Enhancing Western United States Sub-Seasonal Forecasts: Forecast Rodeo Prize Competition Series

Abstract:

The Bureau of Reclamation (Reclamation) is the largest wholesaler of water in the United States, delivering water to 31 million people, serving 20 percent of western irrigators, and generating enough hydropower to serve 3.5 million homes. Providing these services is informed by a variety of hydroclimate observation and forecast information. Improved sub-seasonal forecasts of temperature and precipitation would enable water managers to better prepare for shifts in hydrologic regimes, such as the onset of drought or occurrence of wet weather extremes.

In support of advancing sub-seasonal prediction, Reclamation launched a series of prize competitions called the Sub-Seasonal Climate Forecast Rodeos. These year-long, real-time forecasting competitions are focused on improving Western U.S. temperature and precipitation for weeks 3 & 4 and weeks 5 & 6. Rodeo I concluded in 2018 with several teams outperforming benchmark forecasts, winning $525,000 in prizes. Based on the success of Rodeo I, and the desire to further improve skill of sub-seasonal forecasts, Rodeo II was launched in 2019 and will conclude fall 2020. Rodeo II features the same year-long competition and forecasts as Rodeo I, but is open to international participation, and winning solutions from Rodeo I serve as benchmarks. Relative to Rodeo I, participation in Rodeo II has increased almost ten-fold, with many teams outperforming the benchmarks.

This presentation will provide an overview of Rodeo II experiences and final outcomes, assessing the efficacy of crowd-sourcing as a vehicle for innovation on sub-seasonal prediction. Further, it will discuss the most promising winning methods from Rodeo II for advancing sub-seasonal forecasts of temperature and precipitation in the Western United States.