Urban Klima 2050 goes one step further in local adaptation to climate change with new climate projections for the Basque Country
31/03/2025
The latest results obtained by Euskalmet in collaboration with Neiker extend the analysis of climate risk in the Basque Country with variables such as wind speed, relative humidity or solar radiation.
The LIFE IP Urban Klima 2050 project is moving forward in the development of local adaptation measures, thanks to the work carried out by Euskalmet, Neiker and Tecnalia on the continuous improvement of climate projections for the Basque Country, using high-resolution data to anticipate future climate conditions.
The study, initiated in the first phase of Urban Klima 2050 and with additional results in 2024, is part of action A.2 Broadening the climate risk analysis in the Basque Country.
Previous results
The analysis carried out by Neiker in the first phase of the LIFE IP Urban Klima 2050 project focused on rainfall and temperature variables, resulting in more than 70 climate indicators based on these variables. The data obtained has enabled us to study three time periods (2011-2040, 2041-2070 and 2071-2100) against the historical reference period with a high spatial resolution (approximately 1km x 1km). The analysis anticipates a gradual increase in temperatures that could lead to more intense heat waves and changes in rainfall patterns.
Furthermore, the study also used the Universal Soil Loss Equation (USLE), a model widely used in erosion studies, to analyse potential soil erosion caused by changing rainfall patterns in the Basque Country. Using this equation, rain erosivity (the energy of rainfall to cause erosion), soil erodibility (how easily the soil is eroded by characteristics such as texture, organic matter content or structure) and topography (the slope and its length) factors were taken into account. As a result, specific maps were generated to estimate erosion under an extreme climate change scenario (RCP8.5) in the three aforementioned time periods.
New developments
During the second phase of the project, Euskalmet has completed the analysis with wind speed, relative humidity and solar radiation, whereby these variables delve deeper into the analysis of climate risk in the Basque Country and allow for a wider-reaching study of local conditions and their evolution over the coming decades.
To do so, Euskalmet has indicated that the projections of the climate models have been adjusted in order to bring them into line with the observational records in the region. The analysis was based on data from EURO-CORDEX, one of the most advanced regional climate projection initiatives in Europe. This initiative combines global and regional models to generate climate change simulations with a resolution of approximately 12 x 12 km, without bias corrections. E-OBS, a European climate dataset developed by ECA&D (European Climate Assessment & Dataset), which provides an extensive and high-quality record series on meteorological variables from European stations, has been used for observational records. Finally, Machine-Learning techniques applied to spatial prediction have been used to increase the resolution to the same values as the rest of the temperature and rainfall data (1x1 km) in order to facilitate operations.
In the same way as the variables analysed in the first phase of the LIFE IP Urban Klima 2050 project, the data obtained has enabled the daily series to be studied for three key periods (2011-2040, 2041-2070 and 2071-2100) and their analysis anticipates a slight downward trend in average wind speed and relative humidity, and a slight increase in radiation compared to today.
Climate projections adapted to the reality of the Basque Country
All these high-resolution projections enable more detail to be obtained than that provided by the climate models on which they are based (EURO-CORDEX models) and are therefore essential in order to carry out studies of impact and adaptation to climate change at a local level, helping to identify vulnerable areas in the Basque Country.
Twelve simulations combining five global and four regional models have been used for the analysis of temperature and rainfall. In the case of relative humidity, up to 33 global and regional models have been used, whereas 36 have been used for wind and up to 12 have been used for radiation depending on the emission scenario used (RCP8.5 and RCP4.5). In all cases, bias correction techniques have been applied to adjust the projections to the specific context of the Basque Country, thus reducing the deviations of the model and ensuring that the projected data reflect local conditions reliably.
All the information generated by Euskalmet and Neiker is available through the Ihobe Klima Scenarios viewer, which enables climate projections and their implications in the Basque Country to be explored.
