@Article{BatistaCSTTGBBM:2002:SiLiOb,
               author = "Batista, Paulo Prado and Clemesha, Barclay Robert and Simonich, 
                         Dale Martin and Taylorb, Michael J. and Takahashi, Hisao and 
                         Gobbi, Delano and Batista, Inez Staciarini and Buriti, Ricardo A. 
                         and Medeiros, Amauri Fragoso de",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)}",
                title = "Simultaneous lidar observation of a sporadic sodium layer, a 
                         {"}wall{"} event in the OH and OI5577 airglow images and the 
                         meteor",
              journal = "Journal of Atmospheric and Solar-Terrestrial Physics",
                 year = "2002",
               volume = "64",
               number = "12-14",
                pages = "1327--1335",
                month = "Aug.-Sep.",
             keywords = "AERONOMIA, aeroluminesc{\^e}ncia, imagens, radar {\'o}ptico, 
                         aeroluminesc{\^e}ncia naturna, airglow, images, optical radar 
                         (Lidar), nughtglow.",
             abstract = "Rare and sporadic events, caused by unusual conditions in the MLT 
                         region may occur such as the sporadic metal layers, observed by 
                         lidars, and the more recently detected sharp front in the 
                         nightglow emissions imaged with CCD all sky cameras. Few events of 
                         this latter kind have been reported in the literature and no 
                         simultaneous occurrence of both. In this work, we report the 
                         observation of a sporadic sodium layer measured by lidar in 
                         S{\~a}o Jos{\'e} dos Campos, Brazil (22.5øS, 46øW)on the night 
                         of July 13-14, 1999 which was followed by a rare {"}wall{"} event 
                         observed at Cachoeira Paulista (CP)(23øS, 45øW)in the OH NIR and 
                         OI5577 by a CCD imager, and zenith tilting filter photometers. The 
                         wind field was also observed by a SkiYmet meteor radar system also 
                         operated at CP. At around 23:45 the sodium layer had an abrupt 
                         change in its shape. At the same time unusual situation also had 
                         occurred in the airglow data taken in CP both with the imager and 
                         with the zenith photometer. A sequence of all sky images for the 
                         OI557.7 nm and OH NIR showed very clear lines dividing the sky 
                         into bright and dark areas, with the first propagating from the NE 
                         to SW at 70 m/s and the second propagating to NNE. Zenith 
                         photometer also showed a rapid decrease of the OH(6,2)intensity at 
                         around 23:45 and a very large increase in the rotational 
                         temperature of O2(0,1)(at 94 km)from 23:00 to 24:00 (40 K). The 
                         meridional and zonal wind structure measured by the meteorradar in 
                         CP showed that from 21:00 to 01:00 a wind shear was present both 
                         in the meridional and zonal winds with the phase propagating from 
                         97 to 80 km during this time which were very well correlated with 
                         the vertical displacement of the sporadic peak. Large-amplitude 
                         gravity wave was also detected. The temperature enhancement above 
                         90 km could be responsible for the sodium density increase and 
                         also for the set up of the conditions for the airglow events.",
           copyholder = "SID/SCD",
                 issn = "1364-6826",
                label = "9882",
           targetfile = "Simultaneous lidar observation of a sporadic sodium layer.pdf",
        urlaccessdate = "01 maio 2024"
}