This project aims to develop an optimized, variable-resolution grid for the Energy Exascale Earth System Model (E3SM)’s ocean component - the Model for Prediction Across Scales ocean model (MPAS-O) to enhance marine ecosystem simulations within the E3SM framework. The project will also incorporate an expanded complexity marine ecosystem model (MARBL-8p4z) that improves model capabilities to respond to climate change and other perturbations with realistic shifts in the phytoplankton and zooplankton communities and plankton physiology. This innovative approach is expected to significantly improve predictions of ocean circulation and biogeochemical processes, impacting climate modeling and biogeochemistry-climate feedback studies while maintaining computational efficiency. The hypothesis is that the variable-resolution approach will enable the model to better capture important biogeochemical processes associated with coastal upwelling systems, oxygen minimum zones, and the lower overturning cell in the Southern Ocean. Integrating advanced biogeochemical modeling techniques with a variable-resolution grid is a novel contribution to climate modeling.

The work is expected to deliver a more capable ocean modeling framework tailored to investigating biogeochemical processes. The results could significantly impact climate modeling and marine biogeochemistry by providing more accurate and comprehensive predictions of biogeochemical processes and their interactions with climate dynamics. 

The results of this work would be of great value and interest to other groups, who can adopt the resulting refined model grid for their own research. Once the optimized, variable-resolution grid E3SM framework is developed, the team plans to examine how varying grid resolution in the Southern Ocean deep water formation regions impacts the strength of Southern Ocean meridional circulation (SMOC), through a water mass analysis approach that helps identify biases and their causes. They will also examine how variability in Antarctic Bottom Water (AABW) formation and SMOC rates influence global scale nutrient distributions and ocean carbon storage.