Articles | Volume 31, issue 12
Regular paper 03 Dec 2013
Regular paper | 03 Dec 2013
Statistical analysis of radar observed F region irregularities from three longitudinal sectors
R. Y. C. Cueva et al.
No articles found.
Neelakshi Joshi, Reinaldo R. Rosa, Siomel Savio, Esfhan Alam Kherani, Francisco Carlos de Meneses, Stephan Stephany, and Polinaya Muralikrishna
Ann. Geophys., 38, 445–456,
Telmo dos Santos Klipp, Adriano Petry, Jonas Rodrigues de Souza, Eurico Rodrigues de Paula, Gabriel Sandim Falcão, and Haroldo Fraga de Campos Velho
Ann. Geophys., 38, 347–357,
Jonas Sousasantos, Alison de Oliveira Moraes, José H. A. Sobral, Marcio T. A. H. Muella, Eurico R. de Paula, and Rafael S. Paolini
Ann. Geophys., 36, 565–576,Short summary
This work presents an analysis of the scintillation onset over the southern Brazil based on data from two solar maximum periods and simulation of the ionospheric conditions before the scintillation onset. The results shows some patterns which may help to prevent several satellite-based technological applications suffering disruptions due to scintillation issues.
Lalit Mohan Joshi, Samireddipelle Sripathi, Muppidi Ravi Kumar, and Esfhan Alam Kherani
Ann. Geophys., 36, 25–35,Short summary
This work deals with the theoretical investigation of the inherent north&endash;south asymmetry in the ionospheric response to seismic infrasound. Magnetic field parallel component of the wind vector associated with the seismic infrasound varies significantly in the north–south direction due to the variation in the inclination of the Earth's magnetic field. This and other related aspects have been investigate using the physics-based ionospheric model.
Patricia Mara de Siqueira Negreti, Eurico Rodrigues de Paula, and Claudia Maria Nicoli Candido
Ann. Geophys., 35, 1309–1326,Short summary
The total electron content (TEC) is being extensively used to monitor the ionospheric behavior under geomagnetically quiet and disturbed conditions. The TEC presents significant changes during geomagnetic disturbed periods, causing degradation of signals in navigation systems and satellite communication. The geomagnetically disturbed periods occur due to enhanced solar activity and we show that the TEC presents intensifications not only during geomagnetic storms but also during HILDCAA events.
Marcio T. A. H. Muella, Marcelo H. Duarte-Silva, Alison O. Moraes, Eurico R. de Paula, Luiz F. C. de Rezende, Lucilla Alfonsi, and Bruno J. Affonso
Ann. Geophys., 35, 1201–1218,Short summary
In this study we analyzed ~ 17 years of GPS data from receivers installed in the observatory of Cachoeira Paulista, Brazil. We statistically analyzed the occurrence of GPS signal amplitude fluctuations caused by irregularities in the Earth's upper atmosphere. These signal fluctuations are known to provoke positional errors for GPS users. The results revealed that the secular variations in the Earth’s magnetic field are affecting the climatology of such GPS signal fluctuations.
Fabiano S. Rodrigues, Eurico R. de Paula, and Gebreab K. Zewdie
Ann. Geophys., 35, 393–402,Short summary
We present results of Capon's method for the estimation of in-beam images of equatorial spread F (ESF) irregularities observed by the São Luís radar interferometer. Results of numerical simulations show that, despite the short baselines of the system, the method is capable of distinguishing localized features with kilometric scale sizes (zonal direction). Results from the application of Capon’s method to actual measurements show that it is able to resolve features expected to occur in ESF.
J. M. Smith, F. S. Rodrigues, and E. R. de Paula
Ann. Geophys., 33, 1403–1412,
F. S. Rodrigues, E. B. Shume, E. R. de Paula, and M. Milla
Ann. Geophys., 31, 1867–1876,