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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Equatorial ionization anomaly development as studied by GPS TEC and foF2 over Brazil: A comparison of observations with model results from SUPIM and IRI-2012

Texto completo
Autor(es):
Nogueira, P. A. B. [1] ; Abdu, M. A. [1] ; Souza, J. R. [1] ; Batista, I. S. [1] ; Bailey, G. J. [2] ; Santos, A. M. [1] ; Takahashi, H. [1]
Número total de Autores: 7
Afiliação do(s) autor(es):
[1] Inst Nacl Pesquisas Espaciais, Div Aeron, BR-12227010 Sao Paulo - Brazil
[2] Univ Sheffield, Sheffield, S Yorkshire - England
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS; v. 104, p. 45-54, NOV 2013.
Citações Web of Science: 7
Resumo

The equatorial ionization anomaly (EIA) development is studied using the total electron content (TEC) observed by the Global Positioning System (GPS) satellites, the F2-layer critical frequency (foF2) as measured by digisondes operated in the Brazilian sector, and by model simulation using the SUPIM (Sheffield University Plasmasphere Ionosphere Model). We have used two indices based on foF2 and TEC to represent the strength of the EIA Southern Anomaly Crest (SAC), which are denoted, respectively, by SAC(foF2) and SAC(TEC). Significant differences in the local time variations of the EIA intensity, as represented by these two indices, are investigated. The observed SAC indices are compared with their values modeled by the SUPIM and also by the International Reference Ionosphere (IRI)-2012. The SUPIM simulations that use the standard E x B plasma drift and neutral air wind models are found to provide acceptable representations of the observed foF2 and TEC, and hence the indices SAC(foF2) and SAC(TEC) during daytime, whereas the IRI-2012 model is not, except during the post-midnight/sunrise hours. It is found that the differences in the local time variations between the SAC(foF2) and SAC(TEC) can be reduced by limiting the TEC integrations in height up to an altitude of 630 km in the SUPIM calculations. It is also found that when the EIA intensity is calculated for an intermediate dip latitude (12 degrees S) the difference between the local time variation patterns of the two corresponding indices in the experimental data and in the SUPIM results is reduced. For the IRI-2012 values, the subequatorial station modification does not appear to have any effect. (C) 2013 Elsevier Ltd. All rights reserved. (AU)

Processo FAPESP: 13/01924-1 - Estudo e Previsão do Conteúdo Eletrônico Total na Região da América do Sul.
Beneficiário:Paulo Alexandre Bronzato Nogueira
Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado