author = "Andrade, Kelen Martins and Cavalcanti, Iracema Fonseca de 
          affiliation = "{Centro Nacional de Monitoramento e Alertas de Desastres Naturais 
                         (CEMADEN)} and {Instituto Nacional de Pesquisas Espaciais 
                title = "Atmospheric characteristics that induce extreme precipitation in 
                         frontal systems over Southeastern Brazil during summer: 
                         Observations and atmospheric model simulation",
              journal = "International Journal of Climatology",
                 year = "2018",
               volume = "38",
               number = "14",
                pages = "5368--5385",
                month = "Nov.",
             keywords = "AGCM, atmospheric anomalies, cold fronts, precipitation extremes, 
                         South America.",
             abstract = "Cold fronts are the most frequent synoptic systems that affect 
                         Southeast Brazil during the whole year. The highest frequency of 
                         these systems at these latitudes occurs in the months of spring 
                         (SON) and winter (JJA), but the highest associated precipitation 
                         occurs in the spring (SON) and summer (DJF). Some of these fronts 
                         present light rains but others cause heavy precipitation, giving 
                         rise to flooding and landslides, mainly in the summer. Composites 
                         of the two cases (light and heavy rainfall) are analysed for the 
                         summer season. Large-scale and regional features are shown to 
                         discuss the differences in precipitation. Regional differences are 
                         seen in the position and intensity of low pressure and postfrontal 
                         high. The differences are also associated with the humidity flux 
                         and convergence over the region. The main difference at high 
                         levels is the position of the frontal trough, which is close to 
                         the region in the wet cases and displaced to the ocean in the dry 
                         cases. Features of the Southern Annular Mode and Madden-Julian 
                         Oscillation show opposite patterns in the two cases. These modes 
                         of variability can modulate extra-tropical wave trains over the 
                         Pacific, which have different behaviour downstream, over South 
                         America and South Atlantic Ocean. The eddy kinetic energy is 
                         stronger over Southeastern Pacific and Southern South America, and 
                         wave activity shows energy propagation towards the continent in 
                         the wet cases. Similar analyses with results of a global 
                         atmospheric model show that the general atmospheric 
                         characteristics of a frontal system are reproduced, as the 
                         temperature gradient, the wind confluence and the ridge-trough 
                         pair associated with the frontal system. The model represents the 
                         differences with respect to moisture flux and the frontal trough 
                         position, but underestimates the moisture convergence, eddy 
                         kinetic energy and wave activity, in the wet cases.",
                  doi = "10.1002/joc.5744",
                  url = "http://dx.doi.org/10.1002/joc.5744",
                 issn = "0899-8418",
             language = "en",
           targetfile = "andrade_atmospheric.pdf",
        urlaccessdate = "22 jan. 2021"