author = "Smith, J. M. and Rodrigues, F. S. and Paula, Eurico Rodrigues de",
          affiliation = "{University of Texas at Dallas} and {University of Texas at 
                         Dallas} and {Instituto Nacional de Pesquisas Espaciais (INPE)}",
                title = "Radar and satellite investigations of equatorial evening vertical 
                         drifts and spread F",
              journal = "Annales Geophysicae",
                 year = "2015",
               volume = "33",
                pages = "1403--1412",
             keywords = "Ionosphere (electric fields and currents, equatorial ionosphere, 
                         ionospheric irregularities).",
             abstract = "We analyzed pre-midnight equatorial F region observations made by 
                         the 30 MHz coherent backscatter radar of S{\~a}o Luis, Brazil 
                         between August 2010 and February 2012. These measurements were 
                         processed, and used to create monthly maps of the echo occurrence 
                         as a function of local time and height. The maps show the 
                         inter-annual variability associated with equatorial spread F (ESF) 
                         occurrence in the Brazilian longitude sector. We also constructed 
                         monthly curves of the evening vertical drifts, for the Brazilian 
                         sector, using measurements by the ion velocity meter (IVM) onboard 
                         the C/NOFS satellite. The IVM evening drifts show a good overall 
                         agreement with the Scherliess and Fejer (1999) empirical model. 
                         Measured and model drifts show the development of the pre-reversal 
                         enhancement (PRE) of the vertical plasma drifts during ESF season. 
                         Using joint radar and satellite measurements, we found that 
                         evening (18:0018:30 LT) mean non-negative drifts provide a 
                         necessary but not sufficient condition for the occurrence of 
                         topside ESF echoes. Evening downward (negative) drifts preceded 
                         the absence of topside ESF irregularities.",
                  doi = "10.5194/angeo-33-1403-2015",
                  url = "http://dx.doi.org/10.5194/angeo-33-1403-2015",
                 issn = "0992-7689",
             language = "en",
           targetfile = "2015_smith.pdf",
        urlaccessdate = "24 jan. 2021"