The weather files engineers use to design buildings are built from decades of historical measurements. The data can be over 30 years old. But a building designed today is expected to perform well in 2080, and ideally beyond. Researchers from Norway and Portugal have now released future meteorological data covering more than 5,000 European locations. The files are reliable projections of Europe’s future climate, down to specific time periods and places. The entire dataset is freely available at climatedataforbuildings.eu.
“The gap between the climate conditions we use in our calculations and the climate the building will experience could exceed half a century,” says Professor Thomas K. Thiis of the Norwegian University of Life Sciences (NMBU).
Together, researchers from NMBU in Norway and the University of Coimbra in Portugal, have developed and evaluated future weather files that allow buildings to be designed for the climate they will experience.
A Typical Meteorological Year, or TMY, is the standard climate input for every building energy simulation, from a single house to a hospital campus. TMYs are assembled from historical observations, so they describe the climate of the past. But buildings designed today will experience a different climate. A Future Meteorological Year (FMY) applies climate-change projections to the historical baseline. It produces an hourly weather file for a specified future period and an emissions scenario that can be used directly in existing simulation software.
Not all climate models are equal
In a new study published in the Journal of Building Performance Simulation, researchers have evaluated a large pool of global and regional climate models. They identified those that reproduce summer and winter conditions across Europe satisfactorily, and only these selected models were used to generate the FMYs. The resulting files rest on the most reliable projections available for the European continent.
FMYs were produced for mid-century (2036-2065) and late-century (2066-2095) under multiple emissions pathways, spanning CMIP5 (RCP4.5 and RCP8.5) and CMIP6 (SSP1-2.6 through SSP5-8.5) scenarios. The choice of scenario directly affects design conclusions. In effect, this makes it a risk decision for the building project rather than a purely scientific question.
Whether a building is designed for a low-emissions or a high-emissions scenario can influence design solutions, for example regarding solar shading and cooling.
Consistent with today’s data – for the first time
The FMYs are built on the same foundation as the team’s recently published TMY dataset, which covers over 5,000 European locations and is based on the Copernicus CERRA reanalysis. For the first time, historical and future weather files for building simulation are internally consistent – produced from the same reference period, the same spatial resolution, and the same methodology.
“Engineers can now be sure that the climate change signal of the FMYs is not over- or under-estimated due to methodological mismatch,” says co-author Eugénio Rodrigues, head of CURA Lab at the University of Coimbra in Portugal.
Winter warming hits hardest where it matters most
The data reveals that temperature increases across Europe are unevenly distributed throughout the year. In northern locations such as Oslo, monthly mean temperatures rise most in winter and comparatively little in summer. Because heating dominates building energy use in northern and central Europe, even a moderate change in annual mean temperature can translate into a disproportionately large shift in energy demand.
“When the warming is concentrated in the season when energy consumption is at its highest, it has a major impact on the calculations,” says Thiis.
Already in use across Europe
Researchers in several countries, including Denmark, Poland and Spain, are already using the dataset in their work on building energy performance and climate adaptation. This signals a long-standing demand for consistent, simulation-ready future climate data in Europe.
