Integrated measurements of GHG emissions at an intermediate port

Canada's marine transportation sector is key to its trade and prosperity and also a support system for communities and industries along our extensive coasts and lakes. However this sector is difficult to decarbonize and meeting net zero goals will require new technologies, and assessment of their effectiveness as they are introduced. Shipping fuels are changing, with green hydrogen and derivatives like methanol and ammonia competing in a race to replace bunker fuel. The shipping industry, and especially ports and harbours, will need to evaluate the direct impacts of new fuels on greenhouse gas (GHG) budgets, including when vessels are not operating efficiently, which can lead to emissions of the powerful GHG N2O. Ports are an obvious focal point for such assessments and also require data about GHG emissions to guide their own developments and operations. On the other hand, human activities can alter "natural" sources and sinks of GHGs. Marine microbes can produce N2O and they are highly sensitive to dissolved oxygen concentrations and inputs of nitrogen to harbours from wastewater and runoff. Oxygen concentrations can be altered by changed circulation of a port due to dredging or construction and by climate change and ocean warming. "Natural" emissions of GHGs from coastal waters, which can amount to at least 20% of port emissions in a given year, are therefore subject to change due to direct disturbance by port activities and indirect anthropogenic disturbances such as climate change. In partnership with the Port of Halifax and Eosense Inc. (a GHG gas sensor developer) we will: 1) establish baseline conditions and monitor impacts of new fuels on \emissions of GHGs from the marine sector; 2) determine the magnitude of GHG emissions (fluxes) from coastal waters and their sensitivity to direct and indirect anthropogenic disturbance; 3) critically evaluate the attribution of variability in atmospheric measurements to direct vs. indirect GHG emissions; 4) provide public information about GHG sources and magnitudes within the Port of Halifax. The partnership will strengthen academic-industry ties and foster a multidisciplinary training environment for students.