Improving Earth’s Magnetic Field Measurements by Numerical Corrections of Thermal Drifts and Man-Made Disturbances

Abstract EN

This contribution deals with challenges encountered in real-world geomagnetic measurements and is focused on improving the performance of two variometer stations of Kelčany and Polom, which have been recently established in the Czech Republic.

It is shown that a carefully designed full-field instrument, despite lacking temperature stabilization, can provide vectorial and scalar data accurate to a few nT, if the raw data were postprocessed by compensating for gain temperature coefficients—we show how this can be obtained by a precise calibration and long-term scalar measurements.

We also show a method for suppressing nT-level spikes in the data due to nearby car traffic, by utilizing gradiometric measurement for detecting the car occurrences and by employing a linear optimization problem in order to find the parameters of the moving magnetic dipole and compensate for it.

In this manner, we were able to reduce the anthropogenous noise due to car traffic while keeping as much original information as possible.