About Copernicus C3S multi-model ensemble seasonal forecasts
From 10 May 2025 the Bureau's operational forecast model, ACCESS-S2, joined other international models on the Copernicus Climate Change Service (C3S).
Copernicus C3S is implemented by the European Centre for Medium-Range Weather Forecasts (ECMWF).
Copernicus C3S provides a multi-model ensemble of seasonal atmospheric and ocean forecasts from leading international centres from around the world. These forecasts extend out to six months into the future and are updated on the 10th of every month. Graphs for a variety of variables such as air temperature, wind speed, precipitation and sea surface temperature are displayed at different lead times on the C3S website. The combined model data is also served publicly through Copernicus Climate Data Store (CDS).
How are the combined models useful in forecasting?
Each model simulates the Earth system processes that influence weather patterns in slightly different ways, leading to different kinds of model error. Combining the output from a range of models enables a more realistic representation of the uncertainties, giving a clearer picture of the potential outcomes. Using multi-model ensembles can improve forecast skill by averaging results from different models, which helps reduce errors and biases of the individual models.
Benefits for Australian and international communities
Our forecasts join those from ECMWF UK Met Office, Météo-France, the German Weather Service (DWD), the Euro-Mediterranean Center on Climate Change (CMCC), the US National Weather Service's NCEP (NCEP), Japan Meteorological Agency (JMA) and Environment and Climate Change Canada (ECCC).
The Bureau's contribution to C3S will lead to future improvements in weather and climate products and services in Australia. It will also provide new opportunities for climate modelling and joint research for the benefit of European and Australian communities.
More information
To see the multi-model forecasts, head to: Charts | Copernicus
