Different temperature responses of mountain rockwalls, soils, and lakes to summer heat waves

Publié le 03/02/2026, cet article étudie l’impact des vagues de chaleur estivales sur les microclimats de montagne dans les Alpes françaises, en comparant la réponse thermique de trois compartiments : parois rocheuses, sols et lacs. À partir de données couvrant un large gradient altitudinal et latitudinal, incluant les vagues de chaleur de 2015 et 2022, l’étude montre que ces événements extrêmes provoquent des anomalies thermiques marquées dans tous les compartiments. Les lacs ont tendance à amplifier le signal atmosphérique, tandis que les sols et les parois rocheuses jouent plutôt un rôle tampon, bien que cette capacité de régulation diminue lors des vagues de chaleur. Les résultats soulignent l’importance d’un suivi à long terme des conditions microthermiques pour mieux comprendre la réponse des écosystèmes de montagne aux événements climatiques extrêmes.

Abstract 

Mountain ecosystems are highly sensitive to climate variations. At fine spatial scales, high-elevation microclimates play a critical role in shaping biodiversity, hydrological processes, and ecosystem services, while also influencing the occurrence of natural hazards such as landslides, avalanches, and floods. Heat waves, which have been increasing in frequency and intensity due to global climate change, present significant challenges to these vulnerable environments. This study examines the impacts of summer heat waves on mountain microthermal conditions in three compartments: rockwalls, soils, and lakes. We assembled data across a latitudinal and elevational gradient in the French Alps including years of two recent heat wave events (2015 and 2022). We calculated thermal indicators to evaluate the buffering or amplifying effects of the atmospheric signal on the investigated
compartments. The average summer temperature and the growing/thawing degree days were more responsive to heat waves than the phenological indicator (e.g., spring mixing date in lakes) and maximum temperature. We found significant anomalies for both the 2015 and 2022 heat waves across almost all compartments and indicators. Lakes tended to amplify atmospheric temperatures (especially in 2022) whereas rockwalls and soils tended to buffer them. However, residues from the relationship between compartment and atmospheric temperatures were large during heat waves, suggesting that these events may reduce the compartments’ buffering capacity. Our study underscores the importance of long-term monitoring of microthermal conditions to provide a more integrative assessment of mountain ecosystem response to extreme meteorological events.

https://link.springer.com/article/10.1007/s10113-025-02517-3?utm_source=...