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@ElectronicSource{KouadioMachServ::TrAtCy,
             abstract = "We investigate the possibility that hurricanes (H) spreading into 
                         the tropical Atlantic are originally connected with mesoscale 
                         convective systems (MCSs) previously generated on the West African 
                         continent. The analysis is carried out over 2004 and 2005, during 
                         which we find ten cases (six in 2004, four in 2005, all during 
                         July-August-September) for which such a connection can be made. 
                         For each one of the selected cases a backward methodology is 
                         performed using both subjective and objective analyses. This 
                         methodology is summarized as follows: starting from the date and 
                         position of the studied H when it is primarily catalogued as a 
                         tropical depression, we look backward at a possible easterly wave 
                         which may be the physical bond between the H initiation and an MCS 
                         dissipation in the ocean off the African coast. In this subjective 
                         step we use the wave signature from the 700 hPa vorticity at a 
                         6-hour frequency given by the reanalysis of the NCEP, as well as 
                         the MCS dataset provided by the MSG-7 images. Having associated 
                         the easterly wave with a sufficiently consequential MCS in terms 
                         of intensity and lifespan, we proceed, in a second step, to an 
                         objective backward analysis to go up to the time until the origin 
                         (date and position) of this MCS. In this second step we adapt a 
                         recent tracking methodology (FORTRACC) to individually track each 
                         MCS at a 30-minute frequency by using a dynamical threshold 
                         temperature. We find that practically all the selected cases (9 
                         out of 10) originate from a roughly limited area over West Africa. 
                         Mostly of MCS-H cases studied, shown an increase in the relative 
                         vorticity after MCS dissipation. As another important result, such 
                         connection between these MCSs which originate in West Africa and 
                         the occurrences of hurricanes takes place when a dipole in the sea 
                         surface temperature (SST) anomaly is observed between the Main 
                         Development Region (MDR) of the hurricanes (positive SST anomaly), 
                         and the equatorial tongue in the Gulf of Guinea (negative SST 
                         anomaly). .",
              address = "S{\~a}o Jos{\'e} dos Campos",
          affiliation = "University of Cocody, Abidjan, UFR-SSMT, Laboratory of Atmospheric 
                         Physics, 22 BP 582 Abidjan 22,C{\^o}ted’Ivoire. Visiting 
                         Scientist at Divis{\~a}o Sat{\'e}lite e Sistemas Ambiantes 
                         (CPTEC/INPE) and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE/CPTEC)} and Institut de Recherche pour le D{\'e}veloppement 
                         (IRD-UR182), Visiting Scientist at Funda{\c{c}}{\~a}o Cearense 
                         de Meteorologia e Recursos H{\'{\i}}dricos (FUNCEME)",
               author = "Kouadio, Yves K. and Machado, Luiz Augusto Toledo and Servain, 
                         Jacques",
             keywords = "hurricanes, mesoscale convective systems, tropical Atlantic, SST 
                         dipole.",
             language = "en",
       lastupdatedate = "2007-12-15",
            publisher = "Instituto and Nacional and de and Pesquisas and Espaciais",
                  ibi = "6qtX3pFwXQZGivnK2Y/SsgSq",
                  url = "http://urlib.net/rep/6qtX3pFwXQZGivnK2Y/SsgSq",
           targetfile = "v1.pdf",
                title = "Tropical Atlantic Cyclogenesis Coming from West African Mesoscale 
                         Convective Systems",
         typeofmedium = "On-line",
        urlaccessdate = "17 jan. 2021"
}


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