Tiny ice crystals of intricate unique shapes that every winter generously presents to us - this is what snowflakes are. The mystery of this amazing miracle of nature has long attracted inquiring minds. How this phenomenon arises, what laws obey the strict harmony of their forms, and why they are so diverse - this article will try to answer these questions.
The history of the study of snowflakes
Scientists have long tried to find out what snowflakes are, to give an explanation of the complex and harmonious structure of their structure. Their very first drawings from nature were made by the Swiss explorer Mangus in 1555.
At the beginning of the XVII century, the German scientist Johannes Kepler found out that almost all snowflakes are hexagonal crystals. He published a scientific work on this subject.
In the years 1635-1637, the question of what snowflakes were was of interest to the French mathematician Rene Descartes. He described them like lilies, roses and six-pronged wheels. He published his own sketches, on which you can even see snowflakes with eight or twelve cloves, which are very rare in nature.
In 1885, the American scientist Wilson Bentley first photographed a snow crystal under a microscope. For almost fifty years, his collection has amounted to about 5000 such photographs.
Japanese Nakaya Ukichiro, a physicist, was seriously studying how snowflakes form and why they are all so different in the 30s of the twentieth century. He compiled their first scientific classification, and also invented a mechanism for making artificial snow. The name of this scientist is called the Snow and Ice Museum, located in Japan on the island of Hokkaido.
In 1955, the Russian A. Zamorsky divided the snowflakes into nine classes, as well as 48 species. Among them - "hedgehogs", "needles", "plates", "columns", "cufflinks" and others.
American Kenneth Liebrecht, who lives in our days, compiled a "Complete Snowflake Handbook." In his laboratory, snow crystals are grown artificially, it is even possible to give them a designer form.
How snowflakes form
Snowflakes are formed from water vapor. Tiny droplets condense high in the clouds at low temperature and humidity. They encounter dust particles floating in the air and join them. Thus, what snowflakes are made of are dust particles (crystal nuclei) and small ice particles that gradually grow around each of them.
As the future snowflake descends to the ground, more and more ice crystals join it, while its distinctly hexagonal shape is retained. Convex sections of the crystal grow faster.
Faced with supercooled droplets on its way, the snowflake continues to grow. Having reached a critical mass, it falls down - to the ground.
Variety of snowflakes
Countless factors influence how snowflakes form and how they grow. The most significant of them is the alternation of air temperature in different layers of the atmosphere, which the snow crystals have passed.
Snowflakes are constantly changing in the air. In cold zones, the growth of crystals accelerates, they grow significantly in length. Where warmer air reigns, their "rays" practically do not extend, but they begin to grow in breadth. Knowing what snowflakes are, you can easily explain why, depending on weather conditions in a particular area, the typical type of snow usually falls out.
So, in the Baltic states and the central part of Russia in calm weather, snow often falls in the form of large “fluffy” flakes having a complex branched shape. With strong gusts of wind and low temperature, snowflakes collide with each other, crumble and fall down in the form of small fragments. If forty-degree cold weather strikes, the nascent ice crystals will cover the earth with "diamond dust." And in the center of Yakutia, in frosty weather, thin “needles” often fall out of ice.
When it snows
Snow forms when the air temperature is below two degrees Celsius. The opinion that for this the thermometer should certainly fall below zero is a myth. In this case, snow that has already fallen begins to thaw. However, in the process of this, the air temperature in the places where precipitation is located will certainly decrease.
The heaviest snow flakes fall in the range from zero to two degrees. But if the temperature starts to rise above, then what snowflakes consist of - small crystals of ice will melt inexorably. In this case, most likely, you should wait for the precipitation of wet snow, or even rain.