Tdg. Clark, COMPUTER GENERATED K-INDEXES ADOPTED BY THE BRITISH-GEOLOGICAL-SURVEY, Journal of atmospheric and terrestrial physics, 54(3-4), 1992, pp. 447-456
On 1 January 1991 the British Geological Survey adopted a computer met
hod for generating K indices from its three geomagnetic observatories.
This replaced the traditional handscaling method, resulting in saving
of staff time. Other advantages are the ability to distribute K indic
es to users in real time and the fact that there will not be any chang
e in bias of the K index caused by a change of handscaler in future. T
he computer algorithm is described. The results of a comparison betwee
n the computed and handscaled K indices are presented, which show the
computer method to be compatible with handscaling.