@InProceedings{MoroXDRSLLYWS:2021:StIoVa,
               author = "Moro, Juliano and Xu, J. and Denardini, Clezio Marcos and Resende, 
                         Laysa Cristina Ara{\'u}jo and Silva, R{\'e}gia Pereira da and 
                         Liu, Z. and Li, H. and Yan, C. and Wang, C. and Schuch, Nelson 
                         Jorge",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {State Key 
                         Laboratory of Space Weather} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE)} and {Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {State Key Laboratory of Space Weather} and {State Key Laboratory 
                         of Space Weather} and {State Key Laboratory of Space Weather} and 
                         {State Key Laboratory of Space Weather} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)}",
                title = "Study of the ionospheric variability in the South American 
                         Magnetic Anomaly (SAMA) during solar minimum (2017-2018)",
                 year = "2021",
         organization = "Simp{\'o}sio Brasileiro de Geof{\'{\i}}sica Espacial e 
                         Aeronomia, 8. (SBGEA)",
             abstract = "We investigate for the first time the variability of the F2 layer 
                         critical frequency (foF2), its peak height (hmF2), the thickness 
                         parameter B0, and the E-region critical frequency (foE) over Santa 
                         Maria (29.7oS, 53.7oW, dip= - 38o), a station located in the 
                         central region of the South American Magnetic Anomaly (SAMA). The 
                         selected ionospheric parameters were obtained from ionograms 
                         recorded by a recent Digisonde Portable Sounder (DPS-4D). The time 
                         period covers 309 days from 1st September 2017 to 30th August 
                         2018. The diurnal analyses revealed a large day-to-day ionospheric 
                         variability, with some peculiarities as a strong semi-annual 
                         pattern superimposed to expected ionospheric behavior. 
                         Furthermore, the results show significant differences between the 
                         averaged foF2 in December and June solstices, revealing a possible 
                         presence of the annual asymmetry. The coefficient of variation 
                         (CV) is used as a quantitative description of the variability of 
                         each parameter versus time and season. Considering low solar flux 
                         and geomagnetically quiet days only, we note that CV is smaller 
                         during the daytime, and larger during nighttime for all 
                         parameters. The least variable ionospheric parameter in our study 
                         is foE, while the most variable one is B0. Regarding the F2- layer 
                         parameters, we observe that foF2 is much more variable than hmF2. 
                         We attribute the observed CV to the neutral atmosphere source over 
                         Santa Maria. The ionospheric variability is in general enhanced 
                         during geomagnetically disturbed periods. The estimated CV is 
                         higher over Santa Maria than Wuhan (30.5oN, 114.4oE, dip= 46o), 
                         China, a station with no influence of the SAMA.",
  conference-location = "Online",
      conference-year = "22-26 mar.",
             language = "en",
           targetfile = "Moro et al. (2020) VIII SBGEA final.pdf",
        urlaccessdate = "09 maio 2024"
}