From Determinism to Probability: Development of the Ensemble Prediction Technique for Weather and Climate Forecasting

Explore a comprehensive lecture from the 4th Kyoto University-Inamori Foundation Joint Kyoto Prize Symposium where Royal Society Research Professor Tim Palmer discusses the evolution of weather and climate forecasting from deterministic methods to probabilistic ensemble prediction techniques. Learn about the historical progression of weather prediction from ancient Babylonian times through the digital computer era, and understand why precise weather forecasts are inherently impossible due to chaos theory. Discover how ensemble prediction revolutionized meteorological science by running multiple forecast models with slightly varied initial conditions to generate probability distributions of possible outcomes. Examine the innovative techniques developed to ensure reliable forecast probabilities, including the use of singular vectors and stochastic parametrizations. Understand the practical value of ensemble forecasting through decision-theoretic models that help users determine when to take protective action against adverse weather events. Gain insight into how ensemble prediction has become the standard forecasting tool across all timescales in modern meteorology, from daily weather to century-scale climate change predictions.