Temporal evolution of the spatial covariability of rainfall in South America

Autor(es)

Ciemer, Catrin ^{[1, 2]} ; Boers, Niklas ^{[2, 3]} ; Barbosa, Henrique M. J. ^[4] ; Kurths, Jurgen ^{[1, 5, 2, 6]} ; Rammig, Anja ^[7]

Afiliação do(s) autor(es)

^[1] Humboldt Univ, Dept Phys, Berlin - Germany

^[2] Potsdam Inst Climate Impact Res, Potsdam - Germany

^[3] Ecole Normale Super, Geosci Dept, Paris - France

^[4] Univ Sao Paulo, Dept Phys, Sao Paulo - Brazil

^[5] Nizhnii Novgorod State Univ, Dept Control Theory, Nizhnii Novgorod - Russia

^[6] Univ Aberdeen, Inst Complex Syst & Math Biol, Aberdeen - Scotland

^[7] Tech Univ Munich, TUM Sch Life Sci Weihenstephan, Munich - Germany

• Tipo de documento: Artigo Científico
• Fonte: Climate Dynamics; v. 51, n. 1-2, p. 371-382, JUL 2018.
• Citações Web of Science: 2

Resumo

The climate of South America exhibits pronounced differences between rainy and dry seasons, associated with specific synoptic features such as the establishment of the South Atlantic convergence zone. Here, we analyze the spatiotemporal correlation structure and in particular teleconnections of daily rainfall associated with these features by means of evolving complex networks. A modification of Pearson's correlation coefficient is introduced to handle the intricate statistical properties of daily rainfall. On this basis, spatial correlation networks are constructed, and new appropriate network measures are introduced in order to analyze the temporal evolution of the networks' characteristics. We particularly focus on the identification of coherent areas of similar rainfall patterns and previously unknown teleconnection structures between remote areas. We show that the monsoon onset is characterized by an abrupt transition from erratic to organized regional connectivity that prevails during the monsoon season, while only the onset times themselves exhibit anomalous large-scale organization of teleconnections. Furthermore, we reveal that the two mega-droughts in the Amazon basin were already announced in the previous year by an anomalous behavior of the connectivity structure. (AU)

• Processo FAPESP: 11/50151-0 - Fenômenos dinâmicos em redes complexas: fundamentos e aplicações
• Beneficiário: Elbert Einstein Nehrer Macau
• Linha de fomento: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/50510-5 - Pesquisa colaborativa Brasil-EUA: modificações causadas pela poluição antrópica na química da atmosfera e na microfísica de partículas da floresta tropical durante as campanhas intensivas do GoAmazon
• Beneficiário: Henrique de Melo Jorge Barbosa
• Linha de fomento: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Regular