@InProceedings{MarengoSoarSaul:2002:ClLoJe,
               author = "Marengo, Jos{\'e} Antonio and Soares, Wagner Rodrigues and Saulo, 
                         Celeste",
          affiliation = "Instituto Nacional de Pesquisas Espaciais, Centro de Previs{\~a}o 
                         do Tempo e Estudos Clim{\'a}ticos (INPE.CPTEC) and Instituto 
                         Nacional de Pesquisas Espaciais, Centro de Previs{\~a}o do Tempo 
                         e Estudos Clim{\'a}ticos (INPE.CPTEC) and CIMA/UBA",
                title = "Climatology of Low-Level Jet East of the Andes as derived from the 
                         NCEP reanalyses",
            booktitle = "Anais...",
                 year = "2002",
                pages = "885--891",
         organization = "Congresso Brasileiro de Meteorologia, 12.",
             keywords = "METEOROLOGY, Climatology, Low-level jet, Andes mountains (South 
                         America), METEOROLOGIA, Climatologia, Jato de baixo 
                         n{\'{\i}}vel, Montanhas dos Andes (Am{\'e}rica do Sul).",
             abstract = "A climatology of the Low Level Jet East of the Andes (LLJ)is 
                         developed using the 1950-2000 circulation and moisture fields from 
                         the NCEP reanalyses. Upper and low-level circulation fields were 
                         determined for mean summer and wintertime, and for composites of 
                         LLJ events during those seasons. The Bonner criterion 1 was 
                         applied for circulation fields for sites en central Bolivia 
                         (assumed as the core region), and in northern Paraguay (exit 
                         region)to determine the spatial and temporal characteristics of 
                         the LLJ. On the circulation characteristics, composites of 
                         summertime LLJs shows the enhanced meridional moisture transport 
                         coming from tropical South America. The upper level circulation 
                         shows a wave train emanating from the West Pacific propagating 
                         towards South America. The intensification of the LLJ obeys to the 
                         establishment of an upper-level ridge over southern Brazil and a 
                         trough over most of Argentina. Regarding the time variability, LLJ 
                         seems to occur all year long, with the LLJ bringing tropical air 
                         masses from the Amazon into southern Brazil-Northern Argentina 
                         more frequent in summer, and the LLJ that brings subtropical air 
                         from the Subtropical Atlantic High more frequent during winter. 
                         The diurnal cycle shows that LLJs are more frequent and intense 
                         between 06 and 12 (01 and 07 LST)for the warm season in the core 
                         region of the jet, while at the exit region the maximum is 
                         detected between 00 and 06 Z. during the cold season. This is 
                         somewhat similar to the summertime LLJs in the US Great Plains. At 
                         interannual time scales, even though there is a weak tendency for 
                         stronger/more frequent LLJ episodes during El Ni¤o year 1998, we 
                         cannot affirm with large degree of certainty that there is any 
                         relationship between the occurrence of El Niņo events and the 
                         number and/or intensity of LLJ episodes.",
  conference-location = "Foz do Igua{\c{c}}u",
      conference-year = "4-9 ago.",
           copyholder = "SID/SCD",
             language = "pt",
         organisation = "SBMET",
           targetfile = "Marengo_Climatology LLJ .pdf",
               volume = "1",
        urlaccessdate = "23 abr. 2024"
}