www.ann-geophys.net/22/3211/2004/ doi:10.5194/angeo-22-3211-2004 © European Geosciences Union 2004 Response of the equatorial and low-latitude ionosphere during the space weather events of April 2002 1Centro Univ. Luterano de Palmas (CEULP), Universidade Luterana do Brasil (ULBRA), 77054-970 Palmas, TO, Brazil 2Universidade do Vale do Paraíba (UNIVAP), 12244-000 São José dos Campos, SP, Brazil 3Southwest Research Institute, San Antonio, TX 78238-5166, USA 4Instituto Nacional de Pesquisas Espaciais (INPE), 12201-970 São José dos Campos, SP, Brazil Abstract. A digital ionosonde, of the type known as Canadian Advanced Digital Ionosonde (CADI), has been in routine operation at São José dos Campos (23.2° S, 45.9° W; dip latitude 17.6° S), Brazil, since August 2000. A new CADI was installed at Palmas (10.2° S, 48.2° W; dip latitude 5.5° S), Brazil, in April 2002. The two CADIs are part of a new network being established in a collaborative program between UNIVAP and CEULP/ULBRA, to study the equatorial and low-latitude ionospheric regions in Brazil. In this paper we present and discuss the effects of the space weather events during 17-20 April 2002, as evidenced by the ionospheric parameter changes from simultaneous observations at São José dos Campos and Palmas. A comparison of the observed ionospheric parameters (h'F, hpF2 and foF2) at the two stations, separated only by about 1460km, shows both similarities and differences associated with the geomagnetic disturbances. Also, a comparison of the observed F-region parameters with the ASPEN-TIMEGCM model results is presented. The model results show reasonable agreement during the quiet period of observations, but some discrepancies have been observed during the geomagnetic disturbances. Full Article (PDF, 2518 KB) Citation: Lima, W. L. C., Becker-Guedes, F., Sahai, Y., Fagundes, P. R., Abalde, J. R., Crowley, G., and Bittencourt, J. A.: Response of the equatorial and low-latitude ionosphere during the space weather events of April 2002, Ann. Geophys., 22, 3211-3219, doi:10.5194/angeo-22-3211-2004, 2004. Bibtex EndNote Reference Manager XML |
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