Earth-Potential Electrodes in Permafrost and Tundra

Describes installation at Point Barrow of two sets of electrodes to obtain earthpotential data for use in ionospheric studies. The first set, installed in a 6 x 6 ft excavation down to permafrost (12 in. in Aug. 1955) was five untreated electrodes, which became useless during the winter with resistances increasing by several orders of magnitude as ground temperatures dropped, a pronounced increase occurring below 0 F. A second set, installed in summer 1956 with sodium chloride incorporated in the fill, proved practical for recording earth potentials, maintaining resistances of less than 5,000 ohms throughout the winter.