Why do icicles form? Why do icicles appear? How to make an icicle? Large and small icicles.

The article talks about why icicles appear, how to make them yourself, and what their danger lies in a big city.

Cold

On our planet there are many climatic zones. There are both hot regions and those where summer never occurs, and human life is almost impossible. In some places it almost always rains, while in others it rains very rarely, and it is difficult for their residents to imagine frequent thunderstorms, much less water in its non-liquid state - snow and hail.

But all cold areas and places where the temperature drops below zero in winter have one more familiar phenomenon in common. These are icicles. So why do icicles appear? First you need to figure it out and ice.

Definition

According to generally accepted terminology, cooling is a phenomenon that occurs as a result of a decrease in temperature or removal of heat from an object in one way or another. For most living forms, low temperatures are as destructive as high temperatures. And by the way, absolute cold is designated as -273.15 degrees Celsius. In such conditions, not only does water freeze, but also metals become brittle, like glass, and movement practically stops elementary particles in matter.

Ice

When the temperature drops below zero degrees Celsius, water turns into ice. This is a solid state of matter that usually has liquid form. But if there is no rain in winter and all the liquid freezes, then why do icicles appear on the eaves of houses? The thing is that during winter periods the temperature can vary over fairly wide ranges, and the precipitation will begin to melt, and then the return of frost will stop this. That is why water formerly snow, begins to flow from the roofs of houses, and as the temperature drops, it gradually freezes, which is why the drops, sliding along the bases of the icicles, do not reach the ground in full, leaving part of the liquid in the form of ice.

But sometimes in winter there is no above-zero temperature at all, but ice can still be observed. Why do icicles appear in this case?

Warm

In this case, home heating comes into play. According to statistics in winter period Most houses lose up to 30% of heat through the roof, and the snow, albeit slowly, still melts. This is especially true in private homes.

Danger

These ice formations are quite dangerous. Especially in cities where there are many high-rise buildings. And all because getting to their eaves is very problematic, and icicles sometimes grow to enormous sizes. As a result, a fall can kill a bystander. And, let’s face it, getting hit on the head with even a small piece of ice falling from the 15th floor is not a pleasant experience.

Therefore, every winter, utility services spend a lot of effort trying to knock down icicles.

How to make an icicle?

There are several ways. The first one is the most “natural”. On a frosty day, you need to be patient and have a bottle of water. Then find an object on the street from which the liquid would drain slowly and evenly, and ideally drop by drop. This process is slow, but with the appearance of the first ice, things will become more fun.

The second way is to make it at any time of the year. You just need to prepare the appropriate form, fill it with water and place it in the refrigerator freezer. But the main thing to remember here is that liquid expands greatly when it freezes and can destroy the mold material, so glass is not suitable for it.

Well, the third thing is to get a block and cut a narrow long cone in the form of an icicle from it. True, it will not be an icicle in the usual sense, since dry ice consists of frozen carbon dioxide, which does not melt, but evaporates. It can also cause cold “burns” on the skin.

Now we know how icicles appear, and we have also learned how to make them.

There will certainly come a time when small world the baby will begin to expand. Now he will be concerned with more serious questions, the answers to which must be prepared in advance. After all, you must admit that when a mother or father cannot quickly find an answer to a child’s question, the baby begins to get nervous and understand that the parents, it turns out, do not know everything either. Therefore, in order not to fall into a stupor from the questions of the young why, it is better to immediately familiarize yourself with the most common questions that most children ask. And the point is not that children develop in the same way, this is far from the case. Just similar questions arise due to the fact that children, seeing the world around themselves, cannot explain why it happens this way and not otherwise.

One common question is: why do icicles appear? The answer to this is quite simple, but if you show your child clearly how they arise, the result will last a lifetime. So, icicles most often form in the spring, but they can also be observed in winter, especially if frequent temperature changes occur.

Icicles can be seen on the roofs of buildings and on tree branches, but it happens that in the spring they form everywhere, for example, on horizontal bars located in playgrounds, on slides, and so on. Such icicles appear as a result of warming, because snow, when heated by the sun, turns into melt water. And water, in turn, turns into ice when it freezes. Thus, if water flowed from a roof or from a tree branch, and the air temperature dropped at that time, it simply froze.

Snow begins to melt at an air temperature of +0 degrees, and this occurs especially effectively under the influence of sunlight. But even if the Sun is hidden behind the clouds, in the shadows, the snow will still melt. The main condition is the right temperature. The process of water freezing begins when the thermometer drops below -0 degrees. The colder the air, the faster the water turns into ice. That is why, when the first warm days of spring arrive and the Sun warms us with its rays, the snow begins to melt. However, in the evening the Sun sets and the air temperature becomes lower. All the water that came from the snow begins to freeze again. If this happens on the roof of a building, then all the water begins to go down through special drainage systems, which, as a rule, always have the most icicles. The same thing happens with trees. The snow that covered each branch melts and after some time freezes again, presenting beautiful icicles to our eyes.

But this is not the only reason why you can see shiny icicles. Sometimes they form on buildings even in winter, when the air temperature does not rise above 0. So why does this happen and how is this even possible? The fact is that residential buildings or houses are equipped with an attic or attic. In addition, the house itself is heated by central heating. It turns out that the room is warm inside, and it begins to heat the roof. So the snow that has accumulated on the roof begins to melt and, turning into water, flows from the edges of the roof or through special pipes. And since the air temperature outside is below 0, then this same water, under the influence of cold, turns into an icicle.

You can conduct a small experiment with your child and show him clearly how icicles appear. To do this, you can take any plastic bottle(best with a comfortable handle) and an awl. Fill a bottle with water and go outside with your baby in suitable weather. Now you need to make a small hole in the bottom of the bottle with an awl and hang it on a tree branch. The water will drip and freeze. If it’s very cold outside, you can hang the bottle in the evening and come back in the morning to see how the icicle turned out. Your child will be delighted.

It should be noted that when the child understands what an icicle is, then you need to bring him to a conversation about the fact that they can be life-threatening. Especially large ones that hang from roofs and can fall, thereby causing harm to health.

Nina Mikhailova

I would like to bring to your attention the wonderful stories of V. I. Morozov, which help introduce children to some natural phenomena.

How icicles grow.

March is not called fickle for nothing.

The sun will warm you during the day. The puddles on the roads glisten, the streams gurgle and shimmer, and the droplets chatter excitedly.

There will be frost at night. It will bind puddles, twist a rope around a stream, freeze icicles.

So you walk around, you don’t notice, and one morning you see a drainpipe hung with smoky icicles, And you'll be surprised: “How did this happen?”

That's how.

It's hot in the sun at noon. At least get a tan. The drops are running, the drops are rushing, the burning tears of winter are pouring.

It gets colder in the evening.

Will melt an oblique ray of sunshine will turn a snowflake into a drop. A drop rolls down the roof and cools down. From the roof to icicle and down the icicle. Slides down to the very icicle nose, just to break away and hit the pliable snow, but that was not the case.

While she was rolling down, she cooled down, but just wanted to break away - she was completely frozen.

So icicles grow in length.

The sun sinks lower, its rays warm less. The drops are running more and more lazily. They freeze higher and higher. Farther and farther from icicle nose.

So icicles grow thicker.

That's why they are covered in bumps. Each tubercle is a frozen droplet, hidden for a while, alive and cheerful.

The night will freeze the drip ringing, the snow will catch infusion. Roads will open to the farthest and most remote corners.

The morning will rise in a frosty haze. But when it warms up a little, the drops start babbling again, they start again grow icicles.

Only now it’s the other way around. First in thickness, then in length. And closer to lunch they start crying.

So all the time Icicle's life. In the morning and in the evening growing and getting fatter, and at noon he cries and loses weight.

The longer the days, the hotter the sun, the longer the drops cry icicle. He is losing more weight and becoming thinner.

Until everything is spent.

Nast.

It’s bad in a snowy forest without skis. And skiing is not easy either. The snow is deep and loose - skis fall through and their toes catch on twigs and branches. By the time you make your way through the bushes, more than one sweat will come off.

Is it the case when it comes.

Nast happens in March. When winter and spring come together and rule together. During the day the sun warms as much as it can, the snow melts - spring. At night the frost sets in, the most winter frost possible. Captures wet snow with a strong thick crust.

This dense snow is present.

It's fun to run along the bell when it comes.

Crunch, crunch, crunch - echoes under the heel. No need for heavy skis. You walk like in summer, even better.

No dirt for you, no swamp hummocks. The grass doesn't get tangled in your feet. Everything is under snow: swamps, hummocks, and dead wood. And from above crust like parquet. Yes so durable that even a huge elk does not fall through.

Go wherever you want, but by lunchtime try to be closer to the road.

Otherwise it's bad.

The snow crust will become limp under the hot rays of the sun, and you won’t even take a step here. Just right to swim in a deep snow mess.

No amount of skiing will help.

Hunters and foresters take advantage of the peculiarities of spring snow. Early in the morning they all go about their business. Hunters to search for capercaillie leks, foresters to inspect and go around distant forests. During the day they sit by the fire and drink aromatic currant tea and sunbathe. At night, in the frost, they come back home.

Icicles form at a time when the difference between day and night temperatures becomes significant. In March days it is already noticeably warming up, the snow on the roofs begins to melt. Water flows down the slope, and a droplet forms at the edge. If it is large and heavy, it will most likely fall right away. A droplet less than 5 mm in diameter remains on the edge of the roof.

It comes, the air temperature drops to zero and below, the water freezes. The drop does not have time to come off and freezes in the position in which the frost caught it. In the morning the temperature rises again. A frozen drop melts somewhat slower than the snow in the middle of the roof, so another small drop, or maybe more than one, has time to join it. A small one appears, which begins to gradually grow.

It happens that icicles appear when there is no thaw. This happens because it can be heated not only from the outside, but also from the inside - by steam heating systems or stoves. The roof warms up, the snow melts, water flows to the edges and freezes, because the temperature on the eaves is much lower than on the central sections of the roof. Ice forms and prevents water from draining. The worse the thermal insulation, the more water flows to the edges and the larger the icicles will be.

Large icicles pose a danger to pedestrians and cars, so it is very important to properly insulate roofs.

Large and small icicles

It has long been noted that in coastal countries almost no icicles are formed. There is nothing surprising about this. For example, in the Baltic countries, houses with sharp, high tiled roofs have long been built. The snow does not linger on them, which means it does not melt or flow down in streams. If the slope angle is less than 40°, icicles form much more intensively. The material from which the roof is made also plays a role. The smooth surface of the high roof does not allow snow to linger.

One of the means of combating large icicles is timely removal of snow from roofs.

Icicle shape

Having examined several icicles in the spring, you can make sure that some of them are completely smooth, while others have grooves. This is especially clearly noticeable on large icicles. The shape of the icicle depends on the composition of the water. Distilled water gives a completely smooth surface because it does not contain any salts. The higher the salt concentration, the more distinct the grooves will be, but the icicle retains its conical shape. However, there comes a time when the amount of salt reaches a certain limit, and then the icicle can take on the most bizarre shape. Using this feature, you can determine, for example, how contaminated the snow in your city is with salts.

How often have you wondered why icicles hang from roofs and canopies in winter, and how they form?

Icicle formation.

We all know that at temperatures below zero degrees Celsius, water freezes and turns into ice. The water that was snow on the roof begins to slowly melt and drain when the temperature rises, and when the temperature drops it freezes, turning into an icicle. In this case, not all drops of water, rolling down the icicles, manage to reach the ground. Such temperature changes occur for various reasons, here are some of them:

- at night the temperature can be below zero, and during the day above

— during the day the snow begins to melt under the rays of the sun

- and the main reason is that even if the temperature outside is sub-zero, then in some rooms (usually in old houses) under the roof it is warmer (above zero) and the lower layer of snow begins to melt and flow to the drains.

Fighting icicles.

Today, there are many ways to combat icicles on the roofs of buildings. These methods are divided into two main types. The first - actual - removal of already formed icicles on the roof overhangs. The second type is preventive - thermal insulation of attics, ventilation of buildings, reconstruction of roofs and gutters. This method involves keeping attics cold and prevents the formation of icicles.

Do not forget that when there is a thaw or under the weight of their own, the icicles begin to fall; be careful, do not walk under the roofs of buildings.