Late Holocene Precipitation Fluctuations in South America Triggered by Variability of the North Atlantic Overturning Circulation

Autor(es):Mostrar menos -

Bahr, A. ^[1] ; Kaboth-Bahr, S. ^{[1, 2]} ; Jaeschke, A. ^[3] ; Chiessi, C. ^[4] ; Cruz, F. ^[5] ; Carvalho, L. ^[6] ; Rethemeyer, J. ^[3] ; Schefuss, E. ^[7] ; Geppert, P. ^[1] ; Albuquerque, A. L. ^{[5, 8]} ; Pross, J. ^[1] ; Friedrich, O. ^[1]

Afiliação do(s) autor(es)

^[1] Heidelberg Univ, Inst Earth Sci, Heidelberg - Germany

^[2] Univ Potsdam, Inst Earth Sci, Potsdam - Germany

^[3] Univ Cologne, Inst Geol & Mineral, Cologne - Germany

^[4] Univ Sao Paulo, Sch Arts Sci & Humanities, Sao Paulo - Brazil

^[5] Univ Sao Paulo, Inst Geosci, Sao Paulo - Brazil

^[6] Univ Calif Santa Barbara, Dept Geog & Earth Res Inst, Santa Barbara, CA - USA

^[7] Univ Bremen, MARUM Ctr Marine Environm Sci, Bremen - Germany

^[8] Univ Fed Fluminense, Dept Geoquim, Niteroi, RJ - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY; v. 36, n. 9 SEP 2021.
• Citações Web of Science: 0

Resumo

Historic droughts document the strong spatio-temporal variability of the South American Monsoon System, which currently provides more than two thirds of the rainfall in tropical South America. The drivers of this variability have remained not well understood due to the lack of continuous, high-resolution paleorecords, especially from the more arid regions of tropical South America. Here we present a novel record of moisture availability across eastern South America for the past similar to 5,000 years from a sediment core retrieved off eastern Brazil. We document distinct decadal- to millennial-scale spatial shifts of major atmospheric convection centers that caused increasingly pronounced droughts in eastern South America over the past similar to 2,000 years. These fluctuations were triggered by climate anomalies in the high northern latitudes and propagated into equatorial latitudes via fluctuations in North Atlantic Overturning Circulation strength. As global warming is expected to decrease oceanic overturning due to enhanced meltwater input into the North Atlantic while at the same time reducing precipitation over eastern South America, an increasing risk for long-lasting droughts can be expected for this region, posing severe socio-economic challenges. (AU)

• Processo FAPESP: 18/15123-4 - Perspectivas pretéritas sobre limiares críticos do sistema climático: a Floresta Amazônica e a célula de revolvimento meridional do Atlântico (PPTEAM)
• Beneficiário: Cristiano Mazur Chiessi
• Modalidade de apoio: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Jovens Pesquisadores - Fase 2
• Processo FAPESP: 17/50085-3 - PIRE: educação e pesquisa em clima das Américas usando os exemplos de anéis de árvores e espeleotemas (PIRE-CREATE)
• Beneficiário: Francisco William da Cruz Junior
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 19/24349-9 - Avaliando os efeitos das mudanças climáticas do passado e do futuro na biodiversidade amazônica (CLAMBIO)
• Beneficiário: Cristiano Mazur Chiessi
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Regular