Changes in the variability modes of the South Atlantic Ocean and impacts on the climate of South America under of climate change

Abstract

In the last decades some changes of certain properties of the Atlantic Ocean, such as Sea Surface Temperature (SST), salinity and heat exchanges with the atmosphere, especially in the southern hemisphere have been verified. Thus, important forms of interaction between the ocean-atmosphere on a climate scale such as the principal mode of coupled variability of the Atlantic Ocean, known as the South Atlantic Dipole, are also subject to change. One of the main factors responsible for these changes in the Atlantic Ocean has been linked to an increase in the Needle (Agulhas) Lekeage which would be associated with climatic changes triggered by anthropogenic actions, generating an increase in the transport of relatively hotter and saltier waters from the Indian Ocean to the Atlantic. Many studies in the field of oceanography on the Agulhas Lekeage and its impact on the southern Atlantic circulation circulation have been carried out. But little is known about what impacts, through ocean-atmosphere interactions, on climate dynamics across the globe, or how these impacts have evolved over time or even how they will evolve under future global warming aspects. This study proposes to investigate the impacts of changes in the Atlantic Ocean on the climate, more specifically on the South American continent, by analyzing the modes of coupled variability of the South Atlantic Ocean and its relations with the climate in the continent from the perspective of climate changes. (AU)