Vall de Núria (Queralbs), 21 September 2026. By the end of the century, the Pyrenees could experience summer temperatures nearly 5°C higher than during the 1985–2015 period under a highly likely intermediate-to-high emissions scenario, while observed data show that warming is intensifying particularly between 1,500 and 2,200 metres above sea level, where maximum temperatures have risen by 1.8°C and minimum temperatures by 2.1°C over the past 24 years.

The new projections also point to a decline in precipitation, particularly during summer, with an average expected deficit of close to 15%. This scenario is compounded by changes already detected in the snowpack, with uneven losses depending on altitude and mountain area, and a significant increase in snow droughts.

These are some of the results and advances presented on Monday at the “Technical workshop on climate scenarios and territorial adaptation in the Pyrenees: first results from the LIFE Pyrenees4Clima project”, held on 21 and 22 September in Vall de Núria and attended by around 90 experts from different fields. The project — which brings together 47 partner organisations from across the Pyrenees — is led by the Pyrenean Climate Change Observatory (OPCC) and aims to turn scientific knowledge about climate trends into concrete adaptation tools and solutions for Pyrenean territories.

The workshop has provided an opportunity to share new knowledge and reflect on how to integrate it into climate action. During the event, results and progress have been presented in seven complementary areas: climate change indicators in the Pyrenees; elevation-dependent warming; observed changes in snowpack; new future climate scenarios; analysis at the scale of a demonstration site such as Vallter 2000; groundwater and infiltration and their relationship with climate adaptation; and modelling water availability and its relevance to territorial, agricultural and tourism management.

“We need to anticipate change. Understanding how the climate is changing and how it may evolve over the coming decades is essential, but the real challenge is to transform that knowledge into useful tools and criteria for public administrations, managers and territories. The impacts of climate change do not stop at borders, and the response must be built on cross-border cooperation. In just two years, PYRENEES4CLIMA has already been able to provide key data and knowledge for the future of the Pyrenees,” says Eva García-Balaguer, coordinator of the Pyrenean Climate Change Observatory (OPCC). The project began in 2024 and will run until 2031.

A precipitation deficit of close to 15%

“The most significant changes concern temperatures at the end of the century, which could rise by nearly 5°C in summer compared with 1985–2015 under an intermediate-to-high emissions scenario. The changes are stronger at higher than at lower elevations. As regards precipitation, the overall signal is downward on an annual scale and even more pronounced in summer, with an average expected deficit of close to 15%,” explains Jean-Michel Soubeyroux, Deputy Scientific Director for Climatology at Météo-France. These projections are based on Euro-CORDEX CMIP6 — the most recent regional climate projections for Europe, currently being released.

As regards precipitation, the overall trend is downward, although highly irregular on an annual scale, and even more pronounced during summer, with an average expected deficit of close to 15%.

Warming intensifies between 1,500 and 2,200 metres

Future projections are complemented by new data showing how temperature is already changing according to altitude. The first results of a study by the Meteorological Service of Catalonia (Meteocat), based on data from the 2002–2025 period, show an upward trend in both maximum and minimum temperatures across the three elevation bands analysed — below 1,500 metres, between 1,500 and 2,200 metres, and above 2,200 metres — with the increase particularly pronounced in the middle elevation band.

Between 1,500 and 2,200 metres, maximum temperature has increased by 0.77°C per decade, equivalent to 1.8°C over 24 years, while minimum temperature has risen by 0.86°C per decade, amounting to 2.1°C over the same period. The trend is even more pronounced in winter: maximum temperatures have risen by 2.9°C and minimum temperatures by 3.1°C over these 24 years.

“This phenomenon, whereby warming is more intense at certain mountain elevations, has been demonstrated in different mountain ranges, but had not yet been confirmed in the Pyrenees. These first results suggest that it is also occurring here and that the middle elevation band, between 1,500 and 2,000 metres, is the most affected,” explains Pere Esteban, technician at the Meteorological Service of Catalonia.

Snow loss could contribute to this greater warming

Researchers suggest that one of the hypotheses that may help explain this pattern is precisely the retreat of snow cover. The elevation band between 1,500 and 2,200 metres coincides with the area where this snow loss is most evident. Below 1,500 metres, snow is scarcer and more sporadic, while above 2,200 metres a more persistent snow cover continues to remain during winter and may extend into autumn or spring.

“We need to continue analysing all the data we are obtaining, but the fact that a greater increase in temperature is being detected in the middle elevation zone points to an influence from the presence of snow, since this is the altitude range where the retreat of snow cover is most evident,” Esteban adds.

To further investigate this relationship, Meteocat has installed an automatic weather station in Bonabé, at an altitude of 1,700 metres, and has analysed daily data from weather stations in the area for the 2002–2025 period. In addition, as part of PYRENEES4CLIMA, temperature and relative humidity sensors have been installed along two altitudinal transects: Bonabé-Moredo, in the Catalan Pyrenees, and Panticosa-Infiernos, in the Aragonese Pyrenees, the latter by the Pyrenean Institute of Ecology (IPE-CSIC). Positioned approximately every 200 metres, they will provide vertical profiles between 1,500 and 3,000 metres.

The western Pyrenees have lost the most snow

Observed changes in snowpack are another of the project’s key findings. IPE-CSIC has combined direct observations, observation-driven models and a snow viewer developed using satellite imagery.

“We have detected a decline in snowpack that varies in intensity depending on elevation and mountain area, with the western Pyrenees showing the greatest snow loss. The highest elevations of the Pyrenees have also recorded the largest snow losses. We have also observed a significant increase in snow droughts over the 1959–2024 period,” explains Juan Ignacio López Moreno, researcher at the Pyrenean Institute of Ecology (IPE-CSIC). By contrast, the studies carried out do not show major significant changes in extreme snowfall events or rain-on-snow episodes.

Anticipating water availability to improve its management

Temperature, precipitation and snow are directly linked to another of the major challenges addressed by LIFE Pyrenees4Clima: the availability of water resources.

The work on modelling water availability and its relevance to territorial, agricultural and tourism management is being carried out by the Ebro Observatory, the University of Barcelona (UB), the Agrifood Research and Technology Centre of Aragon (CITA), and the Polytechnic University of Catalonia (UPC).

Within the project, three pilot cases related to the hydrological cycle are being developed: two focused on integrating adaptation strategies into irrigation management, and a third aimed at quantifying the impact of climate change and tourism activities on the aquifers of the Arazas River. Another of the most notable cases has focused on generating key knowledge to improve the management of the Vallter 2000 and Pal-Arinsal ski areas in Catalonia and Andorra, respectively.

During the workshop taking place in Vall de Núria, the work relating specifically to the two irrigation cases has been presented.

In Algerri-Balaguer and the Urgell canals, in Catalonia, the models being implemented will be able to estimate water resource availability and irrigation demand using climate scenarios and physical simulation models. They will also help assess the potential for incorporating seasonal forecasts during agricultural campaigns to improve irrigation planning and adaptation.

In La Violada, in Alto Aragón, the models and analysis of current practices will help assess and identify sustainable agricultural practices relating to soil management, crop types and irrigation allocations, as well as their effects on carbon sequestration, greenhouse gas emissions, water requirements and irrigation demand.

The results will be made available to irrigation communities, farmers, river basin managers and other users, with the aim of facilitating their application and transfer to other territories over the coming years.

In this case, LIFE Pyrenees4Clima builds on the results obtained from an earlier project, PIRAGUA, whose findings pointed to an average decrease in river flows of between 10% and 20% during 2011–2040 under the RCP4.5 and RCP8.5 scenarios, and of between 25% and 50% by the end of the century, with the largest decreases under the highest-emissions scenario.

Pyradapt and new synergies for sharing solutions

The workshop will continue on Tuesday with a second session focused particularly on capitalising on, transferring and connecting knowledge generated both within and beyond LIFE Pyrenees4Clima. In this context, the OPCC will present Pyradapt, a tool for capitalising on information, impact and result indicators, and monitoring mechanisms, which is being made available to complementary projects whose objectives include climate change and the Pyrenean territory, with the aim of providing the public with a source of robust, verified and as comprehensive information as possible.

LIFE Pyrenees4Clima, led by the Pyrenean Climate Change Observatory (OPCC), has a budget of €19.8 million, 60% co-financed by the European Union’s LIFE Programme, brings together 47 organisations and is developing 33 pilot and demonstration actions.

The project works from a cross-border perspective to connect science, public administrations, managers and territories, and to transform climate knowledge into adaptation tools, criteria and solutions that can be tested, shared and transferred throughout the Pyrenees. A key instrument for achieving this is the organisation of workshops such as this one, attended by around 90 people from different professional backgrounds — including scientists, public administration officials and territorial managers — with the aim of sharing and transferring knowledge and proposing ways to better address the challenges posed by climate and global change in mountain areas.