Results of experimental determination of surface electromagnetic wave in natural conditions

Results of experiments for the observation of surface electromagnetic waves (SEWs) in the decameter range (10 and 15 MHz) excited by a vertical dipole and propagating above the ice-coated surface of a salt lake over a distance of up to 1.2 km are considered. It is shown that the SEW decays much more weakly than the “ground” ray. An analysis of the field of radiation from the vertical dipole reveals the presence of a wave with an amplitude decaying with the distance R approximately as 1/R^1/2, which corresponds to the SEW divergence. The absolute values of the radiation attenuation function |W| are significantly greater than unity and reach |W| = 2, which also corresponds to the SEW. Experimental data on the SEW damping agree with the results of numerical calculations of the electromagnetic field in the system under consideration.