The coastal ocean is a dynamic, complex region where multi-scale processes interact and create conditions suitable for rich ecosystems. Furthermore, the coastal ocean is substantially impacted by both climate change (e.g., alterations to temperature, freshwater discharge, sea level) and the direct impact of human activities (e.g. fishing, aquaculture, watershed nutrient and carbon inputs). Since global and regional ocean models usually lack the necessary spatial resolution to fully represent many of the processes occurring nearshore, there is a need for high-resolution coastal models. These models can be used to understand physical and biogeochemical variability associated with shallow, nearshore environments, including sediment-water exchange, benthic primary production, and complex shorelines and bathymetry. This complexity within coastal regions, both in terms of geography and physical and biogeochemical dynamics, makes these modeling exercises challenging, region-specific, and applicable to a host of fundamental and applied questions. Nevertheless, commonalities can be drawn among different regions and models, such that the modeling community can benefit immensely by sharing experiences and results. Therefore, we call for contributions on coupled physical-biogeochemical models of different coastal regions, from estuaries and near-shore environments to enclosed seas and continental shelves. Our goal is to provide a forum to discuss and learn from the challenges faced in different geographic regions and with different model architectures.