The aspects of K-index calculation at russian geomagnetic observatories

Abstract

One of the most widely used indices of geomagnetic activity is the K-index. It was proposed in 1938 by Julius Bartels as a measure of the influence of solar corpuscular radiation on the variations of the Earth’s magnetic field. Among the essential requirements to indices of this type is its stationarity, i.e., stability of the rules by which it is calculated. Therefore, despite the known disadvantages of the K-index, it is still being calculated according to the method, proposed by Bartels. Historically, at Russian geomagnetic observatories, the K-index has been calculated using simplified methods. In this paper we compare the K-index calculation routine at Russian observatories with the standard K-index and planetary Kp-index calculation technique.