Authors: De Abreu, Alessandro José; Martin, Inácio Malmonge; De Jesus, Rodolfo; Bolzan, Maurício José Alves; Venkatesh, Kavutarapu; Fagundes, Paulo Roberto; Alves, Mauro Angelo; Gende, Mauricio Alfredo; Kumar, Sanjay
Publication Date: 2017.
The total electron content (TEC) derived from two Global Positioning System (GPS) receivers localized at Palmas (PAL, 10.2°S, 48.2°W, dip latitude 5.5°S), near equatorial region, and São José dos Campos (SJC, 23.2°S, 45.9°W, dip latitude 17.6°S), 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 Sun’s 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.
Author affiliation: De Abreu, Alessandro José. Instituto Tecnológico de Aeronáutica; Brasil
Author affiliation: Martin, Inácio Malmonge. Instituto Tecnológico de Aeronáutica; Brasil
Author affiliation: De Jesus, Rodolfo. Centro de Previsao de Tempo e Estudos Climáticos. Instituto Nacional de Pesquisas Espaciais; Brasil
Author affiliation: Bolzan, Maurício José Alves. Universidade Federal de Goiás; Brasil
Author affiliation: Venkatesh, Kavutarapu. Universidade do Vale do Paraíba; Brasil
Author affiliation: Fagundes, Paulo Roberto. Universidade do Vale do Paraíba; Brasil
Author affiliation: Alves, Mauro Angelo. Instituto Tecnológico de Aeronáutica; Brasil
Author affiliation: Gende, Mauricio Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina
Author affiliation: Kumar, Sanjay. Banaras Hindu University; India
Repository: CONICET Digital (CONICET). Consejo Nacional de Investigaciones Científicas y Técnicas