Moon system within the framework of solar-modulated plasma dynamics, focusing on magnetosphere–ionosphere–ocean coupling. The central hypothesis is that long-term lunar tidal stabilization of Earth’s axial and rotational regime provides stable boundary conditions that influence large-scale ocean circulation and its electromagnetic interaction with the geomagnetic field. Because saline ocean water is conductive, oceanic motion through Earth’s magnetic field produces secondary induction effects that participate in magnetohydrodynamic (MHD) coupling. Solar wind variability modulates magnetospheric structure, ionospheric currents, and geomagnetic disturbances, which in turn interact with conductive ocean layers. The proposed framework integrates established gravitational mechanics, space physics, and geophysical fluid dynamics into a unified systems model in which rotational stability operates as a structural constraint on plasma–ocean–magnetosphere coupling efficiency.