@Article{SabaPintPintJrOd:2000:StBaMe,
               author = "Saba, Marcelo Magalhaes Fares and Pinto Junior, Osmar and Pinto, 
                         Iara Regina Cardoso de Almeida and Jr. Odim, Mendes",
                title = "Stratospheric balloon measurements of electric fields associated 
                         with thunderstorms and lightning in Brazil",
              journal = "Journal of Geophysical Research",
                 year = "2000",
               volume = "105",
               number = "D14",
                pages = "18091--18097",
             keywords = "GEOF{\'{\I}}SICA ESPACIAL, ionosfera, radia{\c{c}}{\~a}o, 
                         temporal, medi{\c{c}}{\~a}o, nuvens bigorna, condutividade, 
                         conductivity, storm, ionosphere, radiation, measurements, anvil 
                         clouds.",
             abstract = "Measurements of electric fields associated with thunderstorms and 
                         lightning were obtained during two balloon flights carrying 
                         double-probe electric field detectors launched from Cachoeira 
                         Paulista (22 degrees 44'S, 44 degrees 56'W), Brazil, on January 
                         26, 1994, and March 23, 1995. From data obtained in 1994, a linear 
                         relationship between the quasi-de vertical electric field peak 
                         amplitude and the decay time constant of lightning signatures was 
                         found for negative flashes. The results are compared to similar 
                         data for intracloud flashes. Based on electric field data obtained 
                         in 1995 and on the present knowledge about the differences between 
                         positive cloud-to-ground and intracloud flashes, two methods to 
                         distinguish them at balloon altitudes are presented: The first is 
                         based on an estimate of the destroyed charge in the event; the 
                         second is based on the peak amplitude ratio between the vertical 
                         quasi-de and the VLF electric field. The behavior of the vertical 
                         quasi-de electric field before and after large cloud-to-ground 
                         lightning flashes is discussed and attributed to the existence of 
                         a shielding layer around the thunderstorm. This shielding layer is 
                         associated with a threefold or greater decrease in the 
                         conductivity inside the cloud. An abrupt variation observed in the 
                         quasi-dc electric field possibly associated with the occurrence of 
                         positive flashes was observed and attributed to the formation of a 
                         transient shielding layer just above the thunderstorm, which could 
                         be produced by the near-breakdown field inside the cloud.",
                 issn = "0148-0227 and 2156-2202",
                label = "9432",
           targetfile = "2000_saba.pdf",
        urlaccessdate = "08 maio 2024"
}