Common sense of snow removal

1. What weather knowledge is there except that it snows and does not cool down?

Dry heat preservation theory: this view holds that when it snows, the air humidity is low and dry, which makes the air and clothes warm, while when it snows, the air humidity is high and the air heat transfer is strong, which makes people feel cold.

In this regard, we say: when it snows, snowflakes fly all over the sky, and when it melts, there is snow and water everywhere. In these two kinds of weather, the relative temperature is very high, and the saturated vapor pressure of ice is the same as that of water at 0oC, so the relative humidity on snowy days and thawing days should be similar. According to Nanchang meteorological statistics, the average relative temperature in snowy days is 8 1.

8%, absolute humidity is 4. Eight millimeters of mercury.

The average relative humidity on snowy days is 83. 6%, absolute humidity is 5.

38 mm Hg. Although the humidity is slightly higher when the snow melts, its influence on the air thermal conductivity is almost zero.

As for the warmth of clothes, there should be little difference. Therefore, this slight humidity change will not produce obvious "snow is not cold" effect.

Although the above statement is reasonable, the basis is still insufficient. Secondly, Hua said, "It is often windy when the snow melts, so it looks very cold." .

According to the meteorological data of Nanchang in recent years, the average wind speed in snowy days is 2. 3 m/s, the average wind speed in snowy days is 1.

1m/s. Therefore, this theoretical basis is insufficient.

Third, radiation heat dissipation said: "In snowy days, the sun usually comes out and there is no support in the air, so the ground heat is easily lost at night, so the lowest temperature in snowy days is lower than that in snowy days." According to Nanchang's statistics, the average temperature on snowy days is -2.

At 76 degrees Celsius, the average temperature on snowy days is -65438 degrees +0 degrees. 8 degrees Celsius.

The lowest temperature is still low in snowy days, so this theory is not valid. Fourth, overcorrection: "Snow is not cold, snow is cold, mainly because the ancients made overcorrection to emphasize that snow is still cold. It's actually colder than snow.

There are many such overcorrections in our country's weather proverbs, such as: "There are eighteen autumn tigers after beginning of autumn." In other words, the weather is still very hot after beginning of autumn.

There is some truth in the above statement, which can be said here for your reference. After reading the above explanation, I don't quite understand.

In this regard, according to the survey results in rural areas, the author puts forward the following new explanations for discussion. First of all, the people who can sum up that "snow is not cold, snow is cold" must be the lower intellectuals and laborers.

Because those dignitaries, horse sedan chairs and leather clothes that come in and out, there is a fire pit at home, and people are always waiting to add or subtract clothes, and they rarely feel cold. According to the traditional education of Confucianism, they should only care about self-cultivation, keeping the family in order, governing the country and leveling the world. Those Confucian "black sheep" think mostly of romantic affairs, so they don't care about the cold and warm in snowy days.

Most of the middle and lower class intellectuals and laborers live in huts and walk on their own when they go out, which makes them realize that "it's not cold when it snows". According to the author's investigation, until the forties and fifties of this century, rural farmers near Nanchang basically lived in straw houses.

Straw is easy to rot when it is wet, so it is not warm. Therefore, farmers living in straw houses have to replace the grass covered on their houses with hay in the year after the autumn harvest. Today, although farmers have lived in tile houses, they still maintain the habits of that year. Every year, the grass in the cowshed should be completely changed before the start of winter.

Asked why, he replied, "If we don't change the grass in winter, the cows will freeze to death." As China has a monsoon climate, it is usually cold and rainy in winter.

Therefore, before and after the first snowfall, the grass replaced in early winter will generally remain dry. Especially in the Huanghuai River Basin, it seldom rains in winter. Even if it rains before snowfall, it should be relatively dry after a period of sun and wind.

So the thatch on the roof should be relatively dry when it snows. However, it is impossible to melt all the snow on the roof on the same day due to the change of daily temperature difference when melting snow. Because of the existence of snow water, snow water accumulates on the roof, so that water has enough time to penetrate into the thatched roof.

Because thatch insulation mainly depends on the stagnant air wrapped in grass, once the air is filled with water, the roof insulation will be greatly reduced. According to the test, the thermal conductivity of water is 60 times that of air. Although the average temperature is lower 1-2OC when it snows than when it melts, as long as the thatch humidity increases 10%, it is enough to make people feel that the indoor temperature is lower when it melts.

Due to human activities such as cooking, there is still a lot of heat generated indoors. In addition, the doors and windows are closed (window paper is needed), so the heat is not easily lost. Even if it's ten degrees below zero outside, the temperature of thatch and contact interface can be around-1oC due to the good thermal insulation effect of snow itself.

Because the thick thatch is soaked in snow water, a lot of heat leaks out, making the indoor temperature close to the outdoor temperature. As a result, the indoor temperature is lower than when it snows heavily. People indoors will naturally feel that "it snows without cooling down." For people who are away from home.

Although rubber has been used abroad for hundreds of years, it was not until the forties and fifties of this century that rubber rain boots "flew into the homes of ordinary people" in China. According to the author's investigation, before the forties, upper-class people wore leather shoes in winter, middle-income people wore cotton shoes, and ordinary people wore cloth shoes, Ma Xie and straw sandals.

It would be nice to add a pair of clogs on rainy and snowy days. And one thing these shoes have in common is that they are not waterproof.

It doesn't matter to the dignitaries, anyway, they go in and out by sedan chair, but for the middle and lower class people, they have to step on waterproof shoes in the snow on snowy days, and as a result, their shoes and socks are soaked by snow water, and their feet are close to 0oC. On snowy days, although the temperature is lower, there is no melting point of ice.

Snow is "dry", so shoes keep warm, but the temperature of feet can be much higher than that of shoes and socks stepping on snow water when melting snow. I believe everyone knows this.

As the saying goes, cold starts from the feet, and cold feet will not only make people feel cold all over, but also make people sick easily. This further magnifies the impression of melting snow and cooling down.

To sum up, Puweixin JD.COM was imported from the United States not long ago. Because ordinary people's roofing materials, shoes and socks are not waterproof, ordinary people will feel colder subjectively in snowy days, whether they go out or at home. Therefore, in the past, the proposition that it is not cold in snowy days was established.

But this does not mean that the temperature in snowy days is higher than that in snowy days. However, the traditional explanation of "snow gives off heat and melting snow absorbs heat" is wrong.

2. How to scientifically clear the body snow after snow?

After the heavy snow, many vehicles were completely covered with thick snow.

Some people think that the snow on the car is not dirty and there is no need to wash the car in time. In fact, this is very unfavorable to vehicles.

The seemingly white snow contains a lot of corrosive substances such as acidity, alkalinity or salts. If it is not removed in time, the snow will erode the car paint and make the external bright glaze lose its luster. In addition, if the snow on the car body is not cleared in time, the weather will turn cold after the snow, and the snow will easily freeze, freezing windows, water spray holes, keyhole and so on.

In order to quickly clear the snow on the windshield, many people started the wiper as soon as they got on the bus. Because of the thick snow, the rubber strip on many wipers was crushed by the snow and finally deformed.

Not only did it fail to clear the snow, but it also damaged the wiper. Therefore, when the snow on the windshield of a vehicle is thick, don't turn on the wiper directly. It is best to use a special snow shovel for automobiles to clear the snow.

If there is no snow shovel, you can use a duster to clear a large area of snow on the roof and doors first, and then carefully clear the snow on the windows, rearview mirrors and door handles with soft plastic sheets or rags, as shown in figure 12-22.

3. Knowledge about snow

The precipitation that falls on the earth's surface in the form of solid in the atmosphere is called atmospheric solid precipitation.

Snow is one of the most extensive, universal and main forms of atmospheric solid precipitation. There are many kinds of atmospheric solid precipitation, including beautiful snowflakes, hail that can cause great harm, and snow graupel and ice particles that we don't often see.

Snowflakes form in the sky. How does water vapor in air movement form snowfall? Is the temperature below zero enough? No, if water vapor wants to crystallize, there must be two conditions to form snowfall: one condition is that water vapor is saturated. The maximum amount of water vapor that air can hold at a certain temperature is called saturated water vapor.

The temperature at which air reaches saturation is called dew point. When saturated air is cooled to a temperature below the dew point, the excess water vapor in the air becomes water droplets or ice crystals.

Because the saturated water vapor content of ice surface is lower than that of water surface, the water vapor saturation required for the growth of ice crystals is lower than that of water droplets. That is to say, water droplets can grow only when the relative humidity (relative humidity refers to the ratio of the actual vapor pressure in air to the saturated vapor pressure of air at the same temperature) is not less than 100%; As for ice crystals, they tend to grow when the relative humidity is less than 100%.

For example, when the temperature is -20℃ and the relative humidity is only 80%, ice crystals can grow. The lower the temperature, the less humidity is needed for the growth of ice crystals.

Therefore, in the high-altitude and low-temperature environment, ice crystals are more likely to be produced than water droplets. Another condition is that there must be condensation nuclei in the air.

Some people have done experiments, if there is no condensation nucleus, the water vapor in the air will only condense into water droplets if it is supersaturated to a relative humidity of more than 500%. But such a large supersaturation phenomenon will not exist in the natural atmosphere.

So without condensation nuclei, it is difficult for us to see rain and snow on the earth. Condensation nuclei are tiny solid particles suspended in the air.

The ideal condensation nuclei are those particles that absorb the most water. Such as sea salt, sulfuric acid, nitrogen and other chemicals.

So we sometimes see clouds in the sky, but there is no snow. In this case, people often use artificial snowfall. Snowflakes that don't condense in the sky all fall from the sky. How can there be non-condensing snowflakes in the sky? 1in the winter of 773, a newspaper in Petersburg, Russia reported a very interesting news.

According to news reports, at a dance, due to the large number of people and the burning of hundreds of candles, the ballroom was hot and stuffy, and the ladies and gentlemen in poor health almost fainted in front of the God of Joy. At this time, a young man jumped on the windowsill and smashed the glass with one punch.

As a result, an unexpected miracle appeared in the ballroom. Beautiful snowflakes danced in the hall with the cold airflow outside the window and fell on the hair and hands of people who were dizzy with heat. Someone rushed out of the ballroom curiously to see if it was snowing outside.

Surprisingly, the sky is dotted with stars and the crescent moon is as silver as water. So, where did the snowflakes in the hall come from? This is really a puzzling question.

Is anyone playing any magic tricks? But no matter how clever a magician is, he can't play with snowflakes in the hall. Later, scientists solved the mystery.

It turns out that the breath of many people in the ballroom is full of water vapor, and the burning of candles has scattered many condensation nuclei. When the cold air outside the window breaks through the window, it forces the saturated water vapor in the hall to condense and crystallize immediately and turn into snowflakes.

So as long as it snows, it will snow in the house. The basic shape of snowflakes is beautiful when it snows, but scientists and artists appreciate the exquisite snowflake patterns.

Glaciologists began to describe the shape of snowflakes in detail more than a hundred years ago. Ding Duoer, the originator of western glaciology, described the snowflakes he saw on Luoza Peak in his classic glaciology works: "These snowflakes ... are all composed of small ice flowers, each of which has six petals, some of which release beautiful little lateral tongues like Su Hua, some are round, some are arrow-shaped, or zigzag, some are complete, and some are lattice-shaped, but they are not beyond.

In China, as early as 100 BC in the era of Emperor Wendi of the Western Han Dynasty, there was a poet named Han Ying who wrote a biography of Han Poetry, which clearly pointed out that "there are six snowflakes everywhere." The basic shape of snowflakes is hexagonal, but there are almost no two identical snowflakes in nature, just as there are no two identical people on earth.

Many scholars have observed thousands of snowflakes with microscopes. These studies finally show that it is impossible to form snowflakes with the same shape and size and partial symmetry in nature. Among these observed snowflakes, even the regularly symmetrical snowflakes are deformed.

Why do snowflakes deform? Because the water vapor content in the atmosphere around snowflakes can't be the same in all directions, as long as there is a slight difference, the side with more water vapor content always grows fast. There are many collectors of snowflake patterns in the world. They collect all kinds of snowflake photos like stamp collectors.

An American named Bentley took nearly 6,000 photos in his life. Soviet photographer Siger Mountain is also a photographer of snowflake photos. His charming works are often used as models of structural patterns by artists.

Japanese Nakatani Yoshijiro and his colleagues worked hard for 20 years, shooting and studying thousands of snowflakes in the cold room of the laboratory of Hokkaido University in Japan and in the tent on the snowfield in northern Japan. However, although snowflakes have various shapes, they remain unchanged, so scientists may classify them into the above seven shapes.

Among these seven shapes, hexagonal snowflake and hexagonal prism snowflake are the most basic forms of snowflake, and the other five are only the development, transformation or combination of these two basic forms. The influence of snow on human health In winter, it snows heavily and endlessly.

People often ignore the role of snow when watching Yushu Qionghua. Snow has many benefits to human health.

Compendium of Materia Medica has long recorded that snow water can detoxify and cure the plague. Folk use snow water to treat burns.

4. How to quickly clear the snow of vehicles in snowy days in winter?

When using a car in winter, you should pay attention to the tips of removing snow and saving fuel. When there is snow on the front windshield, the wiper cannot be started immediately. The weather is getting colder and colder, and it seems that it is getting closer and closer to snow.

So, what's your trouble with using a car on snowy days? Many car owners report that the biggest worry in rainy and snowy days is not to drive, but to park the car outdoors and clear the snow on the car glass before driving. As long as the driving speed is slow, there will be no problem, but because of the cold weather, my hands will freeze when removing snow, so it is very troublesome.

Option 1: Snow removal is the most commonly used method for car owners, but there is a lot of knowledge about how to remove snow. Master Wang, who has been driving for many years, told reporters that when there is more snow on the windshield before winter, don't use a wiper to remove snow immediately.

Many car owners will habitually turn on the wiper when they see snow, which will easily damage the wiper, especially in freezing weather. Even if there is no obvious failure of the wiper after snow removal, it is easy to hurt the rubber strip of the wiper.

The correct way is: start the car first, turn on hot air and blow the front window glass; Then use a brush or towel to clear the snow. If there is ice, you can use tools such as ice shovel or plastic scraper to remove the residue.

When the snow is basically cleared and the snow on the windshield melts, the owner can use the wiper normally. When using tools to remove ice and snow, try to move in the same direction, and never scratch back and forth to avoid scratching the glass with hard objects left on it.

In addition, some impatient car owners like to thaw with hot water, which will easily cause the window glass to break and the wiper to deform. Moreover, rapid cooling and rapid heating are also very harmful to the paint surface of the car body, and it is recommended that the owner not use it.

Option 2: Shelter If you think snow removal is too troublesome, you'd better add a coat to your car or the front windshield, so as to keep the snow and ice out of the car. Choose a coat for the car, the first choice is the car clothes.

With the protection of car clothes, no matter how thick the snow is, everything will be fine if you take off your clothes. In addition, the air is dry in winter, especially during the Spring Festival, fireworks and firecrackers will be set off in some places, which is easy to catch fire.

High-quality car clothes have the functions of acid prevention and fire prevention, and are also a kind of protection for your car parked outdoors. Not only in winter, but also in summer, clothes are not wasted.

In hot summer, the car clothes can effectively resist the damage of strong ultraviolet rays to the car paint interior and tires, and can also prevent the temperature inside the car from being too high. However, the choice of clothes is very important. If the car clothes don't fit and are unqualified, it is better to * * *.

The reporter saw in the auto supplies market that some clothes made of PVC are actually a layer of plastic, and some even have no rearview mirror cover. This kind of car clothes is loose when worn on the car body. When the wind blows, the car clothes beat on the car body, but it will scratch the car paint.

A good car coat should be completely suitable for the original car in size. In addition, pay attention to the use of car clothes, and remember to tighten the rope every time you put on "clothes"

Fold the clothes flat after putting them away. Never knead it into a ball at will, so as not to leave many tiny wrinkles on the car clothes. Paint the car next time. In addition, the owner should also pay attention to prevent the car body from getting wet and avoiding freezing with the car clothes.

Snow removal tips try two common methods to deal with the snow on the front windshield. As the saying goes, "the wisdom of the masses is infinite", and car owners also have many tips on snow removal.

Cut the large degradable plastic bag for garbage, and cut a large piece according to the size of the front windshield. After parking the car every day, cover the glass with plastic, clamp it with the left and right front doors on both sides, and press it with a raised wiper in the middle to prevent it from being blown away by the strong wind.

When driving in the morning, just take the plastic off! Sometimes the wiper will freeze when it snows. After parking, put a newspaper or a rag under the wiper and it will be much easier the next morning.

Prepare some unused bank cards in the car. It's snowing, just use the bank card to remove the snow.

Thin enough, enough to make money, not to hurt the glass! I bought a glass cleaning tool when I was decorating, and it has been idle ever since. I had a brainwave that day and took it to the car. I find it very useful to clean the window glass, and snow removal is also first-class when it snows.

The price is only a few dollars, use it all! According to a friend, it is very useful to lay a layer of newspaper on the front windshield after parking in snowy days. This method is very simple, but after repeated experiments, it is found that if the newspaper is wet, it is easy to get on the glass and not easy to remove.

My way is to wipe the water off the glass before spreading the newspaper, and then spread several layers of newspapers, so that the chance of getting wet is reduced. In winter, it is best to park your car with your back to the wind. In the cold winter, the car has become a warm haven when we go out.

How to make the car safe for the winter, we summed up the experience of some old drivers. Necessary items: gloves, dry rags, fire extinguishers. Although many people don't need to wear too thick equipment when driving out, it is also necessary to have a set of winter clothes and a pair of gloves in the car. In case the tire needs to be changed in the snow and ice, these preparations can be like straws.

Dusting the dust and snow off the car with a duster is what every driver will do, but be careful not to wipe the window with a wet cloth, which will freeze the window and make it more beautiful, so it is best to have a dry cloth on the car in winter. It is windy and dry in winter, and some low-quality smokers throw away cigarette butts that have not been extinguished by sparks. In addition, dry branches and dead leaves are easy to enter the engine compartment, so a perfect and effective fire extinguisher is also a necessary item.

Parking position: It is common to choose a sheltered and dry place in winter, which is mainly caused by the large temperature difference between the inside and outside of the car. Therefore, before going home to park at night, open the window for a few minutes to appropriately reduce the temperature inside the car to avoid frosting on the windshield when driving in the morning. If conditions permit, it is best to park the vehicle indoors or in the underground parking lot.

If you can only park outdoors, you should also choose a sunny, sheltered, flat and dry place to park. It is best to turn your back to the wind when parking, which can reduce the damage of ice and snow to the car water tank and engine.

In addition, it is windy in winter, so it is best to park your car in an open place to avoid falling objects and hurting your car. Dealing with icing: stop at night to support the wiper blade. Before and after turning on and off the wiper, pay attention to wipe off the snow, ice and water left on the wiper blade and wipe the windshield to prevent the wiper blade from freezing together. If necessary, stop at night to support the wiper blade to ensure that it will not freeze.

Once the skylight freezes, cut it off.