Decades ago Norwegians could observe grey, blackish snow at even intervals. But after the heavy industry in Europe cleaned up its act, the snow falling in Norway is for the most part as it should be - namely white. But last week, a string of incidents resulted in heavily polluted snowfall in eastern Norway.
Black snow in Norway - greetings from Europe
Worried citizens in eastern Norway began calling local radio-stations Tuesday 17th of January. The reason? They were observing the fresh snow-fall. Nothing unusual about snowfall in Norway this time of year. But grey or black snow is not a familiar item in the long Norwegian winter.
An enduring high pressure over eastern Europe made the atmosphere accumulate combustion particle emissions from factories in Poland and other countries in the region. The heavily polluted air was then transported through the atmosphere over eastern Norway, where snowfall cleaned the air and brought the pollution to the ground.