author = "Klipp, Telmo dos Santos and Petry, Adriano and Falc{\~a}o, 
                         Gabriel Sandim and Souza, Jonas Rodrigues de and Campos Velho, 
                         Haroldo Fraga de and Paula, Eurico Rodrigues de",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE)} and {Instituto Nacional de Pesquisas Espaciais (INPE)}",
                title = "Analysis of different total electron content maps over South 
                         America region",
                 year = "2018",
         organization = "Simp{\'o}sio Brasileiro de Geof{\'{\i}}sica Espacial e 
                         Aeronomia, 7. (SBGEA)",
             abstract = "A period of two years (2016-2017) of statistical analysis is 
                         presented for different ionospheric Total Electron Content (TEC) 
                         estimatives in South America region. Comparative analysis includes 
                         different sources of information: (a) vertical TEC maps derived 
                         using observations from a dense network of double frequency 
                         ground-based Global Navigation Satellite System (GNSS) receivers, 
                         (b) the International GNSS Service (IGS) vertical TEC maps and (c) 
                         ionosonde data from National Oceanic and Atmospheric 
                         Administration (NOAA) and National Institute for Space Research 
                         (INPE) sounding instruments. Analysis was based in computing 
                         differences between TEC values, which are accumulated in terms of 
                         Root Mean Square Error (RMSE) to produce time series plots and 
                         intensity maps. Ionosonde data was settled as a baseline for 
                         comparisons. Despite only 5 to 7 instruments are available at the 
                         same time for the period evaluated, they are relatively well 
                         spreaded over South America. TEC value for ionosondes is estimated 
                         using ionograms by accumulating electron densities in height using 
                         linear interpolation. The process of comparing TEC values is done 
                         by geographic and date/time best correspondences, although spatial 
                         resolution slightly differs for TEC maps (a) and (b) in relation 
                         to ionosondes locations (c). The daily analysis of TEC difference 
                         in terms of RMSE presented by (a) had overall better performance 
                         when compared to (b). However, both TEC maps show high RMSE values 
                         when compared to ionosondes, ranging from 2.5 to easily over 10 
                         TECU. The RMSE integrated over the whole 24 months period and 
                         grouped by the hour of the day shows that (a) and (b) perform 
                         better mostly in nocturnal period, and errors between the TEC maps 
                         are closer from 11 to 16 UTC.",
  conference-location = "Santa Maria, RS",
      conference-year = "05-09 nov",
             language = "pt",
           targetfile = "Livro_Resumos-VIISBGEA.pdf",
        urlaccessdate = "23 nov. 2020"