The impact of the presence of subtropical mode water on nutrients

• Grant number: 14/22999-2
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): December 01, 2014
• Effective date (End): November 30, 2015
• Field of knowledge: Physical Sciences and Mathematics - Oceanography
• Principal Investigator: Olga Tiemi Sato
• Grantee: Paula Birocchi
• Home Institution: Instituto Oceanográfico (IO). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The subtropical mode water is a specific type of oceanic water mass characterized by the homogeneity in both the vertical structure and its horizontal extension. The South Atlantic subtropical water Atlantic type 1 is formed between the months of June and October near the Brazil-Malvinas confluence and within the extension of the Brazil Current recirculation gyre. The formation region extends in the order of ~1000 km zonally centered at latitude 35oS and ~170 m of depth. In this research project we aim to investigate how the presence of the subtropical mode water is associated with the distribution of nutrients in the water column. Thus, tridimendional data of monthly averages of nutrients will be analyzed to determine how the mode water changes the nutrient content in the water column in the areas of formation and subduction. Data obtained from a ocean numerical model coupled with a biogeochemical model are used for a more detailed and continuous description of volume associated with the mode water, from the point of view of their nutrients.