author = "Abreu, Alessandro Jos{\'e} de and Martin, In{\'a}cio Malmonge 
                         and Jesus, Rodolfo de and Bolzan, Maur{\'{\i}}cio Jos{\'e} 
                         Alves and Venkatesh, Kavutarapu and Fagundes, Paulo Roberto and 
                         Alves, Mauro Angelo and Gende, Maur{\'{\i}}cio and Kumar, 
          affiliation = "{Instituto Tecnol{\'o}gico de Aeron{\'a}utica (ITA)} and 
                         {Instituto Tecnol{\'o}gico de Aeron{\'a}utica (ITA)} and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {Universidade Federal de Goi{\'a}s (UFG)} and {Universidade do 
                         Vale do Para{\'{\i}}ba (UNIVAP)} and {Universidade do Vale do 
                         Para{\'{\i}}ba (UNIVAP)} and {Instituto Tecnol{\'o}gico de 
                         Aeron{\'a}utica (ITA)} and {Universidad Nacional de La Plata 
                         (UNLP)} and {Banaras Hindu University}",
                title = "Comparison of GPS-TEC measurements with IRI2012-TEC predictions in 
                         the Brazilian sector during the unusual solar minimum 2009",
              journal = "Annals of Geophysics",
                 year = "2017",
               volume = "60",
               number = "3",
                pages = "A0331",
                month = "Jan.",
             abstract = "The total electron content (TEC) derived from two Global 
                         Positioning System (GPS) receivers localized at Palmas (PAL, 
                         10.2S, 48.2W, dip latitude 5.5S), near equatorial region, and 
                         S{\~a}o Jos{\'e} dos Campos (SJC, 23.2S, 45.9W, dip latitude 
                         17.6S), under the southern crest of the equatorial ionization 
                         anomaly (EIA), in the Brazilian sector are used in this paper. TEC 
                         from the latest available IRI-2012 model at the same locations is 
                         also used. A comparative study between GPS-TEC and the IRI-2012 
                         model is analyzed during the deep low solar activity period of 
                         2009 in the unusual solar cycle 23. The measurements and the 
                         modeled data show that the IRI-TEC model gives the better 
                         estimates of the GPS-TEC during the nighttime from January to 
                         December months at PAL and SJC. The IRI-TEC model shows larger 
                         differences from the GPS-TEC in the afternoon hours, mainly at 
                         SJC. These discrepancies observed at SJC in the afternoon hours 
                         for all months are possibly due to the dynamics of EIA in 
                         consequence of the equatorial fountain effect. At PAL and SJC, 
                         oscillations of GPS-TEC with periods around 16 days in April and 
                         periods around 27-32 days between September and December possibly 
                         are noticed which could be related to a modulation of the 
                         semidiurnal tide and Suns rotation, respectively. Also, 
                         oscillations with periods around 2-4 and 5-10 days from January to 
                         December are observed at PAL and SJC, possibly associated with the 
                         propagation of planetary waves.",
                  doi = "10.4401/ag-7300",
                  url = "http://dx.doi.org/10.4401/ag-7300",
                 issn = "1593-5213",
             language = "en",
           targetfile = "abreu_comparison.pdf",
        urlaccessdate = "24 jan. 2021"