@Article{LatinovicChaRanMedLyr:2019:SeClOn,
               author = "Latinovic, Dragan and Chan, Chou Sin and Rancic, Miodrag and 
                         Medeiros, Gustavo Sueiro and Lyra, Andr{\'e} de Arruda",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {MSG at EMC/NCEP/NOAA} 
                         and {Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)}",
                title = "Seasonal climate and the onset of the rainy season in 
                         western-central Brazil simulated by Global Eta Framework model",
              journal = "International Journal of Climatology",
                 year = "2019",
               volume = "39",
               number = "3",
                pages = "1429--1445",
                month = "mar.",
             keywords = "GEF, Eta model, monsoon onset, rainy season, South America.",
             abstract = "The seasonal cycle of precipitation in tropical South America is 
                         determined by the monsoonal system. The transition from dry to wet 
                         season occurs in austral spring (September-November, SON) when 
                         intense convection from northwestern South America rapidly shifts 
                         southwards to the southern Amazon Basin and western-central Brazil 
                         (WCB) in October and further to the southeast of Brazil in 
                         November. This study evaluates ability of the global atmospheric 
                         model, Global Eta Framework (GEF), at 25-km horizontal resolution, 
                         to simulate the onset of the rainy season in WCB region. The 
                         simulations are based on a five-member ensemble seasonal 
                         integrations for the years 2011 and 2013. Evaluation of mean 
                         global simulated fields, such as 200-hPa wind, 500-hPa 
                         geopotential height, 850-hPa temperature and wind, and MSLP at the 
                         surface, for the SON period indicates high level of agreement with 
                         reanalyses and observations, both in spatial distribution and 
                         intensity for most of the variables. The variable of the lowest 
                         skill is precipitation, which is overestimated over some tropical 
                         oceanic regions and underestimated over tropical continental 
                         regions, including South America. The onset of the rainy season is 
                         determined using methods based on precipitation and outgoing 
                         long-wave radiation (OLR). The threshold based on simulated 
                         precipitation is also calculated as an alternative method for 
                         defining monsoon onset. Comparison of the 5-day averaged values 
                         (pentads) of precipitation and OLR of all members of the ensemble 
                         and the ensemble mean against the observed data shows the ability 
                         of GEF to reproduce the typical pattern of transition from dry to 
                         wet season in WCB, although most of ensemble members tend to 
                         underestimate precipitation and overestimate OLR. The onset date 
                         is delayed for few pentads in the model simulations.",
                  doi = "10.1002/joc.5892",
                  url = "http://dx.doi.org/10.1002/joc.5892",
                 issn = "0899-8418",
             language = "en",
           targetfile = "Latinovi-_et_al-2019-International_Journal_of_Climatology.pdf",
        urlaccessdate = "26 abr. 2024"
}