The impacts of deglacial meltwater forcing on the South Atlantic Ocean deep circulation since the Last Glacial Maximum

Autor(es)

Marson, J. M. ^[1] ; Wainer, I. ^[1] ; Mata, M. M. ^[2] ; Liu, Z. ^{[3, 4]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Oceanog, Sao Paulo - Brazil

^[2] Fundacao Univ Fed Rio Grande, Inst Oceanog, Rio Grande, RS - Brazil

^[3] Univ Wisconsin, Ctr Climat Res, Madison, WI - USA

^[4] Univ Wisconsin, Dept Atmospher & Ocean Sci, Madison, WI - USA

• Tipo de documento: Artigo Científico
• Fonte: Climate of the Past; v. 10, n. 5, p. 1723-1734, 2014.
• Citações Web of Science: 6

Resumo

A NCAR-CCSM3 (National Center for Atmospheric Research - Community Climate System Model version 3) state-of-the-art transient paleoclimate simulation with prescribed freshwater inflows is used to investigate the changes and evolution of the South Atlantic water mass structure from the Last Glacial Maximum (LGM) to the present day. Model results show that 21 000 yr ago the water column was substantially stratified due to the presence of a saltier-than-today Antarctic Bottom Water (AABW), forming a salinity barrier that prevented dense waters from the Northern Hemisphere from sinking. This salinity barrier started to erode after the termination of the Heinrich event 1, when its associated meltwater was transported southward, freshening the AABW. The removal of the barrier after 14 ka triggered the production of the North Atlantic Deep Water (NADW), which spread into the deeper layers of the South Atlantic at the onset of the Holocene. At this point, the NADW acquired its modern-day structure, establishing a deeper Atlantic meridional overturning circulation (AMOC). (AU)

• Processo FAPESP: 11/02047-9 - Pulsos de água doce na transição do Último Máximo Glacial: impactos na estrutura física e dinâmica do Oceano Austral
• Beneficiário: Juliana Marini Marson
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 13/02111-4 - Investigação da evolução do oceano profundo na região do Atlântico Sul para o último milênio: impactos para a mudança do clima
• Beneficiário: Ilana Elazari Klein Coaracy Wainer
• Modalidade de apoio: Bolsas no Exterior - Pesquisa