Snow, the white fluff of the winter landscape, is not only one of the most charming atmospheric phenomena but also a small wonder of nature. Falling from the sky in the form of light ice crystals, snow transforms the environment, giving it a magical aura.
Its presence arouses both the joy of children on sleds and the concern of drivers during snow blizzards. This fascinating atmospheric phenomenon is not only aesthetically significant but also affects life on Earth in a variety of ways. Snow blizzards, frosts, or glaze are associated with precipitation, which affects road conditions and social life.
But if it weren’t for snow, there would be no winter sports, and no adequate supply of water to soul in the spring, not to mention the most wonderful setting for Christmas.
These crystals are mainly shaped like six-pointed stars, combining to form snowflakes. After falling to the ground, the snowflakes form a cover-snow.
These droplets attach themselves to nuclei of crystallization, which can be, for example, dust particles. This process begins only at temperatures below -12 degrees Celsius. The resulting ice crystals, which are less than 0.1 mm in size, sink downward increasing in size. As the size increases, the ice crystals take on different forms. The most common is the shape of six-pointed stars (at temperatures between -1 degrees Celsius and -3 degrees Celsius and between -10 degrees Celsius and -20 degrees Celsius), although there can be other shapes, such as lumps, needles, columns, plates (temperatures below -20 degrees Celsius). It depends on humidity, pressure, and air temperature.
Snow crystals are almost perfectly symmetrical, although most are irregular in many respects. The rule by which the six arms of a crystal assume an identical shape is not known, and at the same time none of the crystals are identical. It is known to be affected by changes in temperature and humidity as the crystals move inside the could. The greatest complexity of snow crystals is observed when humidity is high. When the temperature is low, the ice crystals are smaller, and have a simpler structure and there are fewer of them (the so-called snow grit) - at temperatures below zero, the snow cover is smaller.
If the air temperature is close to freezing, the individual ice crystals stick together with the help of small water droplets and form cotton ball-like snowflakes.
Each crystal is transparent, like ice. Light is reflected and scattered at the interface between the ice crystals and the air. A large number of such ice crystals with a random arrangement relative to each other leads to an overall diffuse reflection, which is why snow appears white.
As temperatures rise, snowflakes become larger as the crystals thaw and then stick together to form large flakes. The largest documented snowflake had a diameter of 38 centimeters - a result that was listed in the Guinness Book of World Records.
This is the view of some researchers, claiming that a snowflake falling on water produces a high-frequency sound of 50 to 200 KHz, which is inaudible to humans (ultrasound). This sound reaches a peak and then quiets down. All this lasts for one ten-thousandth of a second.
This phenomenon was discovered about 15 years ago but was not subjected to research. It was brought to the attention of biologists in Alaska, who used sonar to track salmon migrations. The sound of falling snow drowned out the signals sent by the fish, so they had to stop their observations.
The phenomenon was explained in the New Scientists journal. When a snowflake falls on the water, there are only faint sounds below the surface. But when it begins to melt, there is a suction of water caused by the phenomenon of hairiness. At this time, air bubbles are released from the surface of the snowflake or trapped by the water. The bubbles vibrate, trying to reach a state of equilibrium, and at the same time send out high-frequency sound waves.
On average, heavy rainfall falls at about 20 kilometers per hour, and hail can reach much higher speeds. The speed at which snowflakes fall is largely unaffected by their size, since the area of the flakes increases almost proportionally to their size, the air resistance remains approximately constant.
Snowfall can pull airborne microplastics to the ground.
This was done by German lawyer, astronomer, naturalist, and nature photographer Johann Heinrich Ludwig Flögel. In 1885, American farmer, photographer, and snow researcher Wilson A. Bentley photographed more than 5000 different snow crystals.
The main areas prone to snow are the Artic, Antarctica, the northern hemisphere, and alpine regions.
Snow flurries are minor snowfalls that cause light dusting or no snow accumulation.
During snow showers, the intensity of a snowfall varies and lasts for brief periods. Some amount of snow may accumulate.
Snow squalls lead to, typically, a significant accumulation of snow.
Blowing snow causes serious drifting and visibility reductions.
Blizzards are the most dangerous. They are strong snowstorms characterized by strong winds and poor visibility, lasting for an extended period, usually three to four hours. Blizzards can be enormous and usually extend for hundreds or thousands of kilometers.
It was the deadliest blizzard in history. At the time, 7.9 meters of snow fell, completely covering 200 villages. The snow fell for almost a week and completely covered an area equivalent in size to the state of Wisconsin.
Temperatures there dropped to – 30 degrees Celsius, and up to 180 centimeters of snow fell in most of the country’s mountainous regions, resulting in the deaths of at least 926 people there. More than 100.000 sheep and goats died, as well as nearly 315.000 cattle.
They were observed by the Phoenix probe. The snow fell from clouds flowing four kilometers above the lander and by the time it reached the surface it had passed into a gaseous state (sublimated).
This was known as virga, or precipitation that does not reach the surface because it evaporates or sublimates before it falls. This phenomenon usually occurs when the lower atmosphere has low humidity.
