Industrieschnee: An overview of some European anthropogenic snowfall events, with a case study from Bern (Switzerland)

Industrieschnee or anthropogenic snowfall is a local winter hazard in many European cities and towns under suitable anticyclonic conditions and in the vicinity of persistent local water vapour sources and air pollution. Here, we overview the formation of Industrieschnee and describe a case study event from Bern, Switzerland, comparing the estimated mass of snow deposited with the water vapour emissions from a local incinerator. We speculate that previous European Industrieschnee events may have been considerably under-reported, or falsely attributed to surface hoar frost (reif) or the accretion of rime (raureif).