How to artificially snow? What is the difference between artificial snow and natural snow?

arson on the ground and a large amount of smoke and dust into the sky; attacking the clouds with artillery; Use the kite to fly high in the clouds, and then electrify the kite, flash and discharge sparks; Fly into the clouds and spray liquid water droplets and dust particles. However, none of these methods worked well. It wasn't until 1946 that it was discovered that millions of snow crystals could be formed when very small particles of dry ice were thrown into cold clouds.

At present, the most effective method is to sprinkle solid CO2 at high altitudes

The differences between artificial snowfall and natural snow are as follows:

Artificial snow, also known as artificial snowmaking, refers to the process of artificially turning water (water vapor) into snowflakes or snowflakes through certain equipment or physical and chemical means. Artificial snow manufacturing methods are divided into cannon barrel type and borneol crushing type.

Natural snowflakes have a density of about 328 kilograms of cubic meters, while artificial snow has a density of about 856 kilograms of cubic meters. Essentially, artificial snow and natural snow are the same, but artificial snow is denser. Therefore, under the same conditions, artificial snow of the same volume melts more slowly than natural snow.

Artificial snow does not go through the long life course of snowflakes and is different from natural snow. Every natural snowflake contains a variety of meteorological information from its formation to its descent to the ground, and it has been said that no two snowflakes in the world are exactly the same. However, the artificial snow is formed and the potatoes are shouted by the hands of the hand, the time is short, the growth is fast, and the shape of the snowflakes is basically the same.

Natural snowfall changes in hardness the next day and is very slippery, making it a great way to slip. However, artificial snow is not only expensive to make, but also has poor snow quality, so it feels different to slip.

In addition, it is important to note that 1 tonne of water can produce 2 cubic metres of snow, and a snow gun uses 16 tonnes of water per hour. After the ice carnival and ski resort artificial snow, the vast majority of it will evaporate or penetrate into the ground through the air, which cannot be reused, which may cause waste. Snowmaking and water extraction from ski resorts can cause a significant loss of groundwater and may also aggravate spring drought in mountainous areas.

Artificial snowmaking may also cause some damage to vegetation.

Rationale

Artificial snowfall must first have clouds in the sky, and without clouds, it is like it is difficult for a clever woman to cook without rice, and it will not snow. Clouds that can snow, "cold clouds" that are below 0. In the cold clouds, there are both small water droplets condensed by water vapor and small snow crystals condensed by water vapor.

But they are all small and light, and if there are no conditions to continue growing, they can only be suspended in the air like smoke and dust, and it is difficult to fall.

In winter, we often see large clouds that do not see snowflakes falling, because the snow crystals that make up these clouds are too small to overcome the buoyancy of the air, and the precipitation capacity is very poor. If some particulate matter is sprayed in the clouds, and the snow crystals grow quickly enough to overcome the buoyancy of the air and fall down, this is artificial snowfall.

The difference between artificial snowfall and natural snowfall is that artificial snowfall is to spray some particulate matter, soot, dry ice, and silver iodide in the clouds through cannonballs, and then use cannons to launch them into the clouds, provided that there must be clouds in the sky, and artificial snow cannot fall without clouds. Natural snowfall is the crystallization of water and dust at low temperatures.

Formation of snowflakesIt is mainly related to water vapor in the air. When the winter temperature drops below 0, the water vapor in the air condenses into Xiaoice crystals in the clouds. Water vapor is formed when ice crystals in clouds collide with supercooled water droplets and evaporate.

As the water vapor condenses, it gradually increases in size and slowly turns into snowflakes. Since snowflakes are formed by the enlargement of ice crystals, and the molecules of ice crystals are mostly hexagonal, snowflakes are also mostly hexagonal.

Snow has a wide range of effects, but snow has great benefits for humans. First of all, it is conducive to the growth and development of crops. Because snow conducts heat very poorly, the soil surface is covered with a layer of snow cover, which can reduce the transfer of soil heat and block the invasion of cold air on the snow surface, so the crops protected by snow can safely overwinter.

Snow also stores water for crops. In addition, snow enhances soil fertility.

The purpose of artificial snowfall is to improve winter and springPrecipitation。Reducing the frost damage loss of overwintering crops, increasing water and soil vigor are conducive to the smooth progress of spring sowing. At the same time, the process of artificial snowfall is conducive to air purification, soil moisture improvement and forest fire danger level.

Winter and spring are the main times for artificial snowfall, and the need for artificial snowfall depends on the local water resources.

Composition of snowflakesIce clouds are made up of tiny ice crystals. When these Xiaoice crystals collide with each other, the surface of the ice crystals will heat up and melt somewhat, and they will stick to each other and freeze again. This is repeated many times, and the ice crystals increase.

In addition, there is also water vapor in the clouds, so the ice crystals can continue to grow by condensation.

However, ice clouds are generally very high and not thick, where there is not much water vapor, and the growth of condensation is very slow, and there are not many opportunities for collisions with each other, so they cannot grow to a large size and form precipitation. Even if precipitation is caused, it tends to evaporate on the way down and rarely reaches the ground.

Silver iodide is now commonly used for artificial snowfall. Silver iodide is a yellow-colored chemical crystal that is commonly used as a photosensitive agent in photographic materials. The crystals of silver iodide are very similar in size to the hexagonal monomers of snow crystals, the atomic arrangements in their monomers are also very similar, and the lattice spacing between the two is also very similar (silver iodide is angstroms, snow crystals are angstroms).

Therefore, by sprinkling silver iodide particles in clouds with poor precipitation ability, so that they can "impersonate" the snow crystals, the water vapor and small water droplets in the clouds can condense and crystallize on the "impostor" crystals and become snowflakes.

Using a cannon, loading chemicals into a cannonball, and then using the cannon to shoot into the clouds. However, this method is unevenly sprayed, and the waste of medicine is large, which increases the cost of artificial snowfall. Others put them in dirt rockets and let them fly into the clouds and spray them.

In general, artificial snowfall has a greater success rate than artificial rainfall. Artificial rainfall can increase rainfall by about 20%, while in alpine and cold regions, artificial snowfall can increase precipitation by 30 to 40%. This is because in alpine and cold regions, where the temperature is low, water vapor tends to reach saturation, and at the same time, snow crystals are more likely to form than raindrops.

Artificial snowfall is a process in which a "catalyst" such as solid carbon dioxide (dry ice) and silver iodide is scattered between the clouds by artificial aircraft, artillery shells, rockets, etc., causing the water vapor to quickly condense into large ice particles and fall, forming snowfall (rainfall). This is different from "artificial snowmaking" when a large amount of water mist is frozen into snowflakes by a refrigeration system. Artificial snowfall is the process of using nature's own water vapor to form snowfall.

The process of turning water (steam) into snowflakes or similar snowflakes by some kind of equipment or physical and chemical means. Artificial snowmaking methods are divided into cylindrical and icebreaker types.

How did "artificial snowfall" come about? After watching the whole process, I finally understood.

The purpose of artificial snowfall is to increase the precipitation in winter and spring, reduce the frost damage loss of overwintering crops, increase water and soil vitality, and facilitate the smooth progress of spring sowing. Commanding ants

At the same time, the process of artificial snowfall is conducive to the burial of sails to purify the air, improve the condition of the soil wall and reduce the forest fire danger level. Winter and spring are the main times for artificial snowfall, and the need for artificial snowfall is determined according to the local water situation. Silver iodide is often used for artificial snowfall.

Silver iodide is a yellow-colored chemical crystal, which is usually used as a photosensitive agent in lighting materials. The hexagonal monomers of silver iodide snow crystals are very similar in size, the atomic arrangement in their monomers is also very similar, and the lattice spacing between the two is also very similar (silver iodide is angstroms, snow crystals are angstroms). Therefore, snowfall missiles are used to scatter silver particles in clouds with poor precipitation ability, making it "impersonated.""Replacing the snow crystal, it can make the water vapor and small water droplets in the cloud condense and crystallize on the "impostor crystal" and turn into snowflakes.