The symbol of the Russian winter is not only severe frosts and sparkling white snowdrifts, but also bizarre ice patterns on the window, which, according to an old belief, are drawn by Father Frost himself. Ice crystals are folded on icy glass into unique pictures, in which you can see a fabulous thicket, the depths of the sea, a scattering of stars or fantastic animals.
On frosty days, stunning ice patterns appear on the windows in the form of extraordinary stars, bizarre curls, fabulous trees and flowers. For ice gardens to bloom on the windows, it is necessary that the air in the room is humid, and outside the window there is a sub-zero temperature.
Why do frosty patterns appear on the window
Everyone remembers the parable that Santa Claus draws frosty patterns on the window. He quietly sneaks up to the window at night and draws unique frosty pictures on it with a thin ice brush. In fact, everything is much more prosaic. If the air in the room is humid, and outside the temperature is from zero degrees Celsius and below, then excess moisture condenses on the cold surface of the window glass. Here, the water vapor is cooled and goes from a vapor state to a solid, forming fine crystals.
How ice crystals form
Any glass that looks perfect has microscopic notches and scratches. The moisture that settles on the surface of the glass crystallizes first of all on these smallest defects, and only then new and new ones cling to the first crystals, forming patterns. Sometimes, for the appearance of ice patterns, there are enough dust particles that dot the surface of the glass, or stains that remain after washing the windows. Drafts and air currents also contribute to the appearance of patterns. By the way they are formed, frosty patterns are divided into two types: dendrites, which are branched patterns that resemble trees, and trichites, which are more like stars.
Tree patterns dendrites
Dendrites form at the bottom of the glass, where the water layer is thicker. Here wide trunks of frosty patterns appear, on which thinner branches gradually grow. Dendrites in the lower part of the glass are wide and thick, and in the upper part they are narrower and thinner. Such a frosty pattern resembles a thicket of an impenetrable fairy forest.
Star-shaped trichite patterns
If there are a lot of jags, dust particles and scratches on the glass, then trichites appear on it - frosty patterns that look like stars. First, the epicenter of the pattern freezes - a speck of dust or a notch, and then other crystals join it like rays. As a result, frosty patterns become like a cluster of snowflakes or a scattering of stars. When the temperature outside the window decreases, trichites form dense ice filaments.
When patterns do not appear on windows
If the air humidity in the room is low, and the window has good thermal insulation, then condensation does not form on the glass and frost patterns do not appear. That is why the ice paintings, so familiar to residents of houses with old wooden windows, do not spoil the appearance of residents of apartments with high-quality plastic windows.
