Less snow, which would melt sooner. Rivers whose flow rates would decrease by 15% by the not-so-distant horizon of 2040. And by 20% by the end of the century. This is the worrying prospect drawn for the Pyrenees by an international study unveiled this Tuesday, in the middle of COP28. The Piragua project – a consortium of Spanish, Andorran and CNRS researchers for the French side – notes that the scenario of reducing the massif’s water resources has already begun. This is mainly due to the increase in average annual temperature of +0.8°C between 1981 and 2010. But also because mountain agricultural land tends to disappear in favor of greater forest cover.
“The results of the models show very consistently that in the future the climate of the Pyrenees will be warmer and drier, with a general increase in aridity both in space and in time, except in areas the highest, explains Santiago Beguería, the Spanish scientist leading the Piragua project. In general, there will be a gradual decrease in the annual flows of the Pyrenean rivers, which will become more pronounced as the century progresses. This reduction will be greatest under the most pessimistic emissions scenario.”
We dare not imagine the consequences on skiing and canyoning opportunities.
The idea of involving residents in water management
Scientists see even broader and insist on the fact that the rivers of the Pyrenees have “primary importance” well beyond the massif. They “ensure the water needs of agriculture, industry and the drinking water supply of a vast region extending on both sides of its foothills,” they emphasize.
And among the measures they recommend so that the crystalline rivers of the Pyrenees do not become small streams, there is the original idea of involving the main stakeholders and the best informed in the reflection and management of the resource: the residents.