Assessment of Folsom Lake response to historical and potential future climate scenarios: 2. Reservoir management

An integrated forecast–decision system for Folsom Lake (California) is developed and used to assess the sensitivity of reservoir performance to various forecast–management schemes under historical and future climate scenarios. The assessments are based on various combinations of inflow forecasting models, decision rules, and climate scenarios. The inflow forecasting options include operational forecasts, historical analog ensemble forecasts, hydrologic ensemble forecasts, GCM-conditioned hydrologic ensemble forecasts, and perfect forecasts. Reservoir management is based on either heuristic rule curves or a decision system which includes three coupled models pertinent to turbine load dispatching, short-range energy generation scheduling, and long/mid-range reservoir management. The climate scenarios are based on historical inflow realizations, potential inflow realizations generated by General Circulation Models assuming no CO2 increase, and potential inflow realizations assuming 1% CO2 annual increase. The study demonstrates that (1) reliable inflow forecasts and adaptive decision systems can substantially benefit reservoir performance and (2) dynamic operational procedures can be effective climate change coping strategies.