Ensemble streamflow forecasting experiments in a tropical basin: The São Francisco river case study

- Ensemble forecasting application to a large tropical river basin in Brazil.
- Test case where forecasts are important for reservoir operation and flood control.
- Results showed benefits in the use of ensembles for the reservoir inflow.
- Difficulties, future challenges and improvements are explained and discussed.

SummaryThe present study shows experiments of ensemble forecasting applied to a large tropical river basin, where such forecasting methodologies have many potential applications. The case study is the Três Marias hydroelectric power plant basin (Brazil), on the São Francisco river, where forecast results are particularly important for reservoir operation and downstream flood control. Results showed some benefits in the use of ensembles, particularly for the reservoir inflow on flooding events, and in comparison to the deterministic values given by the control member of the ensemble and by the ensemble mean. The study also discusses the improvements that must be tested and implemented in order to achieve better results, what is particularly important for the smaller basins within the study case. Despite the necessary improvements mentioned, the results suggest that benefits can result from the application of ensemble forecasts for hydropower plants with large basins within the Brazilian energy system.