Global reduction of snow cover in ski areas under climate change

S3 Table. Annual snow cover days (mean, median, 5% and 95% confidence interval) per time period and in seven major mountain skiing areas under a low (SSP1-2.6) emissions scenario. (PDF) S4 Table. Mean and statistic differences between historical (1981–2011), present (2011– 2040) and future (I: 2041–2070, II: 2071–2100) annual snow cover days in seven major ski- ing regions worldwide based on a Kruskal-Wallis-Test and a Pairwise Wilcoxon test with Bonferroni correction (alpha = 0.05) for very high, high and low emissions scenarios. Sig- nificant relationships (α = 0.05) are indicated in bold letters. (PDF) S5 Table. Percent change in annual snow cover days between a historic base line (1981– 2011), the present (2011–2040) and the future (I: 2041–2070, II: 2071–2100) in seven major skiing regions worldwide. Confidence intervals are given (CI 5;95). Data for very high, high and low emissions scenarios is given. (PDF) S1 Fig. Violin plots of historical (1981–2011), present (2011–2040) and future (2041–2070; 2071–2100) annual snow cover days in seven major skiing regions worldwide under a very high emissions scenario (SSP5-8.5 scenario). The median and the 5%;95% confidence inter- vals are indicated by black lines. Letters above the violin plots indicate significant differences between groups (Kruskal-Wallis test, Pairwise Wilcoxon test with Bonferroni correction, e.g. a differs significantly from b, c, and d). (TIF) S2 Fig. Violin plots of historical (1981–2011), present (2011–2040) and future (2041–2070;

2071–2100) annual snow cover days in seven major skiing regions worldwide under a low emissions scenario (SSP1-2.6). The median and the 5%;95% confidence intervals are indi- cated by black lines. Letters above the violin plots indicate significant differences between groups (Kruskal-Wallis test, Pairwise Wilcoxon test with Bonferroni correction, e.g. a differs significantly from b, c, and d). (TIF) S3 Fig. European Alps with ski areas and an underlying elevation layer (grey). Colouring indicates the percent change in annual snow cover days in each ski area in the future 2071– 2100 compared to historical (1981–2010) snow cover days under very high emissions (SSP5- 8.5) scenario. (TIF) S4 Fig. Andes with ski areas and an underlying elevation layer (grey). Colouring indicates the percent change in annual snow cover days in each ski area in the future 2071–2100 com- pared to historical (1981–2010) snow cover days under very high emissions (SSP5-8.5) sce- nario. (TIF) S5 Fig. Appalachian Mountains with ski areas and an underlying elevation layer (grey). Colouring indicates the percent change in annual snow cover days in each ski area in the future 2071–2100 compared to historical (1981–2010) snow cover days under very high emis- sions (SSP5-8.5) scenario. (TIF) PLOS ONE Global reduction of snow cover in ski areas under climate change PLOS ONE | https://doi.org/10.1371/journal.pone.0299735 March 13, 2024 10 / 15