The Diamagnetic Layer of the Earth's Atmosphere and Its Relation to The Diurnal Variation of Terrestrial Magnetism

Abstract

Anisotropic conductivity of upper atmosphere due to presence of earth's magnetic field.—An investigation of the motion of ions and electrons in the region of long free paths shows that the electrical conductivity in the direction of the earth's magnetic field is that predicted by simple theory. The conductivity in a direction at right angles to the magnetic field and in the direction of the applied electric field is zero while the pseudo conductivity at right angles to both is finite and the mechanism such that ions of both kinds are swept in the same direction. As a consequence of this situation it appears that large circulating currents in the upper atmosphere of the type assumed in present theories of the diurnal terrestrial magnetic variations are hardly possible.