Orbital forcing and the evolution of South American Monsoon from late Miocene to early Pliocene

• Grant number: 23/02970-9
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: April 01, 2024
• Status: Discontinued
• Field of knowledge: Physical Sciences and Mathematics - Oceanography - Geological Oceanography
• Principal Investigator: Luigi Jovane
• Grantee: Allana Queiroz de Azevedo
• Host Institution: Instituto Oceanográfico (IO). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 16/24946-9 - Sea-level changes and Global Monsoon System: clues from marine cores in Brazil, AP.PFPMCG.TEM
• Associated scholarship(s): 24/06531-2 - Orbital Forcing and the evolution of the South American Monsoon from Late Miocene to Early Pliocene, BE.EP.PD

Abstract

Monsoonal regions worldwide are key locations that shelter several people lives. In South America, limited data hampered our knowledge about the future of South American Monsoon System (SAMS), and thus it remains unclear how it will behave facing the global warming. To constrain accurate models about future monsoon rainfall is critical evaluate paleoclimate data, and thus we will seek reconstruct the SAMS variability from late Miocene to early Pliocene through sedimentary records of the Brazilian Equatorial Margin (BEM). To achieve this goal, we will construct and astronomically calibrated age model, analyse the isotope signal of planktonic and benthic foraminifera (´18O, ´13O), analyse the (paleo)vegetation under influence of SAMS (palynological analysis) and reconstruct the pCO2 levels of the atmosphere bases on ´11B of planktonic foraminifera. By this we hope to address the following: 1) comprehend the relationship between sea-level fluctuations on the Brazilian continental shelf, atmospheric CO2 levels, and the SAMS from late Miocene to early Pliocene; 2) Did the SAMS vary according to the atmospheric CO2 levels along those time intervals?; 3) Colder temperatures at the thermocline accompanied higher emissions of CO2 to atmosphere?; 4) Did the depletion of heat content from the thermocline in the South Atlantic work as positive feedback amplifying the orbital forcing? (AU)