Open AccessA differencing method for the determination of the lunar daily geomagnetic variation from short data series
Author(s) -
Sellek R.
Publication year - 1981
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1981.tb02745.x
Subject(s) - earth's magnetic field , variation (astronomy) , series (stratigraphy) , geodesy , geology , data series , geophysics , mathematics , physics , astrophysics , magnetic field , econometrics , paleontology , quantum mechanics
Summary The measures of error associated with the lunar daily geomagnetic variation contain a contribution from non‐periodic variations present in the data. We eliminate some of these non‐periodic variations by taking differences between corresponding data from a pair of neighbouring recording stations. When only a short series of data is available for one of these stations, we show that it is possible to determine the lunar daily geomagnetic variation present in these data by combining lunar harmonic terms for the other, long‐running station with those calculated from the difference data. The lunar terms found by this method are all more precisely determined than those calculated by direct analysis. The validity of the method is confirmed by a test calculation.