For long-range surface-wave communications over seawater, what polarization is most effective?

The effectiveness of vertical polarization in long-range surface-wave communications over seawater is largely due to how electromagnetic waves interact with the surface of the water. Vertical polarization enables the radio waves to align with the vertical electric field, which allows for better coupling with the surface of the ocean. This characteristic leads to improved transmission and reception of signals across the horizon and contributes to longer propagation distances, as the waves can efficiently follow the curvature of the Earth while staying close to the surface.

Additionally, the horizontal polarization, while sometimes used, is less effective in this scenario because it does not couple as efficiently with the surface waves. The vertical orientation helps minimize reflections and losses that could occur at the water's surface, making vertical polarization the preferred choice for achieving optimal performance in these communication scenarios.