Relationship of South Atlantic Meridional Overturning Circulation and South Atlantic Monsoons

• Ano de defesa: 2025
• Autor(a) principal: Júnior, Luiz Carlos da Silva Netto
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: African Monsoon; Célula de Revolvimento Meridional do Atlântico Sul; Extended Empirical Orthogonal Function; Função Ortogonal Empírica Extendida; Interação Oceano-Atmosfera; Mapa de Autoorganização; Monção Africana; Monção da América do Sul; Ocean-Atmosphere Interaction; Ondaleta; Self Organization Map; South American Monsoon; South Atlantic Meridional Overturning Circulation; Wavelet
• Link de acesso: https://www.teses.usp.br/teses/disponiveis/21/21135/tde-11082025-153444/

The biosphere is given shape by changes on the atmosphere and the ocean what turns the understanding of climate changes extremely important to keep the life conditions for the ecosystems and the human being. The radiative budget happens when the solar radiation amount which enters on the atmosphere is balanced by the quantity that leaves and studies responsibles for to find out the mechanisms that keep are the base to prevent the climate change. The main mechanisms for distribution of the heat on the atmosphere and the ocean are the MOCs. The hypothesis to be tested by the present work is the relationship among the SAMOC and South Atlantic Monsoons is connected to the relationship between the ACC and the ITCZ. The present work aims to investigate how the oceanic and atmospheric circulations interfere with the Antarctic and ITCZ circulations. The work followed the steps: the models were validated with Taylor Diagram to avail the similarity between the model and the reality; FFT were realized for identification of the main scales that compose the data; EEOF to obtain the patterns of precipitation, wind, heat transport and salt transport of the models outputs; Homogeneous and heterogeneous correlation maps were calculated in a way to infer the agreement among the combination of the patterns of all the variables; Wavelet analysis to identify the variation of energy among the scales; nonlinear PCA by SOM to obtain the nonlinear interaction patterns of precipitation, wind, heat transport and salt transport of the models outputs; DecisionTree, RandomForest, DecisionStump and Adaboost and PCA for the evaluation of the decision of which interactions between variables are more relevant to the data. The Taylor Diagram showed 50%-70% of correlation for both models; FFT showed dominance of scales greater than 10 years of period; EEOF showed patterns that can indicate the migration of ITCZ southward on the MPI and northward on the MRI as highlights regions of the NBC, BMC, AC, SAC and SEC; Correlation Maps showed the contribution in terms of rotation of the wind and convergence and divergence of the heat and salt transport; Wavelets showed exchange of energy between 10, 15 and 20 year scale; SOM showed patterns on the regions of the ITCZ and ACC and monsoons regions; DecisionTree showed Vs vs pr and pr vs Us vs Uh vs u, RandomForest showed acuracy of time 30%-60% and space 14%, DecisionStump showed v vs pr, Vs vs pr and Us vs pr, and Adaboost showed acuracy of time 50% and space 30%-40%. There is a possibility but not definitive that the connection between the ITCZ and ACC relationship and the SAMOC and South Atlantic Monsoons relationship can be the SEC and SAC.