author = "Figueiredo, Cosme Alexandre Oliveira Barros and Takahashi, Hisao 
                         and Wrasse, Cristiano Max and Otsuka, Y. and Shiokawa, K. and 
                         Barros, Diego",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and ISEE, Nagoya University, Japan and 
                         ISEE, Nagoya University, Japan and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)}",
                title = "Medium-scale traveling ionospheric disturbances observed by 
                         detrended total electron content maps over Brazil",
              journal = "Journal of Geophysical Research: Space Physics",
                 year = "2018",
               volume = "123",
               number = "3",
                pages = "2215--2227",
                month = "Mar.",
             keywords = "gravity waves, ionosphere, TEC, TIDs, MSTIDs, GPS.",
             abstract = "A ground-based network of Global Navigation Satellite Systems 
                         receivers has been used to monitor medium-scale traveling 
                         ionospheric disturbances (MSTIDs). MSTIDs were studied using total 
                         electron content perturbation maps and keograms over 
                         south-southeast of Brazil during the period from December 2012 to 
                         February 2016. In total, 826 MSTIDs were observed mainly in 
                         daytime, thus presenting median values of horizontal wavelength, 
                         period, and horizontal phase velocity of 452 +/- 107 km, 24 +/- 4 
                         min. and 323 +/- 81 m/s, respectively. The direction of 
                         propagation varies on the season: during the winter (June-August), 
                         the waves preferentially propagated to north-northeast, while in 
                         the other seasons the waves propagated to other directions. The 
                         anisotropy observed in the MSTID propagation direction could be 
                         associated with the region of the gravity wave generation that 
                         takes place in the troposphere. We also found that the MSTIDs were 
                         observed most frequently during the daytime, between 11 and 15 
                         local time in winter and near to dusk solar terminator (17-19 
                         local time) in the other seasons. Furthermore, the occurrence of 
                         MSTIDs was higher in winter. We suggest that atmospheric gravity 
                         waves in the thermosphere, mesosphere, and troposphere could play 
                         an important role in generating the MSTIDs and the propagation 
                         direction may depend on location of the wave sources.",
                  doi = "10.1002/2017JA025021",
                  url = "http://dx.doi.org/10.1002/2017JA025021",
                 issn = "2169-9402",
             language = "en",
           targetfile = "Figueiredo_medium.pdf",
        urlaccessdate = "29 nov. 2020"