@Article{SchumannSabaSilvSchu:2013:ElFiCh,
               author = "Schumann, Carina and Saba, Marcelo Magalh{\~a}es Fares and Silva, 
                         Raphael Bueno Guedes da and Schulz, Wolfgang",
          affiliation = "INPE, BR-12201970 Sao Jose Dos Campos, SP, Brazil. and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and INPE, BR-12201970 Sao 
                         Jose Dos Campos, SP, Brazil. and OVE ALDIS, A-1190 Vienna, 
                         Austria.",
                title = "Electric fields changes produced by positives cloud-to-ground 
                         lightning flashes",
              journal = "Journal of Atmospheric and Solar-Terrestrial Physics",
                 year = "2013",
               volume = "92",
               number = "6",
                pages = "37--42",
                month = "Jan.",
             keywords = "positive lightning, preliminary breakdown, return stroke, electric 
                         field.",
             abstract = "Positive flashes correspond to approximately only 10\\% of the 
                         total number of flashes produced by a thunderstorm. However, 
                         strokes with high peak currents and long continuing currents are 
                         usually present in positive flashes. Therefore, positive flashes 
                         are responsible for more intense damage than the negative ones. 
                         Positive flashes often are preceded by significant and long 
                         duration intracloud (IC) discharge activity. We observe in detail 
                         the electric field variations produced by 80 cloud-to-ground 
                         lightning flashes in 9 different storms in S. Paulo, Brazil during 
                         the summers of 2009-2011. Intracloud discharges preceding the 
                         positive cloud-to-ground flashes and some characteristics of the 
                         electric field changes produced by the return stroke that occurred 
                         at ranges of 3-80 km from the site of the electric field 
                         measurements were analyzed. All flashes presented breakdown pulses 
                         prior to the return stroke. The mean time interval between the 
                         preliminary breakdown pulse (PBP) and return stroke was 157 ms. 
                         The pulse train duration have a mean value of 3.1 ms. Only 6 out 
                         of 80 cases analyzed did not present pulse trains but only one 
                         single bipolar breakdown pulse before the return stroke. In 
                         95\\% of cases the initial breakdown pulse presented the same 
                         initial polarity of the succeeding return stroke. Time interval 
                         between pulses in a pulse train had a mean value of 280 mu s. The 
                         mean values of pulse width is 25.2 mu s. The mean values of 
                         zero-to-peak risetimes and of the 10-90\\% risetimes for 72 
                         return strokes electric field waveforms are 9.5 and 5.7 mu s 
                         respectively. The AM value of peak amplitudes of the positive 
                         return strokes fields normalized to 100 km is 17.0 V/m. (C) 2012 
                         Elsevier Ltd. All rights reserved.",
                  doi = "10.1016/j.jastp.2012.09.008",
                  url = "http://dx.doi.org/10.1016/j.jastp.2012.09.008",
                 issn = "1364-6826",
                label = "isi",
             language = "en",
           targetfile = "1-s2.0-S1364682612002295-main.pdf",
        urlaccessdate = "16 jun. 2024"
}