Atmospheric blockings in Coupled Model Intercomparison Project Phase 5 models with different representations of Antarctic sea ice extent

Autor(es)

CAMILA B. CARPENEDO ^[1] ; TÉRCIO AMBRIZZI ^[2]

Afiliação do(s) autor(es)

^[1] Universidade Federal do Paraná. Setor de Ciências Agrárias - Brasil

^[2] Universidade de São Paulo. Instituto de Astronomia - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Anais da Academia Brasileira de Ciências; v. 94, 2022-05-30.

Resumo

Abstract This study investigated whether there are differences in the frequency and position of Southern Hemisphere atmospheric blockings between Coupled Model Intercomparison Project Phase 5 models with different representations of Antarctic sea ice extent in historical experiments. In the model with the greatest sea ice underestimation (Model for Interdisciplinary Research on Climate version 5) there is a weakening of the polar jet and an increase in 500-hPa height. These atmospheric conditions favor the predomination of simulated blocking frequency overestimations (autumn-winter), in relation to the observed (ERA-Interim). On the other hand, in the models with the greatest sea ice overestimations (Community Climate System Model version 4) and the better sea ice representation (Norwegian Earth System Model version 1) there is a strengthening of the polar jet and weaker positive differences in 500-hPa height in the Antarctic region. These atmospheric conditions favor a predominance of simulated blocking frequency underestimations (all seasons). All models present a good representation of the preferred blocking regions (South Pacific), although they do not represent the longitudinal location of the maximum frequency. In years of sea ice retraction (expansion), there is a predominance of a higher (lower) blocking frequency in the 60°S for all models and observed data. (AU)

• Processo FAPESP: 12/17370-2 - Bloqueios atmosféricos associados à variabilidade extrema do gelo marinho antártico e impactos na América do Sul
• Beneficiário: Camila Bertoletti Carpenedo
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 17/09659-6 - Variabilidade interanual dos transportes meridionais através da rede transatlântica SAMOC (SAMBAR)
• Beneficiário: Edmo José Dias Campos
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 14/50848-9 - INCT 2014: INCT para Mudanças Climáticas (INCT-MC)
• Beneficiário: Jose Antonio Marengo Orsini
• Modalidade de apoio: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Temático