Snow in the desert: sustainability of the Trojena ski resort in Saudi Arabia

Trojena is a ski resort under construction in the Midian mountains in Saudi Arabia (1500m-2600m). In this warm and arid region, snowfalls are very rare. The average snow cover duration as observed with MODIS is less than 2 days per year during the 2000-2022 period, casting doubts on the possibility to develop a ski resort as advertised by the project managers. Low temperatures at high elevation might allow the production of artificial snow in winter. To examine this possibility, we downscaled  ERA5 meteorological data to 100 m resolution over the Trojena area with MicroMet. We used these high resolution meteorological dataset to  simulate the natural snowpack between 1995 and 2014 at the uppermost and lowermost points (respectively 2389 and 2151 m a.s.l.) in the future ski domain using  the Crocus snowpack model with the default parameters used in France. We evaluated the simulations using Landsat observations of the snow cover. With this model configuration, the snow cover duration with Crocus is slightly overestimated. Then, we ran the Crocus-Resort model  to simulate artificial and managed snow (production of artificial snow and grooming processes) with the default parameters used for French resorts. We evaluated the potential number of skiable days and associated water consumption over this period assuming that the domain was fully equipped to produce artificial snow. In this scenario, the number of skiable days would be approximately 60 and a water consumption around 380 kg.m⁻². Finally, we examined the effect of future climate change by applying the projected temperature increases according to the IPCC scenario SSP2-4.5 on the 2040-2060 horizon. The number of skiable days decreased in this scenario, especially at the bottom of the resort where there would be no skiable days every other year. As a result, the possibility of skiing on snow in Trojena is strongly compromised in the near future. The water consumption decreases in this scenario due to the incapacity of producing snow with the increase of temperature.