Electromagnetic response function for the semi-annual variations estimated by the single-station method using the night-time values of the geomagnetic fields

摘要: The geomagnetic night-time values were used to estimate the electromagnetic response function Q1 for half-year period. If spatial structure of source field can be described by P10 approximation, one value using single-station Z/H method. This technique enables us carry out regional deep sounding data analyses are about, typically, 26 years from 5 good-quality stations and several 34 distributed over globe. results indicate that yield more reliable estimates period compared usual obtained daily means. It implies approximation fields holds good period, but means not suitable estimating semi-annual variations Source have also been carried in this paper.