In any case, for this type of study, you usually look for a parameter whose future development you are considering, for example "days with enough snow" or "days cold enough for artificial snow production" and then use climate models to consider how the parameter could change. ("How many days with sufficient snow are there with a warming of X degrees at location Y?") The natural sciences usually leave it at that.
However, the paper mentioned above is not satisfied with such trivial things as the amount of snow or temperature, but defines and examines the "optimal ski day" (OSD) in order to make a statement not only about the quantity of possible future ski days, but also about their quality. An OSD is a sunny day without strong winds, with a perceived temperature between -5 and +5° C. All lifts are open and there is at least 30 cm of snow (natural or artificial) on the slopes. The surrounding area is also covered in snow, but it's all about the look, just a few centimetres are enough. An OSD also always falls on a weekend or a public holiday. The idea behind this is that a high number of OSDs can ensure that a ski resort is worthwhile even with fewer operating days, as significantly more visitors come on these days.
The study concludes that the number of OSDs per season will decrease in future, meaning that more money will have to be generated on fewer days. It is also assumed that OSDs will shift from the Christmas vacations towards Easter and therefore recommends other marketing strategies for Christmas tourism (keyword: fog hiking). In general, it is expected that the image of a region will change as a result of climate change. The Allgäu, for example, is an "alpine region" that tourists associate with "green grass and grazing cows". In the future, the landscape there will be characterized by agricultural monocultures, so one should be prepared for this in terms of marketing (fog hiking in a field of genetically modified maize?).
Another study entitled Winter Tourism, Climate Change, and Snowmaking in the Swiss Alps: Tourists' Attitudes and Regional Economic Impacts (Pütz et al 2011, Mountain Research and Development), found that people generally prefer to go on vacation in beautiful areas and don't like ugly ones. In addition, summer tourists tend to dislike artificial snow, while winter tourists find it quite good. (In 1990, winter tourists didn't like snow cannons either.) The study found that there is a significant, positive correlation between "engagement in skiing" and "positive attitude towards artificial snow". Who would have thought it? Anyone with a negative attitude towards artificial snow either doesn't ski or doesn't realize that they often ski on artificial snow anyway.
