Multi-model seasonal forecasts available in the DST


Temperature and wind speed multi-model predictions based on four forecasting systems are now available in the S2S4E Decision Support Tool for 3 months ahead (seasonal forecasts).

The operational tool of the S2S4E project, the Decision Support Tool (DST), offers seasonal forecasts for the next 3 months aimed at the renewable energy sector. Currently, the SEAS5 ECMWF seasonal system is used to generate these predictions.

No single forecasting system can provide accurate predictions for all geographic regions and all times of the year. Because of the complexity of the Earth system and errors of individual prediction systems, there is always some degree of uncertainty in forecasts. In order to reduce the uncertainty related to these errors, the output of several systems can be combined into a multi-model forecast, which extracts a robust signal based on information shared by most of the systems.

The DST now offers users multi-model seasonal forecasts for temperature and wind speed, available in the Essential Climate Variables list. These forecasts are constructed based on four systems, all of which are provided by the Copernicus Climate Change Service (C3S). These systems are the ECMWF SEAS5, Météo-France System 7, Deutscher Wetterdienst (DWD) System 2 and CMCC System3.

While the skill of both the ECMWF and multi-model forecasts for the seasonal time-scales are similar, advanced users can benefit from this additional information by comparing these forecasts. The multi-model approach may provide more robust predictions in specific regions or for a certain time of year. Multi-model forecasts are also available by country.

Multimodel comparison

Comparison of multi-model (left) and ECMWF (right) forecasts for temperature, showing the below normal (blue), normal (yellow) and above normal (red) terciles. Issue date: June 2020; forecast time: August 2020.

Other new features implemented in the DST include: 

  • The coordinates of each grid point appear on the map.
  • Users can now search for specific coordinates (or locations) using the search box at the top bar.

For more information on the multi-model forecasts, refer to the Advanced help page of the DST. It should be noted that sub-seasonal multi-model forecasts for 1-4 weeks ahead are not available.

Written by: Andria Nicodemou (BSC)