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Puget Sound Georgia Basin Model

pH Model Formulation

Approach: pH Simulation and Acidification in the Salish Sea

The existing model of the Salish Sea, conducts carbon-based biogeochemical simulations and is well suited for incorporating acidification kinetics. The approach selected by the project team was to modify the existing FVCOM-ICM model to include relevant new quantities in the computational domain. Specifically, total dissolved inorganic carbon (TDIC) and alkalinity will be included as state variables in advection, transport, and turbulent mixing computations. Aragonite saturation and pH will be secondary quantities computed based on predicted values of TDIC and alkalinity. Because modeling acidification in estuarine waters such as Puget Sound and the Georgia Basin is relatively new, PNNL, Ecology, and EPA have initiated a collaborative process with scientists specializing in ocean acidification to develop an approach and framework that is scientifically valid and useful. The resulting report titled Approach for Simulating Acidification and the Carbon Cycle in the Salish Sea to Distinguish Regional Source Impacts (Long et. al 2014) describes our approach in detail.This first step is a precursor to a Quality Assurance (QA) Project Plan that would be developed prior to the initiating model development.

Model Kinetics

(review in progress)





Salish Sea Model

Ocean Acidification