DEVELOPMENT OF A EUROPEAN MULTIMODEL ENSEMBLE SYSTEM FOR SEASONAL-TO-INTERANNUAL PREDICTION (DEMETER)

TLDR

DEMETER addresses key challenges—interdisciplinary communication, climate downscaling, and probabilistic forecast use—to demonstrate the societal economic value of seasonal‑to‑interannual predictions. DEMETER integrates seven global atmosphere–ocean coupled models, each run as an ensemble of initial conditions. The multimodel ensemble demonstrates superior reliability and skill versus single‑model ensembles, and its seasonal forecasts are applied to malaria and crop yield predictions.

Abstract

A multi-model ensemble-based system for seasonal-to-interannual prediction has been developed in a joint European project known as DEMETER (Development of a European Multimodel Ensemble Prediction System for Seasonal to Interannual Prediction). The DEMETER system comprises seven global atmosphere–ocean coupled models, each running from an ensemble of initial conditions. Comprehensive hindcast evaluation demonstrates the enhanced reliability and skill of the multimodel ensemble over a more conventional single-model ensemble approach. In addition, innovative examples of the application of seasonal ensemble forecasts in malaria and crop yield prediction are discussed. The strategy followed in DEMETER deals with important problems such as communication across disciplines, downscaling of climate simulations, and use of probabilistic forecast information in the applications sector, illustrating the economic value of seasonal-to-interannual prediction for society as a whole.