@Article{SantosAbdSouBatSob:2017:UnBeQu,
               author = "Santos, {\^A}ngela Machado dos and Abdu, Mangalathayil Ali and 
                         Souza, Jonas Rodrigues de and Batista, Inez Staciarini and Sobral, 
                         Jos{\'e} Humberto Andrade",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE)}",
                title = "Unusual behavior of quiet-time zonal and vertical plasma drift 
                         velocities over Jicamarca during the recent extended solar minimum 
                         of 2008",
              journal = "Annales Geophysicae",
                 year = "2017",
               volume = "35",
                pages = "1219--1229",
             keywords = "Ionosphere (equatorial ionosphere).",
             abstract = "The influence of the recent deep and prolonged solar minimum on 
                         the daytime zonal and vertical plasma drift velocities during 
                         quiet time is investigated in this work. Analyzing the data 
                         obtained from incoherent scatter radar from Jicamarca 
                         (11.95\◦ S, 76.87\◦ W) we observe an anomalous 
                         behavior of the zonal plasma drift during June 2008 characterized 
                         by lower than usual daytime westward drift and its early afternoon 
                         reversal to eastward. As a case study the zonal drift observed on 
                         24 June 2008 is modeled using a realistic low-latitude ionosphere 
                         simulated by the Sheffield University Plasmasphere-Ionosphere 
                         Model-INPE (SUPIMINPE). The results show that an anomalously low 
                         zonal wind was mainly responsible for the observed anomalous 
                         behavior in the zonal drift. A comparative study of the vertical 
                         plasma drifts obtained from magnetometer data for some periods of 
                         maximum (20002002) and minimum solar activity (1998, 2008, 2010) 
                         phases reveal a considerable decrease on the E-region conductivity 
                         and the dynamo electric field during 2008. However, we believe 
                         that the contribution of these characteristics to the unusual 
                         behavior of the zonal plasma drift is significantly smaller than 
                         that arising from the anomalously low zonal wind. The SUPIM-INPE 
                         result of the critical frequency of the F layer (foF2) over 
                         Jicamarca suggested a lower radiation flux than that predicted by 
                         solar irradiance model (SOLAR2000) for June 2008.",
                  doi = "10.5194/angeo-35-1219-2017",
                  url = "http://dx.doi.org/10.5194/angeo-35-1219-2017",
                 issn = "0992-7689",
             language = "en",
           targetfile = "santos_unusual.pdf",
        urlaccessdate = "18 abr. 2024"
}