Influence of sudden stratospheric warming on Brazil’s rainfall in the years 1988, 2002 and 2019

Sudden stratospheric warming (SSW) is a common event in the Northern Hemisphere but very rare in the Southern Hemisphere (SH), where its occurrence was documented in 1988, 2002, and 2019 on the Antarctic continent. Such events can arise when large amplitude planetary waves propagate from the troposp...

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Detalhes bibliográficos
Autores: Dalcol, Denise da Silva, Boiaski, Nathalie Tissot, Pinheiro, Damaris Kirsch
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:Brasil
Recursos:Universidade Federal de Santa Maria (UFSM)
Repositorio:Revista Ciência e Natura (Online)
Idioma:portugués
OAI Identifier:oai:ojs.pkp.sfu.ca:article/87951
Acesso em linha:https://periodicos.ufsm.br/cienciaenatura/article/view/87951
Access Level:acceso abierto
Palavra-chave:Sudden stratospheric warming
Polar vortex
Climate anomalies
Aquecimento abrupto da estratosfera
Vórtice polar
Anomalias climáticas
Descrição
Resumo:Sudden stratospheric warming (SSW) is a common event in the Northern Hemisphere but very rare in the Southern Hemisphere (SH), where its occurrence was documented in 1988, 2002, and 2019 on the Antarctic continent. Such events can arise when large amplitude planetary waves propagate from the troposphere to the stratosphere, disturbing the polar vortex and causing stratospheric warming within days. The weakening of the polar vortex impacts tropospheric circulation, forcing the Southern (or Northern) Annular Mode to remain negative for longer periods and resulting in climatic anomalies across the hemisphere. During SSW events in Antarctica, climatic anomalies were recorded in the SH. In eastern Australia, during the 2019 SSW, hotter and drier conditions were observed, resulting in wildfires. This study analyzed the spatiotemporal variability of precipitation in Brazil during three SSW events in Antarctica in 1988, 2002, and 2019, using precipitation data from the Brazilian Daily Weather Gridded Data (BR-DWGD) from 1961 to 2020. During these SSW events in Antarctica, the Southern Annular Mode remained negative. This weakening of the Antarctic polar vortex is reflected in anomalous patterns in precipitation maps, highlighting a potential connection between SSW events and climate changes in Brazil.