Total Electron Content Monitoring over South America Region: Validation and Case Studies

Abstract:

The Total Electron Content (TEC) is being extensively used to monitor the ionospheric behavior under geomagnetically quiet and disturbed conditions. The complex effects of magnetospheric convection and geomagnetic disturbances on ionospheric electric fields and currents in middle and low latitudes were documented in several studies. Under disturbed conditions the two main sources of electric fields, which are responsible for changes in the plasma drifts and for current perturbations, are the short-lived prompt penetration electric fields (PPEFs) and the longer lasting ionospheric disturbance dynamo (DD) electric fields, and both modulate the TEC around the globe. In this work we present the validation of a computational tool to calculate TEC maps over the low latitude of South America region. We used two methods to calculate the absolute VTEC: TECMAP-Nagoya tool and Magic (NOAA) tool. Their results were compared to the TEC measured by an Allen Osborne receiver placed at São José dos Campos (Brazil) and show a good agreement. The results were performed considering quiet and disturbed conditions, and also HILDCAAs events. Data from the RBMC/IBGE (Brazil), IGS and RAMSAC (Argentina) networks were used to calculate TEC over the South America. The expansion of RBMC and RAMSAC networks is providing a good coverage and understanding of TEC behavior at this complex low latitude region.