A comparison between ensemble and deterministic hydrological forecasts in an operational context

摘要

Ensemble forecasts can greatly benefit water resources management as theyprovide useful information regarding the uncertainty of the situation athand. However, weather forecasting systems are evolving and the cost forreanalysis and reforecasts is prohibitive. Consequently, series of ensembleweather forecasts from a particular version of the forecasting system areoften short. In this case study, we consider a hydrological event that tookplace in 2003 on the Gatineau watershed in Canada and caused managementdifficulties in a hydropower production context. The weather ensembleforecasting system in place at that time is now obsolete, but we show thatwith minimal post-processing of the forecasts, it is still beneficial toexploit ensemble rather than deterministic forecasts, even if the latteremerge from a more advanced meteorological model and possess superiorspatial resolution.