The Study for Exascale Advances in a High-resolution Ocean using ROMS Coupled to E3SM (SEAHORÇE) SciDAC5 project will focus on improved representations of small-scale coastal and open-ocean processes such as river plumes, coastal fronts, and meso- and submesoscale eddy processes. We will do this by creating and evaluating a new component of the Energy Exascale Earth System Model (E3SM), based on the Regional Ocean Modeling System (ROMS), a community standard coastal ocean model that has been in use for over two decades. The overarching goal of the project is to improve the ability of E3SM to model oceans with higher fidelity than currently possible.  To achieve this goal, we plan to pursue the following specific objectives:

1. extend the resolution capabilities of MPAS-O through coupling with a limited-domain, high-resolution, regional ocean model (ROMS).
2. create a scientific and technical framework for efficient and robust two-way coupling of ROMS within MPAS-O that exploits the latest HPC architectures.
3. characterize and parameterize the impact of small-scale processes, unresolved in current climate models, on climate projections.