On the influence of DC railway noise on variation data from Belsk and Lviv geomagnetic observatories

• Autorzy: Neska A. , Reda J. , Neska M. , Sumaruk Y.
• Języki publikacji: EN

Abstrakty

EN

Geomagnetic variation data from the observatories in Belsk (BEL, Poland) and Lviv (LVV, Ukraine) significantly suffer from disturbances caused by direct current (DC) electric railways. The aim of this study is to quantify the impact of these disturbances on quantities derived from such data, as the K index of magnetic activity and the induction arrow used in the geomagnetic deep sounding method to indicate lateral contrasts of elec- tric conductivity in the solid earth. Therefore, undisturbed data have been reconstructed by means of a frequency-domain transfer function that relates the horizontal magnetic field components of the observatory to the ones synchronously recorded at a noise-free reference station. The comparison of the K index derived from original and reconstructed data shows an increase of quiet time segments by 29 per cent for LVV and by 14 per cent for BEL due to our noise removal procedure. Furthermore, the distribution of the corrected K indices agrees well with the one from the Niemegk observatory in Germany

Słowa kluczowe

EN

geomagnetic observations; DC railway noise; induction arrows; K index

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2013
• Tom: Vol. 61, no. 2
• Strony: 385--403
• Opis fizyczny: Bibliogr. 19 poz.

Twórcy

autor

Neska A.

autor

Reda J.

autor

Neska M.

autor

Sumaruk Y.

• Institute of Geophysics, Polish Academy of Sciences, Warszawa, Poland,

Bibliografia

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