Snow cover duration at lakes in the Pyrenees

In the framework of the Pyrenees Climate Change Observatory (OPCC) the Cesbio is contributing to the analysis of the snow cover using satellite imagery. In 2016 four projects associated with the Observatory (Climpy, Replim, Canopee y Florapyr) have been programmed with European Regional Development Funds for transborder cooperation on adaptation to climate change for the next three years [1].

 The map below shows a selection of lakes which are being studied as part of the Replim project. If you click on one of the icon, you will see a table which indicates the average snow cover duration (in days) at this location. For example, the field « Year » is the mean number of snow days per hydrological year (01-Sep to 31-Aug) that was observed between 01-Sep-2000 and 31-Aug-2015. The field « Jan » is the mean number of snow days in January over the same period, etc. I made this map using a daily snow cover climatology for the Pyrenees from satellite observations (MODIS snow products, see Gascoin et al. 2015)

See full screen

You can download the data by expanding the left bar and click on « embed and share this map » then scroll down to « download ». The duration of the snow cover depends on various factors, one of the most important being the elevation. We can check this using the SRTM digital elevation model. Here I resampled the DEM from 90 m to 500 m to match the resolution of the MODIS snow maps.

Map of the mean annual snow cover duration at lakes in the Pyrenees

We can now plot the snow cover duration at each lake against the elevation of the corresponding MODIS pixel.

Mean annual snow cover duration vs. elevation at the location of the Replim lakes

There are many lakes above 2000 m in this dataset. These lakes are important proxies of environmental changes, including climate change, in high elevation regions [3].

Notes

[1] European Funds for the 5 the Pyrenees Observatory

[2] The data are available in Zenodo: Gascoin, Simon. (2016). Cloud-free snow cover area in the Pyrenees from MODIS [Data set]. http://doi.org/10.5281/zenodo.162299

[3] Adrian, Rita, et al. « Lakes as sentinels of climate change. » Limnology and oceanography 54.6 (2009): 2283.

Plus d'actualités

The missing link to valorize CESBIO’s applicative research works

=>  My colleagues at CESBIO are extremely creative! Over the past ten years, they have developed a wide range of new products and methods for extracting information from Copernicus data. They don’t just develop and validate the method on a few sites; they continue their work until they have produced data for the whole of […]

Le chaînon manquant dans la valorisation des travaux de recherche en télédétection

=> Mes collègues du CESBIO sont très créatifs ! Ils ont mis au point, au cours des dix dernières années, un grand nombre de nouveaux produits et de méthodes d’extraction de l’information à partir des données Copernicus (Sentinel-1 et 2). Et bien souvent, ils ne s’arrêtent pas à la mise au point de la méthode […]

Sentinel-2 overtakes Landsat in scientific litterature

OpenAlex is a new, yet already very useful, open database for exploring scientific literature. For an upcoming blog post on the CNES Datacampus website, I analysed the proportion of papers that used only one of the Sentinel-2 or Landsat missions, as well as those that used both, in 2025. What struck me was that Sentinel-2 […]

Rechercher