Resumo:
n the last 60 years, the largest displacement of the magnetic equator (about 1100 km northwards) occurred in the Brazilian longitudinal sector. The magnetic equator passed by Tatuoca magnetic observatory (TTB, north of Brazil) in 2012 and continued to move northward. Since the total magnetic field is mostly horizontal in this region, enhanced electric currents in the ionosphere are produced - the so called equatorial electrojet (EEJ). The effect of EEJ is observed in the range of ± 3 degrees from the magnetic equator, where magnetic observatories record an amplified H-component signal. In order to track the spatial and temporal variation of this phenomena, a new magnetometer station was installed in Macapá (MAA), which is about 350 km northwest from TTB. In this thesis, I present the setup and data analysis of MAA station from 11/2019 until 09/2021. Because of its special configuration, we develop a method for temperature correction of the vector magnetometer data. The effect of amplified H-component caused by ionospheric currents in the Brazilian longitudinal sector is quantified by comparing MAA data with other observatories under and out of the EEJ influence.