Eisblumen-Gardine

Ice flower curtain ... from night frost. These frost flowers have grown outside the window! Frost flowers can also appear on the outside of the double glazing. If the room is not heated or only slightly heated...
If outside air at temperatures above zero degrees passes over surfaces that were previously cooled below freezing, the formations on the outside are created, for example overnight on cars when the weather changes. (u.a. WiKi)

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