Because the fortress of the Alps stands in the path of atmospheric depressions and air masses, it exerts a decisive influence on Europe's climate. Understanding the meteorological workings of this mineral theater of spectacular phenomena is therefore an essential challenge for scientists seeking to unlock its secrets. And it's a matter of urgency: in mountain areas, climate change is multiplying the challenges and increasing the danger for the population. In the mountains, temperatures are rising twice as fast as on the plains, and cold spells are becoming shorter and shorter. As a result, glaciers are melting, leading to avalanches and landslides that can destroy entire valleys.