Eco Inform is a news agency. Eco Inform - news agency How clouds in the sky disperse

As many may remember, Dr. Felix Honniker, the character of Kurt Vonnegut's ironic dystopia Cat's Cradle, created the mysterious and terrible Ice Nine. As soon as one crystal of this ice was thrown into a puddle, all moisture on Earth, including atmospheric, began to crystallize and harden already at a positive temperature. Science fiction science fiction, but Dr. Honniker's creation has some real prototype. The writer himself was inspired by the writings of his own brother Bernard, a famous chemist and meteorologist, who figured out how to make artificial rain or snow

Laboratory Before the start of active influence on clouds from a special aircraft-meteorological laboratory, a reconnaissance of the state of clouds is carried out. A measuring and computing complex is installed on board the aircraft, which receives and processes information from a variety of sensors.

Ice torch The photo shows a liquid nitrogen atomizer installed on an An-26 aircraft

General form fine ice particle generator

Shooting at the clouds In the photo - aircraft devices for shooting squibs with silver iodide. Structurally, this "weapon" is similar to installations for shooting false heat targets

Ice-forming aerosol generator GLA-105 - based on 105-mm fireworks

Based on standard launchers - single-barrel

Based on standard launchers - multi-barrel

More precisely, Bernard Vonnegut was only one of the American scientists working in this field. Another researcher, physicist Vincent Schaefer, experimented with an artificially created supercooled cloud (that is, consisting of suspended water at sub-zero temperatures, but not crystalline). To force the water to change its state of aggregation, he “blew” finely dispersed substances (salt, talc, dust) into the cloud, the particles of which could become centers of crystallization. But somehow they didn’t. Finally, Schaefer, deciding that the temperature in the cell was not low enough, threw in a piece of dry ice (frozen carbon dioxide CO2) and ... a thick gray fog began to swirl in the air saturated with moisture, and then it snowed. Water droplets crystallized spontaneously and precipitated out. Bernard Vonnegut also achieved an effect with a similar result, but a slightly different nature (we will talk about this later) - albeit with the help of not dry ice, but silver iodide (AgJ). These two laboratory experiments were carried out in 1946 (theoretical work was carried out both in the United States and in other countries since the beginning of the 20th century). On November 13 of that year, six pounds of dry ice was sprayed from an airplane over a cloud floating along the slopes of Mount Greylock in East Massachusetts. The cloud was waking up with snow. So the first step was taken in the field of active influence on atmospheric processes.

From Chernobyl to Venice

“The first practical work on the impact on the weather began in the USSR back in the 1960s,” says Viktor Petrovich Korneev, director of the Autonomous Non-Profit Association (ANO) Agency for Atmospheric Technologies, “and it has historically developed that technologies for artificial reduction precipitation. Back in the first half of the 1980s, an experimental production laboratory was created under the Moscow City Executive Committee, which, in particular, was tasked with reducing the amount of snow falling over the capital - the city leaders wanted to save money on cleaning and removal. In addition, during the days of parades and demonstrations on May 1, 9 and November 7, work was organized to improve weather conditions... To do this, it was necessary to make sure that the clouds "intended" for Moscow would rain down somewhere outside the ring road.

A special stage was the elimination of the consequences of the accident at the Chernobyl nuclear power plant. Then the task was set to prevent radioactive dust from being washed into the Dnieper and Pripyat, covering the soil in the disaster zone. With the help of special reagents, it was possible to bind the dust, protecting it from being scattered by the wind. But the torrents of rain were a serious danger. An-12 transport aircraft and even Tu-95 long-range bombers flying to Chernobyl from the Chkalovsky airfield were sent to fight the rain clouds.

In those days, big plans were made. For example, a project was being worked out to restore the water reserves of the Aral Sea by increasing the level of precipitation in the mountains, from where the Syr Darya and Amu Darya rivers that fed the dying sea originate. But with the collapse of the USSR, research work in this area was sharply reduced. True, as it turned out, Russian technologies turned out to be very interesting to some foreign partners. In the 1990s, work to increase precipitation was carried out in Syria, and in the last decade in Iran. Our experts also took part in the project of dispersing fog on key sections of the Venice-Trieste highway (Italy) and shared their experience with Chinese colleagues on the eve of the Beijing 2008 Olympics.

Fighting clouds and fogs periodically has to be in Russia. In 1995-1997, the government of Yakutia became interested in the opportunity to increase the amount of precipitation. In a short but hot Siberian summer, this republic experienced a lack of moisture on pastures, which created problems for local livestock breeders. According to V.P. Korneev, the Moscow specialists who arrived in Yakutia were met by a representative of the regional authorities, an employee of the Institute of Northern Problems and a local shaman, who very thoughtfully expressed his own point of view on the water cycle in nature. However, the most famous and most demanded area of \u200b\u200bwork of ANO "Atmospheric Technologies" and their colleagues from the Central Aerological Observatory is still what is popularly called "cloud dispersal" over large metropolitan areas, and above all over Moscow.

Bringing up the cold

Almost all methods of influencing hydrometeorological processes are based on the use of the unstable state of the cloudy atmosphere. First of all, we are talking about the phase instability of cloudy water - this, as already mentioned, is the presence in clouds that are above the zero isotherm (this is the name of the height where the atmosphere "passes" through a temperature of 0 ° C), small droplets of moisture, which continues to remain liquid despite the negative temperature (up to -40 ° С) of the ambient air. To cause precipitation, it is required to make this water crystallize.

This can be done in two ways: either sharply cool the cloud by forcing droplets of supercooled moisture to spontaneous crystallization under the action of abrupt cooling (refrigerants are used for this), or introduce crystallization centers into it.

The most popular refrigerants for many decades have been dry ice, with which Vincent Schaeffer experimented, and liquid nitrogen (N2). The evaporation temperature for solid carbon dioxide is -78 ° C, and for liquid nitrogen -169 ° C. With all its advantages, refrigerants have a number of disadvantages, therefore, sometimes a reagent with a different mechanism of action is used - silver iodide (AgJ). Crystals of this substance are practically isomorphic to ice crystals and perfectly fulfill the function of crystallization centers for water and steam. This effect was discovered by Bernard Vonnegut, so silver iodide can be considered a distant prototype of "ice-nine" from the novel "Cat's Cradle".

As soon as crystals appear in a supercooled cloud, they immediately "eat up" the surrounding vapor; the pressure around the surface of the crystal drops, which causes the liquid moisture in the cloud to evaporate; the vapor is again absorbed by the growing crystal, and so on. The heavy crystals are dragged downward by the gravitational force of the Earth. This method can also prevent the formation of large droplets of supercooled water, which sooner or later can turn into a large hail. In addition, the use of reagents that form crystals from a supercooled liquid can not only cause precipitation, but also ... delay them. If the cloud is "re-seeded" with reagents, then due to the occurrence of too high concentration of crystallization nuclei, sedimentation will be slowed down. So “good weather specialists” always have a choice: make the cloud rain before the wind blows it over the protected area, or, conversely, “overseed” it so that the rain will pass after the cloud is gone. As a rule, the second method is used for frontal clouds.

Each type of reagent has its own dispersion technology, or "seeding". Dry ice pellets with sizes ranging from 0.2 to 2 cm are obtained directly on board the aircraft by crushing industrial briquettes. This crumb of ice is scattered above the clouds using bunker or auger devices.

For crystallization of cloudy water with liquid nitrogen, liquid nitrogen aircraft generators of fine ice particles HMCHL-A are used. Under pressure, liquid nitrogen is supplied to a sprayer installed outside the aircraft and discharged into the atmosphere, creating there a "torch" of deeply cooled air with a temperature of -90 ° C. Water entering it instantly crystallizes.

For seeding clouds with silver iodide aerosol, squibs are used, which are fired off by special automatic devices.

Cemented sky

Back in the 1950s, at the dawn of Soviet experiments to actively influence atmospheric processes, researchers faced a problem. Only a few minutes after the spraying of the reagents, the aircraft crew was already having difficulty identifying the processed cloud among many others. And without that it was not easy to track the efficiency of the work and prevent re-seeding. The solution was found in one of the numerous kerosene shops at that time. There was bought blue - a powder widely used by housewives for easy tinting of bed linen during boiling and washing. It was assumed that if, together with the reagents, we spray blue over the cloud, a bluish spot will appear on it, which will play the role of a label. However, when it came to practical experiments, it turned out that the clouds on which the blue had been poured, after a while, simply disappeared, dissipated. The disappointment that arose at first was soon replaced by the joy of discovery. After all, as it turned out, a new way of influencing the atmosphere was found - a dynamic one.

It is mainly used in the fight against vertical cumulonimbus clouds (convective clouds). These clouds, growing upward with tall "towers", can be destroyed using the same energy of atmospheric instability, which caused their appearance. Simply put, the ascending air flow, as a result of which the convective cloud grows, must be opposed by the oncoming movement, which is capable of destroying this cloud. Such movement can be created by dropping a coarse powder reagent with adsorbent properties. This can be, for example, salt or, which is most often used in domestic practice, cement. Swelling with moisture, the heavy powder will break through the cloud, dragging away the droplets of water. Cement spraying is used not only to combat convective clouds, but also to influence the so-called warm clouds below the zero isotherm. Crystallizing reagents are powerless against them - even liquid nitrogen, which has the highest temperature threshold of activity, can operate at a temperature of a cloudy environment no higher than -0.5 ° C.

The use of cement powder as a reagent raises concerns among the general public - shouldn't we all wear respirators when the weather is good for the holidays? “For the respiratory organs, the spraying of cement does not pose any danger, since after the treatment of the clouds, the concentration of powder particles in the air, which is already supersaturated with aerosols, is negligible - only 1-2 particles per m3,” V.P. Korneev. And yet, this method cannot be recognized as 100% safe. The fact is that the powder reagent is dropped from the aircraft in the form of cardboard and foam containers measuring 26 x 26 x 38 cm and weighing 25-30 kg. The container provides for automatic forced opening, after which it breaks up into fragments that are safe for people and buildings. However, on June 12, 2008, when, on the occasion of the Day of Russia, measures were taken to ensure sunny weather in Moscow, an unopened container with cement broke through the roof of a private house in the Narofominsk district of the Moscow region. Fortunately, no one died, but everyone had to make sure once again that there is no reliable technology.

We are used to the fact that on the days of big holidays, Moscow parades and festivities are not overshadowed by bad weather. The technology of local weather improvement is well developed today, although the history of this direction goes back centuries.

Everything depends on the weather

Any news includes weather forecast, too much depends on it. Our ancestors prayed for rain and tried to make the clouds rain down by ringing bells. With the advent of artillery, they began to shoot at the clouds carrying hail in order to save the harvest. But the success of these attempts was unpredictable: sometimes it worked, sometimes it didn't. Modern science has learned to control the weather at least locally. Many are interested in the question of over Moscow and whether they actually do it? Is it possible anywhere else? Isn't it harmful? Does this not spoil the climate in the neighboring areas?

Ahead of the whole planet

Russian researchers have learned to manage the weather better than others. Foreign countries only adopt domestic experience. The issue of weather management was closely tackled in the Soviet Union in the 40-50s of the last century. At first, the dispersal of clouds was purely utilitarian in nature: in the spirit of that time, they wanted to make the sky spill over agricultural land. The work was going well, and weather management was no longer a utopia.

The accumulated knowledge came in handy later in the days of the Chernobyl disaster. The goal of the scientists was to save the Dnieper from radioactive contamination. The attempt was successful. If it were not for the efforts of scientists and the military, the size of the disaster would have been much larger.

How do the clouds disperse over Moscow today? In general, the same as 60 years ago.

Cloud dispersal technology

The first step is to determine how far from the desired location the rain clouds are. An accurate forecast is required 48 hours before the estimated time, for example, before the parade. Then the composition and characteristics of the clouds are studied: each of them needs its own reagent.

The meaning of the technology lies in the fact that a reagent is placed in the center of the cloud, on which moisture adheres. When the amount of concentrated moisture becomes critical, it starts to rain. The cloud spills before the place where the cloud was directed along the air currents.

The following substances are used as reagents:

• dry ice (carbon dioxide) in granules;
• iodide silver;
• a liquid nitrogen;
• cement.

How do the clouds disperse over Moscow?

For this, clouds are processed at a distance of 50 or 100 km from the place where rain is not needed.

Used for stratus clouds closest to the ground. This composition is poured onto clouds at an altitude of several thousand meters. Special navigation is applied, the processed clouds are marked so that there is no re-exposure.

Nimbostratus clouds, located above, get liquid nitrogen, or rather crystals of its soaring. Special large-capacity aircraft are installed on the aircraft and sprayed over the cloud. This is how the clouds in Moscow are dispersed using the chemistry known to all.

Silver iodide is placed in special meteo cartridges and shot at high rain clouds. These dense clouds are composed of ice crystals, and their lifetime does not exceed 4 hours. The chemical structure of silver iodide is very similar to ice crystals. After getting into a rain cloud, condensation centers quickly form around it, and rain soon falls. At the same time, there may be a thunderstorm or even hail, such is the property of these clouds.

However, this is an incomplete answer to the question of how the clouds are dispersed over Moscow. Sometimes dry cement is also used. The cement package (standard paper bag) is hooked onto the hook. The exposure to the air flow gradually tears the paper apart and the cement is gradually blown out. It combines with water and drops fall to the ground. Cement is used to treat the air to stop cloud formation.

Is it harmful to disperse the clouds?

This issue is constantly discussed by residents of the regions bordering on the Moscow region, especially the Smolensk region. The logic is simple: as the clouds disperse over Moscow on May 9, it rains endlessly.

It would seem that the reagents can not bring much harm, these substances have long been well studied. However, to disperse the clouds, up to 50 tons of reagents are used at a time. To date, there are no studies that could prove or disprove the harm caused to nature. Ecologists say that the chronology of precipitation is disrupted, and that's all.

Even lawsuits for moral damage have been recorded, but not a single claim has yet been satisfied. The discontent of the residents of the Moscow region can be explained very simply: they feel themselves to be unequal citizens. Residents of cities and towns surrounding Moscow are forced to spend more or less significant holidays with rain, even if no precipitation was predicted.

At the same time, people recognize that the dispersal of clouds is simply necessary in the event of a threat to crops or housing, when a hurricane or hail is foreseen. Have a large number residents resent the way the clouds are dispersed in Moscow on holidays, because they have the same holiday completely ruined.

Many people are interested in dispersing clouds. Indeed, a very interesting topic. How are they dispersed? How much money does it take? In general, it is worth noting that you really have to spend a lot. This pleasure is now very expensive. So, one of the last holidays cost the Russian government 430 thousand rubles. This is a very large amount. Many consider it a waste of money. But it's interesting all the same. How to disperse clouds?

What holidays do the clouds disperse?

Let's see what holidays they do? And how do rain clouds disperse? In general, the main dates are as follows: May 9, July 12 and the first Saturday in September. It's at four o'clock in the morning the plane is taking off His goal is very simple - to scout the current situation. If there is a threat of rain, planes with reagents rise. There are also special generators of fine particles. Cylinders with reagents are connected to them. They then dissipate under high pressure. As a result, precipitation falls.

When did the clouds begin to disperse?

The first attempts began shortly after the Second World War. In this area, all the advanced developments went to the Americans. They suggested using two substances - and for these purposes. In the Soviet Union, they began to do this somewhere in the early 60s. That is, late enough.

There is nothing complicated in the process. But this process is called a little differently. It's not cloud dispersal after all. In fact, the clouds are raining and just disappear. To disperse clouds in the classical sense of this term, you need to be able to create a very strong wind. Unfortunately, they have not yet learned how to do this. By the way, it would be nice. After all, you can save a lot in this case. But so far, completely different methods of dispersing clouds are used.

They can also do this using special self-opening containers. The technology is cheaper, but there is a risk that they will not open on their own and fall to the ground. And they are far from easy. Therefore, it can even lead to injury. Although these arguments are not so critical due to the fact that you often have to disperse clouds over uninhabited parts of the country. But if you have to do this over some village, then you need to be more careful.

When was the ability to overclock the clouds useful in practice?

The ability to disperse clouds in practice was needed after the Chernobyl disaster. The rains were very dangerous at the time. Therefore, it was necessary to be able to create precipitation directly in the exclusion zone and in no case should it be allowed in other parts of the planet. It was a very important task. That's when there was a really practical benefit to scattering clouds. But now there is not much sense, to be honest. Although some people may think otherwise. Still, good weather is a guarantee of good mood.

What reagents are used?

Now let's take a closer look at how to disperse the clouds. What reagents are used to make this task a reality?

1. A liquid nitrogen.
2. Dry ice.
3. Granular carbon dioxide.
4. Special cement. This material also raises doubts about environmental friendliness.
5. Silver iodide. It is used in completely hopeless cases.

As you can see, a fairly large number of reagents are used to accomplish this task. It all depends on what kind of cloud layer you want to dissipate. It also affects what material is used, the type of cloud. Not every cloud can be dispelled, as it turns out. So science still has room to grow. However, the technology of using such a substance as silver iodide is quite new.

Arguments for dispersing the clouds

Naturally, there are defenders and opponents of the dispersal of clouds. And there is nothing strange here. This procedure is really controversial. For objectivity, you need to consider the arguments of both the one and the other side. And you yourself decide. So, the clouds need to be dispersed, because:

• Good weather improves your mood. And these are not unfounded statements. Indeed, under the influence of light, and even more so the sun's rays, the level of serotonin in the blood of a person increases. It is called the "hormone of happiness". Consequently, the feeling of celebration is enhanced.
• None of the events in which money has been invested will fail. This is especially true as an argument against supporters of the opinion that the cost of overclocking is very high. In general, the holidays cost a lot of money. Is there any point in holding them then?
• The technological level of the country is shown. This is more about foreign policy. Although this argument is rather dubious. But since some people use it, it makes sense to bring it here.

There are few reasons. Indeed, they are weighty enough for some people. Especially if there are some open-air events.

Arguments against the dispersal of clouds

There are also arguments from people who do not care how to disperse the clouds if it is so expensive. For them, just knowing the amount that will have to be spent on it is enough. At the same time, there are more loyal people who are still against it. But not so categorically. What arguments do they have?

1. The cost does not justify the results. Everything is extremely simple here. The money spent on such work can be used in a more constructive direction. For example, you can implement the construction of new parking lots or road junctions. These are more constructive elements. Or, for example, sewage and rainwater drainage can be improved. Now actively going global warming... Therefore, the precipitation became more extensive. Soon the city sewers will not be able to withstand this strain. But people want a clear sky. In general, a controversial decision. Still, the question "how much does it cost to disperse the clouds" is in the first place.
2. Environmental problems. Some people think that reagents are not environmentally friendly. Of course, this is a moot point. Many researchers say that there is nothing wrong with that. But sometimes, because of the dispersal of clouds, farms suffer. Many villagers complain that when they do this work, they just need rain. And the clouds do not reach the fields, having spilled over the city. Everything should go on as usual in nature. Now it is not known exactly what the local precipitation of such strong precipitation can lead to. The same goes for the effects of these reagents on humans. After all, mercury and radiation were previously considered safe. But then these theses were refuted.

In general, the arguments are no less weighty than those of the supporters. We figured out how to disperse the clouds. It turns out that there is nothing very complicated about this. If you have money, you can do the same. After all, you now also know how clouds disperse. Over Moscow, you have to do this quite often, especially in a cloudy rainy autumn.