Solar cycle 22 control on daily geomagnetic variation at Terra Nova Bay (Antarctica)

• Published in: Annals of Geophysics
• Main Authors: Cafarella, L., Meloni, A., Palangio, P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Istituto Nazionale di Geofisica e Vulcanologia, INGV 1998
• Subjects: magnetic variations; daily variation; Antartica; 01.03.05. Solar variability and solar wind; Terra Nova Bay; Antarc*; Antarctica; antartic*
• Online Access: https://www.annalsofgeophysics.eu/index.php/annals/article/view/3820; https://doi.org/10.4401/ag-3820

Nine summer geomagnetic observatory data (1986-1995) from Terra Nova Bay Base, Antarctica (Lat.74.690S, Long. 164.120E, 80.040S magnetic latitude) are used to investigate the behaviour of the daily variation of the geomagnetic field at polar latitude. The instrumentation includes a proton precession magnetometer for total intensity |F| digital recordings; DI magnetometers for absolute measuring of the angular elements D and I and a three axis flux-gate system for acquiring H,D Z time variation data. We find that the magnetic time variation amplitude follows the solar cycle evolution and that the ratio between minimum solar median and maximum solar median is between 2-3 for intensive elements (H and Z) and 1.7 for declination(D). The solar cycle effect on geomagnetic daily variation elements amplitude in Antarctica, in comparison with previous studies, is then probably larger than expected. As a consequence, the electric current system that causes the daily magnetic field variation reveals a quite large solar cycle effect at Terra Nova Bay.