Skiers speed down a ski slope with artificial snow in the middle of a snowless field, at 1600 meters above sea level, in the alpine resort of Villars-sur-Ollon, Switzerland, Saturday, Dec. 31, 2022. Sparse snowfall and unseasonably warm weather in much of Europe is allowing green grass to blanket many mountaintops across the region where snow might normally be. It has caused headaches for ski slope operators and aficionados of Alpine white this time of year. (Laurent Gillieron/Keystone via AP)