About 40% of the global population lives within proximity of the coast and this number is projected to increase dramatically by 2100. Most megacities are also located by the ocean. The impacts that these foci of human activities have on land use, runoff, hydrodynamics, atmospheric deposition and local climate directly influence the biogeochemistry and water quality of adjacent coastal waters. These urban coastal systems are also experiencing increasing pressures due to rapid climate- and human-driven changes (e.g., sea-level rise, enhanced storm activity, population growth, urban development, etc), and there is a critical need to better understand and predict how biogeochemical processes and their connection to water quality are responding to these changes. The purpose of this session is to share recent advances in our understanding of how cities influence the biogeochemistry in coastal waters. This session invites observational, experimental, and biogeochemical modeling studies of any urban coastal system from around the world. Interdisciplinary and modeling studies that improve the quantitative understanding of processes and how they are or will be impacted by human activities and climate change are particularly welcome. 

Studies that focus more on basic knowledge of biogeochemical processes associated with urban water quality should submit to this session. Abstracts that focus more on data products, applications, and operational services should submit to the "Water quality monitoring and forecasting in coastal waters: Applications and operational services" session.