@Article{FontesMuelReseFagu:2024:EvAnSp,
               author = "Fontes, Pedro A. and Muella, M{\'a}rcio Tadeu A. H. and Resende, 
                         Laysa Cristina Araujo and Faguntes, P. R.",
          affiliation = "{Universidade do Vale do Para{\'{\i}}ba (UNIVAP)} and 
                         {Universidade do Vale do Para{\'{\i}}ba (UNIVAP)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Universidade do Vale 
                         do Para{\'{\i}}ba (UNIVAP)}",
                title = "Evidence of anti-correlation between sporadic (Es) layers 
                         occurrence and solar activity observed at low latitudes over the 
                         Brazilian sector",
              journal = "Advances in Space Research",
                 year = "2024",
               volume = "73",
               number = "7",
                pages = "3563--3577",
                month = "Apr.",
             keywords = "Ionosphere, Solar activity, Sporadic (Es) layer.",
             abstract = "Sporadic E-layers (Es) are thin and denser layers with high 
                         ionization observed at about 100140 km altitude in the E region. 
                         Their formation is mainly associated with the tidal components of 
                         the diurnal and semidiurnal winds with the convergence of ions 
                         driven by the wind shear mechanism. This present work shows 
                         evidence of the relationship between the occurrence of Es layers 
                         and the solar activity at two observatories located in the 
                         Brazilian sector, the near-equatorial site of Palmas (PAL, 10.17° 
                         S; 48.33° W; dip lat. \−7.31°) and the low latitude station 
                         of S{\~a}o Jos{\'e} dos Campos (SJC, 23.18° S; 45.89° W; dip 
                         lat. \−19.35°). The analysis was performed from 
                         December/2008 to November/2009 (a period of low solar activity) 
                         and from December/2013 to November/2014 (a period of high solar 
                         activity) using data collected from two digital ionosondes. Our 
                         results show an anti-correlation of the Es layer occurrence 
                         concerning the solar activity over both stations studied here. A 
                         more clearly observed anti-correlation at the SJC station can be 
                         attributed to a greater tidal amplitude at low latitudes. Other 
                         relevant aspects of the observations associated with the formation 
                         of the Es layers are highlighted and discussed.",
                  doi = "10.1016/j.asr.2023.09.040",
                  url = "http://dx.doi.org/10.1016/j.asr.2023.09.040",
                 issn = "0273-1177 and 1879-1948",
             language = "en",
           targetfile = "1-s2.0-S0273117723007627-main.pdf",
        urlaccessdate = "16 jun. 2024"
}