The nine interior ski resorts, Sun Peaks, Silver Star, Big White, Revelstoke,

Red Mountain, Whitewater, Panorama, Sunshine Banff, and Fernie were analyzed to see the effect of El Niño-La Niña events on three climate variables important to maintaining favorable ski runs: winter mean temperature, winter snowfall, and winter rainfall. The data for this analysis comes from ClimateBC for the year 1951 to 2025. Because all three of these variables have seen change over this period due to human-caused climate change, each observation was adjusted by subtracting the linear trend (Ycalculated) from the recorded value (Residual = Ycalculated - Yobserved). If Ycalculated = Yobserved, the residual value would equal zero.

            Figure 1 shows vertical dot plots for Sun Peaks ski resort for winter mean temperature, snowfall, and rainfall. Data has been sorted according to whether the observation occurred during either an El Niño and La Niña event, or neutral conditions. The purple lines are the means and the green bars the 10th to 90th percentile intervals. Winter mean temperatures were on average for El Niño years 2.41 and 2.03°C warmer than the averages for neutral and La Niña events, respectively. El Niño winter snowfalls were on average 53 and 63 mm less than the averages for neutral and La Niña events, respectively. Winter rainfalls were on average for El Niño years 27 and 25 mm greater than the averages for neutral and La Niña events, respectively. 

            Figure 2 shows vertical dot plots for Silver Star ski resort for winter mean temperature, snowfall, and rainfall. Winter mean temperatures were on average for El Niño years 2.01 and 1.62°C warmer than the averages for neutral and La Niña events, respectively. El Niño winter snowfalls were on average 47 and 53 mm less than the averages for neutral and La Niña events, respectively. Winter rainfalls were on average for El Niño years 27 and 24 mm greater than the averages for neutral and La Niña events, respectively. 

            Figure 3 shows vertical dot plots for Big White ski resort for winter mean temperature, snowfall, and rainfall. Winter mean temperatures were on average for El Niño years 1.77 and 1.47°C warmer than the averages for neutral and La Niña events, respectively. El Niño winter snowfalls were on average 29 and 47 mm less than the averages for neutral and La Niña events, respectively. Winter rainfalls were on average for El Niño years 21 and 18 mm greater than the averages for neutral and La Niña events, respectively. 

            Figure 4 shows vertical dot plots for Revelstoke ski resort for winter mean temperature, snowfall, and rainfall. Winter mean temperatures were on average for El Niño years 1.91 and 1.52°C warmer than the averages for neutral and La Niña events, respectively. El Niño winter snowfalls were on average 97 and 107 mm less than the averages for neutral and La Niña events, respectively. Winter rainfalls were on average for El Niño years 37 and 32 mm greater than the averages for neutral and La Niña events, respectively. 

            Figure 5 shows vertical dot plots for Red Mountain ski resort for winter mean temperature, snowfall, and rainfall. Winter mean temperatures were on average for El Niño years 1.60 and 1.38°C warmer than the averages for neutral and La Niña events, respectively. El Niño winter snowfalls were on average 37 and 53 mm less than the averages for neutral and La Niña events, respectively. Winter rainfalls were on average for El Niño years 36 and 33 mm greater than the averages for neutral and La Niña events, respectively. 

            Figure 6 shows vertical dot plots for Whitewater ski resort for winter mean temperature, snowfall, and rainfall. Winter mean temperatures were on average for El Niño years 1.52 and 1.26°C warmer than the averages for neutral and La Niña events, respectively. El Niño winter snowfalls were on average 87 and 126 mm less than the averages for neutral and La Niña events, respectively. Winter rainfalls were on average for El Niño years 30 and 27 mm greater than the averages for neutral and La Niña events, respectively. 

            Figure 7 shows vertical dot plots for Panorama ski resort for winter mean temperature, snowfall, and rainfall. Winter mean temperatures were on average for El Niño years 1.93 and 1.55°C warmer than the averages for neutral and La Niña events, respectively. El Niño winter snowfalls were on average 41 and 57 mm less than the averages for neutral and La Niña events, respectively. Winter rainfalls were on average for El Niño years 5 and 5 mm greater than the averages for neutral and La Niña events, respectively. 

            Figure 8 shows vertical dot plots for Sunshine Banff ski resort for winter mean temperature, snowfall, and rainfall. Winter mean temperatures were on average for El Niño years 2.03 and 1.79°C warmer than the averages for neutral and La Niña events, respectively. El Niño winter snowfalls were on average 75 and 89 mm less than the averages for neutral and La Niña events, respectively. Winter rainfalls were on average for El Niño years 4 and 6 mm greater than the averages for neutral and La Niña events, respectively. 

            Figure 9 shows vertical dot plots for Fernie ski resort for winter mean temperature, snowfall, and rainfall. Winter mean temperatures were on average for El Niño years 1.97 and 1.59°C warmer than the averages for neutral and La Niña events, respectively. El Niño winter snowfalls were on average 94 and 93 mm less than the averages for neutral and La Niña events, respectively. Winter rainfalls were on average for El Niño years 14 and 15 mm greater than the averages for neutral and La Niña events, respectively. 

Figure 1 Vertical dot plot for Sun Peaks ski resort for winter mean temperature, snowfall, and rainfall. The purple lines are the means and the green bars the 10th to 90th percentile intervals. One-way ANOVA determined that significant differences exist between the three means (El Niño, La Niña, and neutral) for winter mean temperature and rainfall at P < 0.001. Winter snowfall was considered significant at P = 0.021.

Figure 2 Vertical dot plot for Silver Star ski resort for winter mean temperature, snowfall, and rainfall. The purple lines are the means and the green bars the 10th to 90th percentile intervals. One-way ANOVA determined that significant differences exist between the three means (El Niño, La Niña, and neutral) for winter mean temperature at P < 0.001. Winter snowfall was considered not significant at P = 0.090. Winter rainfall was considered significant at P = 0.002.

Figure 3 Vertical dot plot for Big White ski resort for winter mean temperature, snowfall, and rainfall. The purple lines are the means and the green bars the 10th to 90th percentile intervals. One-way ANOVA determined that significant differences exist between the three means (El Niño, La Niña, and neutral) for winter mean temperature at P < 0.001. Winter snowfall was considered not significant at P = 0.186. Winter rainfall was considered significant at P = 0.005.

Figure 4 Vertical dot plot for Revelstoke ski resort for winter mean temperature, snowfall, and rainfall. The purple lines are the means and the green bars the 10th to 90th percentile intervals. One-way ANOVA determined that significant differences exist between the three means (El Niño, La Niña, and neutral) for winter mean temperature at P < 0.001. Winter snowfall was considered significant at P = 0.010. Winter rainfall was considered not significant at P = 0.061.

Figure 5 Vertical dot plot for Red Mountain ski resort for winter mean temperature, snowfall, and rainfall. The purple lines are the means and the green bars the 10th to 90th percentile intervals. One-way ANOVA determined that significant differences exist between the three means (El Niño, La Niña, and neutral) for winter mean temperature at P < 0.001. Winter snowfall was considered not significant at P = 0.070. Winter rainfall was considered significant at P = 0.007.

Figure 6 Vertical dot plot for Whitewater ski resort for winter mean temperature, snowfall, and rainfall. The purple lines are the means and the green bars the 10th to 90th percentile intervals. One-way ANOVA determined that significant differences exist between the three means (El Niño, La Niña, and neutral) for winter mean temperature at P < 0.001. Winter snowfall was considered significant at P = 0.026. Winter rainfall was considered not significant at P = 0.113.

Figure 7 Vertical dot plot for Panorama ski resort for winter mean temperature, snowfall, and rainfall. The purple lines are the means and the green bars the 10th to 90th percentile intervals. One-way ANOVA determined that significant differences exist between the three means (El Niño, La Niña, and neutral) for winter mean temperature at P < 0.001. Winter snowfall was considered significant at P = 0.005. Winter rainfall was considered not significant at P = 0.279.

Figure 8 Vertical dot plot for Sunshine Banff ski resort for winter mean temperature, snowfall, and rainfall. The purple lines are the means and the green bars the 10th to 90th percentile intervals. One-way ANOVA determined that significant differences exist between the three means (El Niño, La Niña, and neutral) for winter mean temperature at P < 0.001. Winter snowfall was considered significant at P = 0.003. Winter rainfall was considered not significant at P = 0.172.