Relationship between daily atmospheric circulation patterns and South Atlantic Convergence Zone (SACZ) events

This study presents the daily atmospheric circulation patterns at surface and altitude related to the South Atlantic Convergence Zone (SACZ) events that occurred between 2007 and 2017. For this analysis, Principal Pattern Sequence Analysis (PPSA) and sea level pressure and geopotential height reanal...

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Detalles Bibliográficos
Autores: Escobar, Gustavo Carlos Juan, Reboita, Michelle Simões
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:México
Institución:UNIVERSIDAD NACIONAL AUTÓNOMA DE MÉXICO
Repositorio:Atmósfera
Idioma:inglés
OAI Identifier:oai:ojs.pkp.sfu.ca:article/52936
Acceso en línea:https://www.revistascca.unam.mx/atm/index.php/atm/article/view/52936
Access Level:acceso abierto
Palabra clave:synoptic variability
classification
SACZ
Descripción
Sumario:This study presents the daily atmospheric circulation patterns at surface and altitude related to the South Atlantic Convergence Zone (SACZ) events that occurred between 2007 and 2017. For this analysis, Principal Pattern Sequence Analysis (PPSA) and sea level pressure and geopotential height reanalysis were used. Four typical atmospheric circulation patterns associated with SACZ episodes were identified. Three of them are related to the propagation of a cold front toward southeastern Brazil with a post-frontal anticyclone moving over the Atlantic Ocean. The fourth pattern is associated with the presence of a cut-off low centered over the central-south region of Brazil that induces moisture transport from the Atlantic Ocean and from the Amazon basin to most of southeastern Brazil. Considering the first three patterns, they represent, respectively, a frontal wave, a classical cold front, and a slow-moving cold front. All of these patterns provide permanent northwesterly winds in the lower troposphere over southeastern Brazil from two days before the SACZ occurrence.