Winds and precipitation are two meteorological variables of great impact on the economy and society, especially when extreme events occur. The objective of this study is to investigate the subtropical cyclone (SC) impacts on near‐surface wind extremes (defined by 95th percentile) and precipitation in the South Atlantic basin. For the period 1979–2015, the analysis used two reanalysis data (ERA5 and Climate Forecast System Reanalysis [CFSR]) and estimated precipitation from the Tropical Rainfall Measuring Mission (TRMM) considering the extended warm (from September to February) and cold (from March to August) seasons. A total of 169 SCs occurred in the warm season against 87 in the cold one. Two approaches are used to quantify SC impacts: Lagrangian, where the composites follow the cyclone center, and Eulerian, which considers the averaged environment during the cyclone lifecycle. In general, both approaches indicate SC contribution to the positive anomalies of mean and extreme near‐surface wind speeds to the east and northeast of a cyclogenetic region in southeastern Brazil (RG1). For all analyses conducted, wind speeds from CFSR are higher than in ERA5. The SC activity contributes to the enhancement of precipitation to the east and inside RG1 in an organized northwest‐southeast positive anomaly band from the continent to the ocean, while favoring drier conditions to the south. These positive precipitation anomalies are associated with an anomalous low pressure, low‐level moisture flux convergence and warm advection occurring at the same time with an upper‐level divergent flow near RG1. All these features are intensified in the cold season.
<p>New evaluation simulations with the ERA5 boundary conditions have been completed with the new model RegCM5 for all CORDEX-CORE domains at 25 km resolution. Model performances are satisfactory for all evaluation metrics for both the mean climate and extreme climate and for temperature, precipitation and cloud variables. For some of the domains the new model is able to remove some well know biases like the dry bias in the Amazon region in the CAM domain or the warm bias in the La Plata basin for the SAM domain. In other domains the RegCM5 performs consistently with the previous model version.&#160; One simulation at convection permitting resolution (CP) has been completed for the first time for the whole Euro-CORDEX domain thanks to the new semi implicit dynamical core implemented in the RegCM5 that allow the model to remain stable at such resolution even with time steps of 30 seconds at 3 km resolution.&#160; &#160;The evaluation of the CP simulation is comparable with the previous model evaluation over the ALPS domain with a tendency to improve both the dry and wet bias in summer and winter respectively. Over the whole Euro-CORDEX domain validation of the sub daily statistic for the precipitation frequency, intensity and diurnal cycle confirm the fitness for purposes of this new model version to run at such resolution for such extended region. A further CP configuration is also tested with two overlapping longitudinal stripe domains covering the Euro-CORDEX domain and the comparison is shown between the two CP simulations.&#160;</p>
O Grupo de Estudos Climáticos da Universidade de São Paulo (GrEC-USP) foi criado em 1997 por alunos de graduação e pós-graduação de Ciências Atmosféricas com o intuito de realizar discussões mensais sobre o clima e sua variabilidade, com foco especial sobre o Brasil, colocando uma síntese dessas discussões em forma de relatórios mensais. Com passar dos anos o Grupo manteve suas discussões mensais e elaboração dos relatórios que passaram a ser disponibilizados a comunidade acadêmica e ao público em geral. Além dos relatórios, o grupo também passou a disponibilizar produtos para o monitoramento e previsão do clima, além de promover atividades de extensão e divulgação científica a serviço da sociedade. Este trabalho apresenta a evolução do Grupo ao longo dos anos, bem como toda sua produção científica, com o objetivo de divulgar suas atividades e homenagear todos os alunos e pesquisadores que participaram dos 25 anos de história GrEC-USP.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.