Characteristic seasonal changes in nature occur every three months - in spring, summer, autumn and winter. In our country, every year from December to February, it snows heavily - one of the signs of the onset of winter. Does anyone know what snow is? And what is this natural phenomenon in general? Find out in this article!
What is snow
Snow is a peculiar form of precipitation, which consists of small crystals of ice. Scientists attribute it to surface sediments falling directly onto the ground. In addition, snow is one of the indispensable signs of winter coming to a particular region of the globe.
Constancy and inconstancy of snow
Speaking about what snow can be, one cannot but mention its constancy. A common phenomenon is low air temperatures in the absence of snow. In principle, this is the norm when it comes to the so-called climatic winter, characterized by the constant presence of snow on the ground, which lies throughout the calendar winter period.
Oddly enough, but the constancy of snow is a variable value. At least in some parts of the world. It is curious that the inhabitants of some warm regions (Africa, the Arabian Peninsula, Madagascar, South America) of the planet do not know what snow can be. And all because such a weather phenomenon in warm spots of the globe is simply absent or observed once every 10-20 years.
Snow conditions
This is an amazing, but seasonal phenomenon of nature can exist only if there are two conditions:
- a huge amount of moisture;
- low air temperatures (below 0 degrees Celsius).
Weather forecasters have noticed that the most heavy snowfalls occur in nature at relatively high temperatures: from -9 degrees Celsius and above. They explain this by saying that the higher the air temperature, the more water vapor is contained in it. Water vapor is essentially the "foundation" of snow.
For people interested in what kind of snow it is, we note that the range of water content in it is quite large: if you translate these values into numbers, you get from 0.1 to 5 centimeters of water in a 10-centimeter layer of snow cover lying on the ground. Crucial here is wind speed, crystalline structure of snow, air temperature, etc.
What is the structure of snow
The main component of snow is, of course, a snowflake. Despite its meager sizes (on average about 4 millimeters), the snowflake has an unusually perfect symmetry. But researchers are not surprised by this, but by a completely different one! They are amazed not at what kind of snow happens in their structure, but about what kind of bizarre shapes and various patterns form the interweaving of snowflake faces.
If we consider snowflakes from this point of view, then we can safely say that they are all unique. This is a kind of little miracle of the world! It has already been scientifically proven that these snowy "bricks" have extremely clear geometric lines from which a hexagon is formed. The bizarre shape of snowflakes is affected by the level of humidity and, of course, the temperature of the surrounding air.
To make a perfectly smooth snowflake, the water molecules must freeze and turn into an ice crystal. Being in close proximity to each other, they are captured, as if by a chain, and freeze according to a single principle, turning into a geometric figure. Currently, scientists have no doubt that the snowflake is a collection of frozen water molecules lined up in a chain.
Why do you need snow
Snow has several basic properties that have a positive effect on the environment. Let's consider them in more detail.
- Snow absorbs sounds and reduces the impact of various external noises on the surrounding landscape. This happens because there are air bubbles between the snowflakes that weaken the external vibration. By the way, this explains the peculiar crunch of snow during walks in frosty weather. Creak emit frozen crystals, rubbing against each other when squeezed. From this, they are deformed and split.
- What color is snow? In general, by nature it has an exclusively white color. This helps him reflect sunlight, lowering the surrounding air temperature. But why lower it? In order for winter to be winter, not a thaw! In most regions of the globe, winter is unthinkable without snow and low temperatures.
- Another very important role of snow in natural life is a kind of protection of flora and fauna from external harsh conditions. The fact is that the snow cover retains the warmth of the earth accumulated over the whole summer, preventing small animals and many plants from dying, even in crackling frosts. If you recall what the snow happens (we talked about this above), it is easy to guess that it creates a certain supply of moisture, which is necessary for organisms during spring awakening.