The Effect of a Sloping Sea Floor on the Surface Electromagnetic Field

抄録

Plane electromagnetic waves are assumed to be incident normally on an ocean surface, overlying a sea floor of uniform slope. Berdichevskii's method of images is used to extend the computations of surface fields for a basement with non-zero conductivity, at sites remote from the coastline. The vertical magnetic field is enhanced over shallower depths while the horizontal electric field shows a transition from the polarization behaviour on the landward side of a continental shore to that on the seaward side. The fields are computed for slopes of 3° and 10° and compared with those over an ocean with a horizontal floor. The calculations are applied to three sets of measurements on iceislands in the Arctic Ocean; no disagreement is found, although quantitative explanation cannot be made owing to the difficulties of controlling the experimental conditions, or of simulating them precisely in a mathematical analysis.