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@Article{RibeiroBosa:2018:ElMiLa,
               author = "Ribeiro, Bruno Zanetti and Bosart, L. F.",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {University 
                         at Albany}",
                title = "Elevated mixed layers and associated severe thunderstorm 
                         environments in South and North America",
              journal = "Monthly Weather Review",
                 year = "2018",
               volume = "146",
               number = "1",
                pages = "3--28",
                month = "jan.",
             keywords = "Orographic effects, Reanalysis data, Severe storms, Synoptic 
                         climatology.",
             abstract = "This study presents a climatological and composite analysis of 
                         elevated mixed layers (EMLs) in South and North America derived 
                         from the NCEP Climate Forecast System Reanalysis. The EMLs are 
                         identified based on objective criteria applied to the reanalysis 
                         data. Composite analyses of synoptic-scale conditions and severe 
                         weather parameters associated with spring EML cases are presented. 
                         EMLs are more frequent immediately to the east of the Andes and 
                         the Rockies. The North American EMLs form by surface heating over 
                         the higher terrain of the Rockies, with peak frequency occurring 
                         in spring and summer. EMLs in South America are generated by 
                         differential temperature advection due to ageostrophic 
                         circulations east of the Andes, as indicated by the temperature 
                         lapse rate tendency equation, which relates to the higher 
                         frequency of EMLs during the cold season in South America. EMLs 
                         over North America are about 100 hPa lower than over South America 
                         due to the lower height of the Rockies in comparison to the Andes. 
                         The synoptic conditions associated with EMLs in South and North 
                         America are characterized by an upper-level trough upstream and 
                         low-level moisture flux convergence due to poleward-directed flow, 
                         favoring synoptic-scale ascent poleward of the EML location, where 
                         the convective inhibition is relatively low. When EMLs occur, 
                         higher surface-based convective available potential energy and 
                         low-level storm-relative helicity, in association with lower 
                         lifting condensation level heights observed in North America, 
                         indicate that surface-based supercell storms and tornadoes are 
                         more likely to occur on this continent in comparison with South 
                         America, corroborating observations.",
                  doi = "10.1175/MWR-D-17-0121.1",
                  url = "http://dx.doi.org/10.1175/MWR-D-17-0121.1",
                 issn = "0027-0644",
             language = "en",
        urlaccessdate = "28 nov. 2020"
}


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