Subscribed Content The ChristmasEaster shift: simulating Alpine ski resorts' future development under climate change conditions using the parameter 'optimal ski day'

Ski tourism is strongly influenced by climate change. The economic success of ski tourism regions depends on both the quantity and quality of the ski resorts' opening days. However, to date there has been little research on the quality of ski season opening days. The purpose of this paper is to develop and apply a parameter that enables us to assess the future development of ski seasons in a differentiated way. The results show a decrease of ski area opening days from 2011 to 2060 in the investigation area in general and a trend to an intra-seasonal postponing of optimal ski days, labelled the 'Christmas�Easter shift'. The parameter developed contributes to our understanding of climate change effects on the tourism supply-side at a regional scale and offers decision support to ski lift operators or tourism associations in terms of adaptation measures.