SPASS – new gridded climatological snow datasets for Switzerland: potential and limitations
Year: 2025
Type: article
Abstract: . Gridded information on the past, present and future state of the surface snow cover is an indispensable climate service for any snow-dominated region like the Alps. Here, we present and evaluate the first long-term gridded datasets of modeled daily snow water equivalent and snow depth, which are available for the last 60+ years (since 1962) at 1 km spatial resolution over Switzerland. The comparison against a higher quality, but shorter model dataset shows on the one hand a good performance regarding bias and correlation and on the other hand acceptable absolute and relative errors except for ephemeral snow and for shorter time aggregations like weeks. The comparison against in-situ station data for yearly, monthly and weekly aggregated values at different elevation bands demonstrates only slightly better performance scores for the higher quality dataset, which demonstrates the good performance of the quantile-mapping method which was used to produce the long-term climatological from the higher quality dataset. A trend analysis of yearly mean snow depth from this gridded climatological- and from station-based data revealed a very good agreement on direction and significance at all elevations. However, at the lowest elevations the strength of the decreasing trend in snow depth is clearly overestimated by the gridded datasets. Moreover, a comparison of the trends between individual stations and the corresponding grid points revealed a few cases of larger disagreements in direction and strength of the trend. All these results imply that the performance of the new snow datasets is generally encouraging but can vary at low elevations, at single grid points or for short time windows. Therefore, despite some limitations, the new gridded snow products show promise as they provide high-quality and spatially high-resolution information of snow water equivalent and snow depth, which is of great value for typical climatological products like anomaly maps or elevation dependent long-term trend analysis.
Source: The cryosphere
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Climate action
Open Access status: gold
Estimated APC paid: $1,574
OpenAlex ID: W4415363642