Evaluating Community Watershed Models and Observation Networks within the Susquehanna River Basin
September 23, 2009
The Susquehanna River Basin is the largest tributary to the Chesapeake Bay, providing more than 60 percent of its freshwater inflow. Without this flow the estuary could not sustain its extraordinary diversity and productivity of aquatic life. Management of the Susquehanna requires a balance between the competing societal and environmental demands placed on its freshwater resource.
Patrick Reed and Thorsten Wagener, both associate professors in the department of civil and environmental engineering, will address key questions about that balance, focusing specifically on how humans and climate impact the sustainability of the water resources within large river basins.
“We seek to transform our ability to detect and/or predict the impacts of long-term changes on the hydrology of the Susquehanna. Our ability to understand human-climate impacts on the river basin’s environmental systems requires a paradigmatic shift towards community level evaluations of the predictive power of watershed models, as well as adaptive design of the basin-scale observation networks under conditions of uncertainty,” say the researchers.
This work will contribute time-evolving sensitivity maps for a suite of models that will allow Reed, Wagener and their students to explore how hydrologic flow changed during strong climate fluctuations in the last decade (e.g. from the drought in 2001 to wet conditions in 2003). The sensitivity maps will then be used to identify the key uncertainties to be incorporated into an ensemble based data assimilation framework that explicitly considers systematic sources of bias in observations and model structures. This framework will provide baselines for judging the forecasting skills of models as well as the value of observations in the decades to come.