This paper presents the analysis of temporal variations of the geomagnetic field in the municipality of Macaé, Brazil. Current and historical magnetic field from the IGRF (International Geomagnetic Reference Field) and Gufm1 models were used to construct two-dimensional maps from 1590 to 2019. Analysis of the maps revealed that there was a large decrease in total magnetic field magnitude from around 48,000 nT in 1590 to 23,000 nT in 2019, i.e., a decrease of more than 50%. This decrease was interpreted as a direct influence of the east to west displacement of the South Atlantic Magnetic Anomaly (SAMA) in the last centuries.
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