Emergency situations of a meteorological nature. Public protection

From the very beginning of the development of civilization, the planet has been threatened by emergencies of a geological, meteorological, hydrological nature. However, they often cause significant damage. The magnitude of the damage depends on the intensity of disasters, the conditions of life of the society, the level of its development. Let us further consider the main meteorological emergencies.

Relevance of the issue

Recently, emergencies of a geological, meteorological, hydrological and biological nature have become more frequent. So, for example, volcanoes in Kamchatka are activated, the number of earthquakes in the North Caucasus, Transbaikalia, Sakhalin and the Kuril Islands is growing. The destructive power of disasters is increasing. Recently, floods, landslides, tornadoes, storms, hurricanes, snowdrifts, and other emergencies of a meteorological and agrometeorological nature have become almost regular . Undoubtedly, today mankind is not as helpless as before. Some disasters can be successfully predicted, while others can be effectively resisted. But any response to natural processes requires a deep knowledge of the causes and characters of manifestation.

Patterns

Natural meteorological emergencies have a number of common features:

1. Each type of disaster is characterized by a specific spatial reference.
2. The higher the power (intensity) of the phenomenon, the less often it occurs.
3. Each phenomenon is preceded by certain signs.
4. For all the suddenness, the occurrence of a disaster can be predicted.
5. Almost always, active or passive measures aimed at protecting against danger can be envisaged.

Causes of meteorological emergencies: examples

Disasters can be caused by various factors. Among the most common are:

1. Wind, including tornado, storm, hurricane. Emergencies of a meteorological nature occur at an air velocity of 25 m / s or more.
2. Heavy rain - rainfall of 50 mm or more for 12 hours.
3. Large hail - particle diameter from 20 mm.
4. Heavy snowfall - rainfall from 20 mm in 12 hours
5. Dust storms.
6. Heavy snowstorms with wind speeds of 15 m / s and above.
7. Frosts - with a decrease in temperature on the soil surface during the growing season below 0 deg.
8. Heatwave.

Squally winds, rains, frosts and can cause serious damage to livelihoods, threaten the life of the population. Natural meteorological emergencies can cause catastrophic consequences when:

1. Occur in the region (region, region, republic, district).
2. Cover several areas.
3. Lasts at least 6 hours.
   

Air movement

The planet’s atmosphere is heterogeneous in both temperature and composition. The temperature difference provides general air circulation. It, in turn, has an impact on climatic conditions on the planet. The movement of air is called the wind. His strength is evaluated in accordance with the Beaufort scale in points (from 0 to 12). The movement of air is determined by the presence of anticyclones and cyclones. The wind always goes from the high pressure zone to the low zone. In diameter, the cyclone can reach several thousand kilometers. In the Northern Hemisphere , the wind direction is opposite, and in the Southern Hemisphere - clockwise.

Hurricanes

They are distinguished by high speed. She can reach 12 points. Over the Pacific Ocean, tropical hurricanes arise - typhoons. They are considered the most powerful meteorological emergencies . Hurricanes can have different sizes. As a rule, the destruction zone is taken as the width. Often a small area of ​​storm winds is added to it. In such cases, the width of the hurricane can reach even 1 thousand km. The destruction zone of a typhoon, as a rule, is 15-45 km. The duration of hurricanes is an average of 9-12 days. The power of destruction is determined by the presence of colossal energy in the epicenter. Its amount released within 1 hour is comparable with the strength of a nuclear explosion of 36 gigatons. Often, other meteorological emergencies occur along with hurricanes. In particular, the phenomena are accompanied by heavy rains causing landslides and mudflows.

Storm

They are streaming and vortex. The latter are presented in the form of complex formations, the occurrence of which is associated with cyclonic activity. They spread over a fairly large area. Streaming storms are local phenomena. They cover a small area. Stream storms are sharply isolated, peculiar and inferior to vortex ones. They can be jet and stock. In the latter case, the air moves from top to bottom. In jet storms, streams move horizontally and upward. As a rule, they pass between the mountain ranges connecting the valleys. A meteorological emergency also includes dust storms. They cause choking, can carry dangerous parasites, cause significant damage to equipment. As a rule, such phenomena occur in deserts, with unstable weather, in the zone of atmospheric fronts. Squall storms usually begin suddenly. Moreover, they differ in a short nature (up to several minutes).

Tornado

As a rule, it occurs in a warm section of the cyclone and moves with it at a speed of 10-20 m / s. The length of the tornado path can be from 1 to 60 km. In its upper part, a funnel-shaped expansion forms, which merges with the clouds. In some cases, the lower part increases. This happens when the tornado is reduced to the ground. Its height can be 800-1500 m. In a tornado, air rotates and simultaneously moves upward in a spiral, drawing water and dust into itself. The speed of such a flow can be 330 m / s. Inside the vortex, a decrease in pressure occurs. As a result, steam condensation begins. A tornado becomes visible due to water and dust. Over the sea, its diameter can reach tens, and over land - hundreds of meters. Along with the tornado, thunderstorms, hail, and rain often arise. If streams reach the earth, the objects on it are always destroyed. A tornado drags in all the objects that meet on the way, picks them up and carries them over long distances. Such weather conditions are very difficult to predict.

Shower

It is an intense rainfall. Particularly dangerous showers, the speed of which is 0.15-0.20 mm / minute. They damage crops, causing them to lodge. Long rains cause floods. In addition, they cause dangerous slope processes (liquefaction of the soil, landslides, mudflows).

Snowfall

It complicates the movement of vehicles, significantly reduces visibility. In 12 hours, 20 mm or more may fall. Heavy snowfalls with drifts completely paralyze traffic, cause damage to power lines, buildings (due to high layer pressure). In this case, snowstorms are frequent - the transfer of snow by the wind. The lower their intensity, the longer they last.

Frost

During the growing season, a significant decrease in temperature leads to the death of crops. In the northern regions, freezing is a frequent occurrence. Extremely low temperature drops are characteristic of Kamchatka, Chukotka, Yakutia, and the Magadan region. The magnitude of the damage will depend not so much on the level of deviation from normal indicators t, but on the adaptability of the local population and the economic complex to such phenomena.

Heat

In summer, an extreme temperature increase is frequent. Heat can stand for one or several weeks. Emergency mode is announced when the temperature reaches 35 degrees. Heat increases the risk of fires, shallowing of rivers, damages crops. In many cases, it leads to disruptions in the operation of the transport. Often heat causes drought. Over a vast territory, a high temperature is maintained for a long time, combined with the lack of precipitation. If this situation persists for at least a month, then the water balance of the plants is disrupted, which leads to damage and death.

Meteorological Emergency Rules

There are various recommendations on how to behave when disasters occur. Any person needs to know what to do in case of emergency of a meteorological nature , since not only his life, but also his relatives can depend on it. Elementary recommendations are given back in school. In the OBZh lessons, the teacher talks about emergencies and the rules of conduct when they occur.

Thunderstorm Events

Lightning carries danger when a flash of thunder follows the flash. In such situations, urgent security measures are required. When in the house, it is necessary to close windows, chimneys, doors, ventilation holes. Do not heat the furnace, since the gases that will exit the pipe are characterized by low resistance. When lightning strikes, you can not approach the wiring, gutters, lightning conductor. It is not recommended to be near the window. It is advisable to turn off household appliances. If you are in a forest during a thunderstorm, you should choose a low section. It is dangerous to take refuge in tall trees. From the elevations it is better to go down to the lowland. When in open space (in a field, steppe), one should not lie down on the ground. It is necessary to choose a depression and sit down, clasping hands with legs.

Measures for a hurricane, tornado, storm

When you are in the building, you need to move away from the windows and take a safe place in the corridor, against walls, built-in wardrobes, under a table, etc. First you need to turn off the lights, close the taps on gas equipment, put out the fire in the stove. In the dark, you should use lamps, candles, lights. If a hurricane is found on the street, you must try to stay away from light structures, bridges, power lines, overpasses, lakes, rivers, masts, trees, industrial facilities. To protect yourself from flying debris, you can use sheets of plywood, boxes, boards and other improvised materials. It is necessary to take refuge in the basement, anti-radiation shelter, cellar, etc. as soon as possible. Do not enter damaged buildings, since there is a high risk of collapse. With a dust storm, it is necessary to cover the face with a bandage, a piece of cloth, a scarf. When you are in an open area you should find a road ditch, a hole, a ditch, any other depression and lie down in it, clinging tightly to the ground. The head must be covered with clothes or branches. In a car in this situation, staying dangerous.

Snowstorm Activities

Exit buildings is possible only in exceptional cases. Moving in a car is possible only on major highways. When exiting the vehicle, do not move away from it beyond the limits of visibility. The Ministry of Emergencies warns that during the elements the number of thefts and other crimes increases. In this regard, caution is required when dealing with strangers.

Conclusion

Considering natural emergencies, it is necessary to note the importance of anthropogenic impact on their occurrence. Human activities often upset the balance in ecosystems. This, in turn, leads to an increase in the intensity and frequency of emergencies. A catastrophe can affect any area of ​​the earth. There is always a connection between emergencies. It is most clearly manifested in earthquakes and tsunamis. Cyclones in the tropics are almost always followed by floods. Earthquakes often cause fires, dam breaks, etc. When planning protective measures, it is necessary to minimize the size of the secondary consequences. Through appropriate training, they can be completely eliminated. To successfully prevent and eliminate emergencies, it is necessary to study their causes and mechanisms. It is possible to predict the occurrence of a particular phenomenon, knowing its physical nature.

Protection from natural disasters of meteorological, geological, hydrological and other nature can be active. In this case, the construction of engineering structures and structures, the mobilization of resources, reconstruction of facilities, etc. is carried out. Protection can also be passive. In this case, the population uses shelters. As a rule, passive and active defense methods are combined.