Water Resources Research Act Program

Details for Project ID 2017PA230B

Toward Improved Predictability of Sub-seasonal to Seasonal Streamflow in Pennsylvania

Institute: Pennsylvania
Year Established: 2017 Start Date: 2017-03-01 End Date: 2018-02-28
Total Federal Funds: $19,885 Total Non-Federal Funds: $38,890

Principal Investigators: Alfonso Mejia

Abstract: Streamflow quantity and quality are vital to the economy and well-being of Pennsylvania since streamflow is a primary source of freshwater to many industries and communities in the State. To ensure and monitor the availability of streamflow, it is necessary to predict streamflow at a range of temporal and spatial scales. Normally, streamflow predictions in Pennsylvania have been performed at the weather (<14 days) or climate (>1 year) scales, with the subseasonal to seasonal (S2S) scale (between 14 days and 12 months) representing an important research and operational gap. The objective of this project is to overcome this prediction gap by producing and evaluating S2S streamflow predictions for selected basins in Pennsylvania. Historically, S2S streamflow predictions in Pennsylvania have been of low quality, mainly because of the lack of skillful climate predictions in the S2S range. Indeed, the S2S range represents a new and rapidly growing frontier for progress and advancements in weather and climate research. Recent progress in S2S climate predictions (associated with the use of better models, higher-resolution outputs, and improved data assimilation methods and observing systems) suggest that improve S2S streamflow predictions may be attainable in Pennsylvania. The proposed research will use recent outputs from the newest S2S climate models to force a distributed hydrological model (WRF-Hydro) in Pennsylvania and generate S2S streamflow predictions. The period between 2002 and 2016 is selected for this study to match the available multisensor precipitation estimates (MPEs) data. The MPEs will be used as the observations to verify the climate predictions and to generate hydrological hind casts for comparison purposes. The use of MPEs is noteworthy since they are the highest quality precipitation forcing available for Pennsylvania but are rarely used to force and verify predictions from distributed hydrological models in Pennsylvania. For the hydrological model and climate predictions, the WRF-Hydro and Climate Forecast System (CFS) will be used, respectively, since they represent state-of-the-art modeling and prediction systems. Completion of this project will result in improved S2S streamflow predictions in Pennsylvania, with results that could potentially be applied to a number of water-related problems. For example, the operation of dams and water reservoirs in Pennsylvania requires having accurate and reliable S2S streamflow predictions. Likewise, the issuance of timely and effective flood warnings, environmental flow management, and drought monitoring rely on seasonal streamflow predictions to improve decision making and better serve the general public.