Coupled physical-biogeochemical modeling of the Southwestern Tropical Atlantic

In the Southwestern Tropical Atlantic (SWTA), oceanic processes contribute to the balance and temporal evolution of nutrient cycles inside the euphotic zone. ROMS coupled with Pelagic Interaction Scheme for Carbon and Ecosystem Studies (PISCES) is used to simulate the seasonal cycle of circulation/biogeochemistry. An isotropic horizontal grid resolution of 1/12º and 40 vertical levels is used. Model results show good agreement with the observational Brazilian REVIZEE program. The horizontal and vertical comparisons at the REVIZEE/SCORE-NE region (0º30’N-14º00’S; 31º24’-42º00’ W) show that a coupled physical-biogeochemical approach can represent seasonal nutrients cycles along water depth, even if this region is considered as an oligotrophic zone. These results point to a future ROMS-PISCES application using long term interannual forcings to estimate the biogeochemical evolution in the SWTA under climate change scenarios.

The authors thank the Brazilian National Council of Scientific and Technological Development - CNPq under the scope of the Project BIO-NE (Grant 558143/2009-1).

(Fabiana S. Leite, Marcus A. Silva, Moacyr Araujo - Laboratory of Physical and Coastal Oceanography at the Oceanography Department (LOFEC/DOCEAN) and Center for Risk Analysis and Environmental Modeling (CEERMA), Federal University of Pernambuco).