Wu, W., and Mahadevan, A. (2024)
Presented at:
Ocean Sciences Meeting 2024Despite its prevalence in the global ocean, eddy splitting has not previously been associated with the vertical transport of biogeochemical tracers at submesoscales. Our research suggests that there is an increase in surface chlorophyll concentrations for anticyclone splitting events and a decrease for cyclone splitting events. Using a process study ocean model, we find that, for anticyclone splitting, the dominant obduction component of the vertical transport leads to a supply of nutrients from depth to the euphotic zone, which may explain the observed surface phytoplankton growth during the splitting events in nutrient-limited regions. For a cyclone that splits, the subduction component dominates, which helps to explain the observed decay of surface phytoplankton. From NASA's ECCO LLC2160 state estimate, we highlight the efficacy of high-resolution sea surface height (SSH) fields for capturing eddy splitting events and show that cyclones split more frequently than anticyclones at submesoscales. We will investigate the mechanisms behind this asymmetry. The potential ubiquity of cyclone splitting at submesoscales may play a key role in subducting ocean carbon at surface. The ongoing SWOT mission offers a unique opportunity to validate eddy splitting statistics at submesoscales.
