Have snow depths changed in South Tyrol?
Over the last 40 years snow depth has decreased at most sites in South Tyrol, but differences depending on month, elevation, and location have been recorded. For the 28 locations with more or less complete records from 1981 to 2020, decreases were observed in winter (December to March) at an altitude mainly below 1500m, while above that mark, increases and decreases were equally distributed. Moreover, there were spatial gradients, negative trends were observed mostly in the north and east, while positive trends were observed in the south and west. For example, in the western part of the province, Slingia/Schlinig, situated at an altitude of 1690m, had a mean snow depth for February which increased from 48cm to 63cm, while at 1860m, Diga di Neves/Neves Stausee, in the north-east, the snow depth decreased from 86cm to 66cm. At the end of the season, that is April to May depending on elevation, no positive trends were observed. In fact, in most locations snow has been disappearing on average in the last month of the snow season. Today, April is on average snow-free below 1500m, while 40 years ago, 7 to 24cm of snow was not unusual, such as in Sesto/Sexten or Pennes/Pens. The main limitation of these results is that they are restricted to locations below 2000m, because above that altitude, no long-term observation records exist in South Tyrol.