Soil temperature data for the French Alps

Unlike air temperatures, subsurface soil temperature measurements enable us to truly characterize the thermal conditions perceived by living organisms, primarily the root systems of perennial plants. These measurements are integrated into a number of research projects and observation systems aimed at gaining a better understanding of the links between microclimate, species distribution and ecosystem functioning. These data sets are produced by research units (CNRS, Université Savoie Mont-Blanc, Université Grenoble Alpes, Université Clermont Auvergne) and public establishments (Parc national de la Vanoise, Parc national des Ecrins, Parc national du Mercantour, CBNA).

TheZone Atelier Alpes has funded a project to bring together these different dataset holders in order to standardize measurement protocols, data and metadata, and enable the publication of a collective dataset. This dataset is open-ended, with the possibility of adding new measurement sites, as well as supplementing it with new data on an annual basis. The data collected are time series spanning several years, recorded at hourly time steps using miniaturized, low-cost autonomous loggers. This lightweight instrumentation enables a comparative approach that is quite unique on the scale of the Alps. It is now possible to characterize the thermal regime of mountain soils along climatic, topographical and vegetation gradients. These empirical, local data are important for calibrating and validating microclimatic models and calculating bioclimatic indicators (snow clearance dates, degree-day accumulation, etc.), whether these relate to past simulations (re-analyses) or future climate projections.