Report describes climate simulations for Europe

SMHI's researchers have evaluated the ability of the regional atmospheric model RCA4 to describe the climate in a reliable way. There is now a report that describes the evaluation of the model and SMHI's climate simulations for Europe.

Climate models are used to calculate how the climate will develop in future. The researchers at SMHI's Rossby Centre have now developed the capability of the regional climate model RCA4 to correctly recreate today's climate, as part of an assessment of the results from climate simulations carried out with the model. This is a necessary precondition to enable credible measurements of the future climate.

"Presently, we have more than 1500 registered users of our climate simulations, and we know that they are used in many contexts all over the world. Consequently, it is really satisfying to be able to present the results of the evaluation so that our users can find out even more about the tool we used for the measurements," says Gustav Strandberg. He is a researcher within the climate field at SMHI (Swedish Meteorological and Hydrological Institute) and the main author of the report that describes the model's capacity and climate simulations for Europe.

Results from the evaluation

The evaluation shows that the RCA4 model is fully capable of recreating today's climate and to calculate future processes. The selection of global models that the researchers at SMHI's Rossby Centre use for the regional calculations of the future climate is representative of a greater number of models.

"We test our model while we develop it and we have now carried out an extra evaluation that shows that it delivers reliable results," says Gustav Strandberg.

"A model is always a simplified description of reality. The evaluation shows that we deliver results that have the same quality as other comparable models with the same resolution."

Climate simulations for Europe and parts of the rest of the world

Rossby Centre's climate model, RCA4, is used with over one hundred climate simulations within the CORDEX collaboration. Results are diffused via SMHI's node within the Earth System Grid Federation to users across the world. The model is also used for the calculations concerning the future climate that are found on SMHI’s website.

The evaluation is described in a report, CORDEX scenarios for Europe from the Rossby Centre regional climate model RCA4. It can be downloaded from SMHI's website.

The report comprises three parts: the evaluation of RCA4's capacity to describe today's climate, the climate simulation models for Europe, together with a description of how the selection of global models that the researchers have used relates to the whole amount of available models.