Projected Changes of the Southwest Atlantic circulation (P-SWAC)
Vincent Combes - Principal Investigator
I am currently a Ramón y Cajal with double affiliation (IMEDEA / UIB, Mallorca, SPAIN) since summer 2022. Previously, I have been a Senior Research Associate at Oregon State University, in the CEOAS department since 2010. I received my Phd from Georgia Tech (Atlanta) in 2010 and an engineering degree in Hydraulics from the ENSEEIHT (France) in 2005.
I am specialized in modeling realistic ocean flows in regional and coastal seas including the Gulf of Alaska, California Current, Peru Chile Current system, Patagonian shelf and Southeast Atlantic.
I am particularly interested in the low frequency ocean variability, coastal and shelfbreak upwellings, eddy dynamics, transport of nutrient rich shelf water to the deep ocean and remote sensing.
For more information visit my website at www.vincentcombes.com
Team Members
A. DelgadoG. HernánR. MatanoE. Palma
Summary of the Project
Cross-shelf exchanges play a critical role in global biogeochemical cycles, facilitating transfers of heat, salt, and organic matter between continental shelves and the deep ocean. These exchanges account for up to half of the biological pump's organic matter transfer to the deep ocean. However, their characterization is challenging due to their complex temporal and spatial scales. This process plays a pivotal role in regions like the Southern Ocean, where high productivity is linked to exchanges originating at the shelf regions.
The Southwest Atlantic, particularly at the Confluence of the Brazil and Malvinas currents, is a major area for studying cross-shelf exchanges. At the interface between the Southern Ocean and South America, this region is crucial for understanding the South Atlantic Oceans productivity, where chlorophyll-a concentrations are notably higher than in other ocean basins, driven by inputs from the continental shelf. Changes in the regional ocean circulation have therefore profound implications for local ecosystems, fisheries, and broader oceanic biogeochemical processes.
Here, we propose to evaluate the Projected Change of the Southwest Atlantic Ocean Circulation, in particular how the cross-shelf exchanges will evolve under global warming scenarios. Current projections, from the Coupled Model Intercomparison Project (CMIP), suggest an intensification and poleward- shift of the Southern Hemisphere westerly winds, an increase ocean stratification, and a strengthening of the subtropical gyre and Brazil Current. However, the coarse-resolution CMIP models are unable to resolve critical regional features like shelf circulation and cross-shelf exchanges, limiting their predictive capability for local and global productivity changes.
To address these limitations, we propose downscaling CMIP experiments using high-resolution ocean models. These models will better resolve the Southwest Atlantic's physical processes, including shelf circulation and cross-shelf exchanges. The project aims to evaluate the projected changes of these processes under different global warming scenarios, quantify cross-shelf exchanges, and investigate their implications for regional and global biogeochemical cycles. The findings will inform strategies for improving the accuracy of global models and enhance our understanding of climate change impacts on ocean ecosystems.
