WSC-Category 1 Collaborative Proposal: Coupled Multi-scale Economic, Hydrologic, and Estuarine Modeling to Assess Impacts of Climate Change on Water Quality Management

1360280 Easton 1360285 Li 1360286 Najjar WSC-Category 1 Collaborative Proposal: Coupled Multi-scale Economic, Hydrologic, and Estuarine Modeling to Assess Impacts of Climate Change on Water Quality Management One of the most important questions facing our society is the potential impact of climate change on water quality, water resources and ecosystem function. Confounding issues such as urban sprawl and agricultural intensification make it difficult to determine the singular effects of climate change on water quality, ecosystem function and on the costs to achieve water quality goals. In view of the challenges facing the Chesapeake Bay (urban growth, agricultural intensification, climate change) an integrated multi-disciplinary approach is critical to provide policy makers with robust and reliable information. The approach that the research team will use is to integrate key climate, hydrologic, estuarine, and economic drivers at multiple scales which will provide water management options for the Chesapeake Bay system. One way to assess the impacts of climate change in the face of these other stressors is to develop coupled models that incorporate the pertinent controls on the water system. The overarching goal of this project is to develop a quantifiable, predictive framework that couples biogeochemical and hydrologic drivers of terrestrial nutrient export with climate change to evaluate the effects of ecosystem management on estuarine function and costs of water quality protection. To achieve this goal, the project proposes to work broadly across common regional Chesapeake Bay watershed physiographic gradients and dominant land uses (e.g., agriculture, forest and urban) using a multi-scale model evaluation of the impact of climate change and climate variability on the hydrologic, biogeochemical, and economic drivers of water quality degradation in the Chesapeake Bay estuary. Climate data will be down scaled from global and regional climate models and applied to watershed models to predict hydrologic activity and nutrient production across five test-bed watersheds where significant investments in land management (e.g., Best Management Practices) have been made. Test-bed model results will be used to populate an economic model to quantify the optimum tradeoff between water quality improvements and their associated costs. The watershed models will then be upscaled to predict hydrologic and nutrient delivery to an estuarine model to determine estuary impacts.