Meteorological natural phenomena - life safety: Fundamentals of life safety. Natural phenomena of meteorological origin What refers to dangerous meteorological phenomena

Dangerous atmospheric phenomena (signs of approach, damaging factors, preventive measures and protective measures)

Meteorological and agrometeorological hazards

Meteorological and agrometeorological hazards are divided into:

storms (9-11 points):

hurricanes (12-15 points):

tornadoes;

vertical vortices;

large hail;

heavy rain (rain);

heavy snowfall;

heavy ice;

severe frost;

severe snowstorm;

heatwave;

heavy fog;

frosts.

Fog is the concentration of small drops of water or ice crystals in the surface layer of the atmosphere from air saturated with water vapor as it cools. In fogs, horizontal visibility is reduced to 100 m or less. Depending on the horizontal visibility range, there is heavy fog (visibility up to 50 m), moderate fog (visibility less than 500 m) and light fog (visibility from 500 to 1000 m).

A slight clouding of the air with horizontal visibility of 1 to 10 km is called a veil. The veil can be strong (visibility 1-2 km), moderate (up to 4 km) and weak (up to 10 km). Fogs are distinguished by origin: advective and radiation. Deteriorating visibility complicates the work of transport - flights are interrupted, the schedule and speed of ground transport changes. Drops of fog, settling on the surface or ground objects under the influence of gravity or air flow, moisten them. There have been repeated cases of overlapping of insulators high voltage lines power transmission lines as a result of drops of fog and dew settling on them. Fog drops, like dew drops, are a source of additional moisture for field plants. As the droplets settle on them, they maintain high relative humidity around them. On the other hand, drops of fog, settling on plants, contribute to the development of rotting.

At night, fogs protect vegetation from excessive cooling as a result of radiation, weaken bad influence frosts. During the day, fogs protect vegetation from solar overheating. The settling of fog droplets on the surface of machine parts leads to damage to their coatings and corrosion.

Based on the number of days with fog, Russia can be divided into three parts: mountainous regions, central highlands and lowland regions. The frequency of fogs increases from south to north. A slight increase in the number of days with fog is observed in spring. Fogs of all types can be observed at both negative and positive soil surface temperatures (from 0 to 5°C).

Black ice - atmospheric phenomenon, which is formed as a result of freezing drops of supercooled rain or fog on the surface of the earth and objects. It is a layer of dense ice, transparent or matte, which grows on the windward side.

The most significant icy conditions are observed during the passage of southern cyclones. When cyclones move east from the Mediterranean Sea and fill them over the Black Sea, icy conditions are observed in the south of Russia.

The duration of black ice varies - from parts of an hour to 24 hours or more. Formed black ice long time sticks to objects. As a rule, black ice forms at night at negative air temperatures (from 0° to - 3°C). Black ice along with strong wind causes significant damage to the household: wires break under the weight of icing, telegraph poles fall, trees die, traffic stops, etc.

Frost is an atmospheric phenomenon that is the deposition of ice on thin long objects (tree branches, wires). There are two types of frost: crystalline and granular. The conditions of their formation are different. Crystalline frost is formed during fog as a result of sublimation (the formation of ice crystals directly from water vapor without its transition to a liquid state or during rapid cooling below 0 ° C) of water vapor, consists of ice crystals. Their growth occurs on the windward side of objects in light winds and temperatures below - 15°C. The length of the crystals, as a rule, does not exceed 1 cm, but can reach several centimeters. Granular frost is snow-like loose ice that grows on objects in foggy, mostly windy weather.

It has sufficient strength. The thickness of this frost can reach many centimeters. Most often, crystalline frost occurs in the central part of the anticyclone with high relative humidity air below the inversion layer. According to the conditions of formation, granular frost is close to glaze. Frost is observed throughout Russia, but is distributed unevenly, since its formation is influenced by local conditions - terrain height, relief shape, slope exposure, protection from the prevailing moisture-carrying flow, etc.

Due to the low density of frost (volume density from 0.01 to 0.4), the latter only causes increased vibration and sagging of power and communication wires, but can also cause their breaks. Frost poses the greatest danger to communication lines during strong winds, since the wind creates additional load on the wires, which sag under the weight of deposits, and the risk of their breakage increases.

A blizzard is an atmospheric phenomenon that is the transfer of snow over the surface of the earth by the wind with deterioration of visibility. There are such snowstorms as drifting snow, when most snowflakes rise a few centimeters above the snow cover; a blowing snow, if the snowflakes rise to 2 m or higher. These two types of snowstorms occur without snow falling from the clouds. And, in the end, a general, or upper, snowstorm - snowfall with strong winds. Snowstorms reduce visibility on the roads and interfere with transport.

A thunderstorm is a complex atmospheric phenomenon in which electrical discharges (lightning) occur in large rain clouds and between the clouds and the ground, which are accompanied by a sound phenomenon - thunder, winds and rainfall, often hail. Lightning strikes damage ground objects, power lines and communications. Squalls and downpours, floods and hail accompanying thunderstorms cause damage to agriculture and some areas of industry. There are intramass thunderstorms and thunderstorms that occur in areas of atmospheric fronts. Intramass thunderstorms are usually short-lived and occupy a smaller area than frontal thunderstorms. They arise due to strong heating of the underlying surface. Thunderstorms in the area atmospheric front differ in that they often appear in the form of chains of thunderstorm cells that move parallel to each other, covering a large area.

They occur on cold fronts, occlusion fronts, and also on warm fronts in warm, humid, typically tropical air. The zone of frontal thunderstorms is tens of kilometers wide with a front length of hundreds of kilometers. Approximately 74% of thunderstorms are observed in the frontal zone, other thunderstorms are intramass.

During a thunderstorm you should:

in the forest, take refuge among low trees with dense crowns;

in the mountains and in open areas, hide in a hole, ditch or ravine;

place all large metal objects 15-20 m away from you;

having taken refuge from the thunderstorm, sit down with your legs tucked under you and your head down on your legs bent at the knees, with your feet together;

put under yourself, plastic bag, branches or spruce branches, stones, clothes, etc. isolating itself from the soil;

on the way, the group should disperse, walk one at a time, slowly;

in the shelter, change into dry clothes, or, as a last resort, thoroughly wring out the wet ones.

During a thunderstorm you cannot:

take shelter near solitary trees or trees that protrude above others;

lean against or touch rocks and steep walls;

stop at the edges of the forest, large clearings;

walk or stop near bodies of water and in places where water flows;

hide under rock overhangs;

run, fuss, move in a dense group;

wear wet clothes and shoes;

stay on high ground;

be near watercourses, in crevices and cracks.

blizzard

A snow storm is one of the types of hurricane, characterized by significant wind speeds, which contributes to the movement of huge masses of snow through the air, and has a relatively narrow range of action (up to several tens of kilometers). During a storm, visibility deteriorates sharply, and transport links, both intracity and intercity, may be interrupted. The duration of the storm varies from several hours to several days.

Blizzards, blizzards, and blizzards are accompanied by sudden changes in temperature and snowfall with strong gusts of wind. Temperature changes, snow and rain at low temperature and strong winds, creates conditions for icing. Power lines, communication lines, roofs of buildings, various types of supports and structures, roads and bridges are covered with ice or wet snow, which often causes their destruction. Ice formations on the roads make it difficult and sometimes even completely prevent work road transport. Pedestrian movement will be difficult.

Snow drifts occur as a result of heavy snowfalls and blizzards, which can last from several hours to several days. They cause disruption of transport communications, damage to communication and power lines, and negatively affect economic activity. Snow drifts are especially dangerous when snow avalanches from the mountains

Main damaging factor Such natural disasters are the effects of low temperatures on the human body, causing frostbite and sometimes freezing.

In the event of an immediate threat, the population is notified, the necessary forces and means, road and utility services are put on alert.

A blizzard, snowstorm or blizzard can last for several days, so it is recommended to create a supply of food, water, fuel in the house in advance, and prepare emergency lighting. You can leave the premises only in exceptional cases and not alone. Restrict movement, especially in rural areas.

You should only travel by car on main roads. In the event of a sharp increase in wind, it is advisable to wait out the bad weather in or near a populated area. If the machine breaks down, do not move out of sight from it. If further movement is impossible, you should mark a parking lot, stop (with the engine facing upwind), and cover the engine on the radiator side. In case of heavy snowfall, make sure that the car is not covered with snow, i.e. Rake snow as needed. The car engine must be periodically warmed up to avoid it from “defrosting”, while preventing exhaust gases from entering the cabin (body, interior), for this purpose, make sure that the exhaust pipe is not blocked with snow. If there are several cars, it is best to use one car as a shelter, and drain the water from the engines of the remaining cars.

Under no circumstances should you leave your shelter (car); in heavy snow, landmarks may be lost after several tens of meters.

You can wait out a blizzard, blizzard or blizzard in a shelter equipped with snow. It is recommended to build a shelter only in open areas, where snow drifts are excluded. Before taking cover, you need to find landmarks on the ground in the direction of the nearest housing and remember their location.

Periodically it is necessary to control the thickness of the snow cover by piercing the ceiling of the shelter, and clear the entrance and ventilation hole.

You can find an elevated, steadily standing object in an open and snowless area, hide behind it, and constantly throw away and trample down the growing snow mass with your feet.

In critical situations, it is permissible to completely bury yourself in dry snow, for which you should put on all your warm clothes, sit with your back to the wind, cover yourself with plastic wrap or a sleeping bag, pick up a long stick and let the snow cover you. Constantly clear the ventilation hole with a stick and expand the volume of the resulting snow capsule in order to be able to get out of the snow drift. A guide arrow should be placed inside the resulting shelter.

Remember that a blizzard, due to multi-meter snow drifts and drifts, can significantly change appearance terrain.

The main types of work during snow drifts, blizzards, blizzards or blizzards are:

searching for missing people and providing them with first aid, if necessary;

clearing roads and areas around buildings;

providing technical assistance to stranded drivers;

elimination of accidents on utility and energy networks.

Hail is an atmospheric phenomenon associated with the passage of cold fronts. Occurs during strong rising air currents during warm seasons. Droplets of water, falling to great heights with air currents, freeze, and ice crystals begin to grow on them in layers. The drops become heavier and begin to fall down. When falling, they increase in size from merging with droplets of supercooled water. Sometimes hail can reach the size of a chicken egg. Typically, hail falls from large rain clouds during a thunderstorm or rainstorm. It can cover the ground with a layer of up to 20-30 cm. The number of days with hail increases in mountainous areas, on hills, and in areas with very rough terrain. Hail falls mainly in the afternoon in relatively small areas of several kilometers. Hail usually lasts from a few minutes to a quarter of an hour. Hail causes significant property damage. It destroys crops, vineyards, knocks flowers and fruits off plants. If hailstones are large in size, they can cause destruction of buildings and loss of life. IN given time Methods for identifying hail clouds have been developed, and a hail control service has been created. Dangerous clouds are “shot” with special chemicals.

Dry wind - hot and dry wind with a speed of 3 m/s or more, s high temperature air up to 25°C and low relative humidity up to 30%. Dry winds are observed in partly cloudy weather. Most often they occur in the steppes on the periphery of anticyclones that form over the North Caucasus and Kazakhstan.

The highest dry wind speeds were observed during the day, and the lowest at night. Dry winds cause great damage to agriculture: they increase the water balance of plants, especially when there is a lack of moisture in the soil, since intensive evaporation cannot be compensated by the supply of moisture through root system. With prolonged exposure to dry winds, the above-ground parts of plants turn yellow, the foliage curls, and they wilt and even die of field crops.

Dust, or black, storms - the transfer of large amounts of dust or sand by strong winds. They occur during dry weather due to the movement of sprayed soil over vast distances. On the occurrence, frequency and intensity of dust storms big influence orography, the nature of the soil, forest cover and other features of the area have an impact.

Most often, dust storms occur from March to September. The most intense and dangerous spring dust storms occur during a prolonged absence of rain, when the soil dries out and the plants are still poorly developed and do not form a continuous cover. At this time, storms blow away soil over vast areas. Horizontal visibility is reduced. S.G. Popruzhenko investigated a dust storm in 1892 in southern Ukraine. This is how he described it: "Dry, strong Eastern wind for several days it tore up the earth and drove away masses of sand and dust. The crops, which were turning yellow from the dry air, were cut at the roots, like with a sickle, but the roots could not survive. The earth was demolished to a depth of 17 cm. The channels are filled up to 1.5 m.

Hurricane

Hurricane is the wind destructive force and significant duration. A hurricane occurs suddenly in areas with a sharp change in atmospheric pressure. Hurricane speed reaches 30 m/s or more. In my own way harmful effects a hurricane can be compared to an earthquake. This is explained by the fact that hurricanes carry colossal energy; the amount of energy released by an average hurricane in one hour can be compared with the energy of a nuclear explosion.

A hurricane can cover an area up to several hundred kilometers in diameter and can travel thousands of kilometers. At the same time, hurricane winds destroy strong and demolish light buildings, devastate sown fields, break wires and knock down power and communication line poles, damage highways and bridges, break and uproot trees, damage and sink ships, and cause accidents in public utility networks. . There were cases when hurricane winds threw trains off the rails and knocked down factory chimneys. Hurricanes are often accompanied by heavy rainfall, which causes flooding.

A storm is a type of hurricane. The wind speed during a storm is not much less than the speed of a hurricane (up to 25-30 m/s). Losses and destruction from storms are significantly less than from hurricanes. Sometimes strong storm called a storm.

A tornado is a strong small-scale atmospheric vortex with a diameter of up to 1000 m, in which the air rotates at a speed of up to 100 m/s, which has great destructive power (in the USA it is called a tornado).

On the territory of Russia, tornadoes are observed in Central region, Volga region, Urals, Siberia, Transbaikalia, Caucasian coast.

A tornado is an upward vortex consisting of extremely rapidly rotating air mixed with particles and moisture, sand, dust and other suspended matter. On the ground, it moves in the form of a dark column of rotating air with a diameter of several tens to several hundred meters.

In the internal cavity of a tornado, the pressure is always low, so any objects that are in its path are sucked into it. average speed The tornado moves at 50-60 km/h, and as it approaches, a deafening roar is heard.

Strong tornadoes travel tens of kilometers and tear off roofs, uproot trees, lift cars into the air, scatter telegraph poles, and destroy houses. Notification of a threat is carried out by issuing the “Attention to all” signal with a siren and subsequent voice information.

Actions upon receiving information about an impending hurricane, storm or tornado - you should carefully listen to the instructions of the management body for civil emergency situations, which will indicate the expected time, strength of the hurricane and recommendations on rules of conduct.

Upon receipt of a storm warning, it is necessary to immediately begin carrying out preventive work:

strengthen insufficiently strong structures, close doors, dormer openings and attic spaces, cover the windows with boards or cover them with shields, and cover the glass with strips of paper or fabric, or, if possible, remove it;

in order to balance the external and internal pressure in the building, it is advisable to open doors and windows on the leeward side and secure them in this position;

It is necessary to remove things from roofs, balconies, loggias and window sills that could cause injury to people if they fall. Items located in courtyards must be secured or brought indoors;

It is also advisable to take care of emergency lamps - electric lamps, kerosene lamps, candles. It is also recommended to create supplies of water, food and medicine, especially dressings;

extinguish the fire in the stoves, check the condition of electrical switches, gas and water taps;

take pre-prepared places in buildings and shelters (in the case of tornadoes - only in basements and underground structures). Indoors, you need to choose the safest place - in the middle part of the house, in the corridors, on the ground floor. To protect against injury from glass fragments, it is recommended to use built-in cabinets, durable furniture and mattresses.

The safest place during a storm, hurricane or tornado is shelters, basements and cellars.

If a hurricane or tornado finds you in an open area, it is best to find any natural depression in the ground (ditch, hole, ravine or any notch), lie down at the bottom of the depression and press tightly to the ground. Leave the vehicle (no matter what you are in) and take refuge in the nearest basement, shelter or recess. Take measures to protect against rainfall and large hail, because hurricanes are often accompanied by them.

be on bridges, as well as in close proximity to facilities that use toxic, potent and flammable substances in their production;

take cover under isolated trees, poles, and come close to power line supports;

be near buildings from which tiles, slates and other objects are blown away by gusts of wind;

After receiving a message that the situation has stabilized, you should leave the house carefully; you need to look around to see if there are any overhanging objects or parts of structures, or broken electrical wires. It is possible that they are energized.

Unless absolutely necessary, do not enter damaged buildings, but if such a need arises, then this must be done carefully, making sure that there is no significant damage to stairs, ceilings and walls, fires, breaks in electrical wires, and you should not use elevators.

The fire should not be lit until it is certain that there is no gas leak. When outdoors, stay away from buildings, poles, high fences, etc.

The main thing in these conditions is not to give in to panic, to act competently, confidently and wisely, to prevent yourself and to restrain others from unreasonable actions, and to provide assistance to the victims.

The main types of injury to people during hurricanes, storms and tornadoes are closed injuries various areas bodies, bruises, fractures, concussions, wounds accompanied by bleeding.

Dangerous meteorological phenomena- these are natural processes and phenomena occurring in the atmosphere, which, due to their intensity (strength), scale of distribution and duration, have or can have a damaging effect on people, farm animals and plants, economic objects and the natural environment.

Such phenomena include:

1. Very strong wind

The average wind speed is at least 20 m/s, on the sea coast and in mountainous areas at least 25 m/s. Instantaneous wind speed (gust) of at least 25 m/s, on the sea coast and in mountainous areas of at least 30 m/s.

A sharp short-term increase in wind. Instantaneous wind speed (gust) of more than 25 m/s for at least 1 minute.

A strong small-scale atmospheric vortex in the form of a column or funnel, directed from the cloud to the surface of the earth

4. Heavy rain

Heavy rain shower. The amount of liquid precipitation is at least 30 mm over a period of no more than 1 hour

5. Very heavy rain

Significant liquid and mixed precipitation (rain, heavy rain, sleet, sleet). Precipitation amount of at least 20 mm over a period of no more than 1 hour

6. Very heavy snow

Significant solid precipitation (snow, heavy snow, etc.). The amount of precipitation is at least 20 mm over a period of no more than 12 hours.

7. Continued heavy rain

Continuous rain (with breaks of no more than 1 hour) for several days. The amount of precipitation is at least 120 mm over a period of at least 2 days.

8. Large hail

Hailstone diameter more than 20 mm

9. Heavy snowstorm

General or blowing snow with strong winds, causing a significant decrease in visibility. Average wind speed not less than 15 m/s, MDV not more than 500 meters

10. Strong dust storm

Blowing dust or sand in strong winds, causing severe impairment of visibility. Average wind speed is not less than 15 m/s, MDV is not more than 500 meters.

11. Heavy fog

Fog with significantly reduced visibility. MDV no more than 50 meters

12. Ice and frost deposits

Heavy deposits on street lighting wires (ice icing machine). Diameter, mm, no less: Ice 20, Complex sediment 30, Wet snow 35, Frost 50.

13. Extreme heat

High Maximum temperature air for a long period of time. The maximum air temperature is not less than 35°C for 5 days.

14. Severe frost

Low minimum air temperature for an extended period of time. Minimum temperature no more than -35°C for 5 days.

In addition to the environmental impact, there are also hydrometeorological phenomena that significantly complicate or hinder the activities of individual enterprises and sectors of the economy, but their values ​​do not reach the environmental impact criteria. The criteria for these phenomena are developed taking into account the division by strength and intensity specified in RD 52.27.724-2009 “Guidelines for short-term weather forecasts” general purpose", developed, approved and put into effect on March 1, 2010 by Roshydromet. Hydrometeorological phenomena are selected depending on the type of activity of a particular enterprise, organization or sector of the economy and belong to the types of specialized hydrometeorological services.* (data from the hydrometeorological center of the Russian Federation)

It's easy to get tired of the same weather day after day, but sudden changes can really shock people. Below are some of the rarest meteorological phenomena: Some of them are beautiful, others are deadly, but all of them, without exception, inspire awe in people.

10. Multi-colored snow

On a frosty morning in 2010, residents of Stavropol, Russia woke up to colorful snow lining their streets. People were stunned when they saw the light purple and brown snowdrifts. Other people who heard the story may have thought it was a hoax, but scientists who investigated the matter confirmed that it was a snowfall made up of snow of many colors.

It was not toxic, but experts warned against ingesting snow of any color as it was likely contaminated with dust carried over from Africa. The dust reached dizzying heights in upper layers atmosphere, where it mixed with ordinary snow clouds. This interaction caused beautifully colored snow to fall. This was not the first time something like this had happened - in 1912, black snow fell in Alaska and Canada. The black color was due to volcanic ash and rocks that were also mixed with snow clouds.

9. Derecho


In 2012, a huge and heavy storm, consisting of several thunderstorms and strong winds, left a trail of destruction throughout the Midwest and mid-Atlantic region. This terrifying type of storm is called a derecho, and in in this case The storm was upgraded to a "super derecho" due to its severity.

The main cause of the superstorm was the intense heat experienced in this area, combined with pulsations in jet stream. The state of Virginia suffered a massive power outage, cables snapping like twigs, trucks flipping on their sides as if they were made of cardboard. 13 people died.

Derechos are very rare in the mid-Atlantic region, occurring only once every four years or so. Another extremely destructive derecho occurred in the United States in 2009. The storm covered a distance of 1,600 kilometers in one day, leaving behind several dead and many more injured. During this storm, 45 terrible tornadoes struck the earth.

8. Snow storm


Residents east coast The United States was experiencing a normal snowstorm in 2011 when it suddenly witnessed flashes of lightning and rumbles of thunder that mixed with the snow. A snow storm was happening right before their eyes.

A snow storm mimics the internal processes of a normal thunderstorm by forming through upward motion humid air. This combination of low humidity air and colder air higher up causes lightning and thunderstorms. This is why snow thunderstorms occur so rarely, given that in the lower layer there is usually no warm temperature during snowfall.

Meteorologists noted that the appearance of a snow thunderstorm most likely means that heavy snowfall will occur. Researchers found that there is a more than 80 percent chance that snow at least 15 centimeters deep will fall within a 112-kilometer radius of a lightning flash during a blizzard.

7. Colorful solar storm


We are all familiar with the phenomenon northern lights, which usually appears as blue and green swirls in the sky. However, sometimes solar storms are so strong that they cause a kaleidoscope of colors to appear and can even be seen in regions where people have never seen them before. In 2012, one of these intense solar storms created a particularly beautiful glow over crater lake in Oregon. Scientists have suggested that two clouds of luminous particles are launched towards the Earth by sunspots larger than our planet in size. Intensity polar lights allowed people to see them from great distances, even to the states of Maryland and Wisconsin. In addition, they also put on a beautiful show in Canada on the way down from the Arctic.

6. Double tornado


Tornadoes occur every year all over the world, but double tornadoes occur only once every 10 to 20 years. When they appear, they cause enormous destruction. The town of Pilger, Nebraska knows first-hand the enormous damage these tornadoes can cause in a matter of minutes. A twin tornado that hit the city in 2014 killed a child and injured nineteen others.

There is some disagreement as to exactly how double tornadoes form. Some experts believe that the process of occlusion contributes to the formation of these vortices. Occlusion occurs when one tornado becomes surrounded by cold, moist air. When this "wrapped" tornado begins to weaken, it can lead to the formation of a second tornado. This usually occurs when there is a lot of energy present in the original storm.

Others argue that storms with multiple vortices or even individual supersells are responsible for the formation of double tornadoes. Whatever the cause, all experts agree that twin tornadoes are deadly and should promptly seek shelter.

5. Vortex Squall (Gustnado)


A whirlwind squall is the term used to describe a short-lived tornado that is completely isolated from the main thunderstorm from which standard tornadoes typically spawn. In 2012 heavy thunderstorm generated a swirling squall due to high-speed winds in southeastern Wisconsin. The rare occurrence stunned the local fire department, which rushed to the aid of people caught up in the storm.

A vortex squall is not as strong as a tornado and is formed when a rainstorm pulls down cold air from inside the storm. The cold air that is pushed down by the rain hits the ground hard and then spews out a gust of wind, which in turn becomes a vortex squall. A strong vortex squall usually forms when many cold gusts formed on the ground mix with hot air. Vortex squalls last only a few minutes, however, they are quite capable of causing serious damage in the surrounding area.

4. Inversion


Just after Thanksgiving in 2013, visitors to the Grand Canyon noticed something strange—the canyon was quickly filling with thick fog. Tourists were left in awe as fog rolled into the park and ended up forming what looked like a waterfall of clouds. This weather anomaly is known as an inversion.

An inversion is caused by cold air that sinks close to the ground while more warm air moves over him. The inversion at the Grand Canyon began when a storm passed through the area just before the holiday, causing the ground to freeze. When warmer air moved into the area, it formed beautiful phenomenon inversions. Park rangers have confirmed that smaller inversions are fairly common here, but larger ones that fill the entire canyon only occur once every ten years or so. This inversion lasted the whole day and the fog cleared only when it began to get dark.

3. Solar tsunami


2013 was good year for rare meteorological phenomena. In the middle of the year, two satellites recorded something unusual happening on the surface of the Sun. A tsunami rolled along its surface as a result of the release of matter into space.

The injection and subsequent solar tsunami gave scientists a deeper understanding of the dynamics of tsunamis, as well as how they occur on Earth. The Japanese Hindoe satellite and the Solar Dynamics Observatory play an important role in studying events that occur on the Sun. They both study its ultraviolet radiation to determine the exact conditions on the surface.

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Hindoe also collected enough data for experts to finally figure out why the solar corona is thousands of degrees hotter than its surface. It was during this study that scientists learned about shock waves following the ejection of matter. This incident was very similar to the movement of a tsunami on Earth after an earthquake occurred. Shock waves are very rare, making solar tsunamis also a rare phenomenon.

2. Superrefraction


Also in 2013, people living in northern Ohio woke up one morning and were stunned to discover that they could see all the way to the Canadian coastline. This is absolutely impossible in normal conditions because of how the Earth is curved. However, locals could see as far as Canada due to a rare natural phenomenon known as super-refraction, which bends light rays down toward the Earth's surface. The beams bend this way due to changes in air density. During this bending of light, distant objects can be easily seen because they are reflected in the light rays. Light from the sun bent downward so strongly over Lake Erie that refraction made the Canadian coastline visible more than 80 kilometers away.

1. Atmospheric blocking

Atmospheric blocking is quite possibly the rarest meteorological phenomenon on Earth, which is a good thing since it is also one of the most dangerous. It occurs when the system high pressure gets stuck and cannot move from one place to another. Depending on the type of system, this can either result in flooding or extremely hot and dry weather.

An example of atmospheric blocking is the 2003 European heat wave that killed 70,000 people. The anticyclone that was stuck in this case was very powerful and blocked any pressure release fronts. In 2010, 15,000 Russians died in a heat wave caused by another atmospheric blockage. And in 2004, atmospheric blocking in Alaska caused temperatures so high that glaciers began to melt and large wildfires began in the area. However, this doesn't always mean doom and gloom - another atmospheric blocking in 2004 saw positive effects in Missouri as temperatures remained pleasant and ultimately produced fantastic harvests.

Meteorological emergencies– these are dangerous natural processes and phenomena that arise in the atmosphere under the influence of various natural factors or their combinations, which have or may have a damaging effect on people, farm animals and plants, economic objects and the natural environment.

Meteorological emergencies include:

• meteorological phenomena associated with air movement in the atmosphere;
• meteorological phenomena associated with high and low temperatures;
• meteorological phenomena associated with precipitation;
• meteorological phenomena associated with ice deposition and wet snow adhesion on electrical wires;
• meteorological phenomena associated with the formation of ice on roads;
• fog.

Meteorological phenomena associated with the movement of air in the atmosphere include:

• strong wind– air movement relative to the earth’s surface with a speed or horizontal component exceeding 14 m/s;
• vortex – atmospheric education with rotational movement of air around a vertical or inclined axis;
• Hurricane– wind of destructive force and considerable duration, the speed of which exceeds 32 m/s. Hurricane Katrina began forming on August 23, 2005 in the Bahamas. The wind speed during the hurricane reached 280 km/h. On August 27, 2005, a hurricane passed over the Florida coast near Miami and turned towards the Gulf of Mexico. The heaviest damage was caused to New Orleans in Louisiana, where about 80% of the city was under water. As a result natural disaster 1836 people died;
• cyclone- an atmospheric disturbance with low air pressure and hurricane wind speeds that occurs in tropical latitudes and causes enormous destruction and loss of life. Local name tropical cyclone– typhoon;
• storm - long-lasting very strong winds with a speed of over 20 m/s, causing strong disturbances at sea and destruction on land;
• tornado - a strong small-scale atmospheric vortex with a diameter of up to 1000 m, in which air rotates at a speed of up to 100 m/s, which has great destructive power (Fig. 8.8). A tornado is the most dangerous natural phenomenon associated with the movement of air in the atmosphere;
• squall - sudden short-term wind force of up to 20–30 m/s and higher, accompanied by a change in its direction and associated with convective processes;
• dust storm– transfer large quantities dust or sand by strong winds, accompanied by deterioration of visibility, blowing out the top layer of soil along with seeds and young plants, falling asleep on crops and highways. During a dust storm, you should cover your face with a gauze bandage, a scarf, a piece of cloth, and your eyes with glasses.

Rice. 8.8.

Meteorological phenomena associated with high and low temperatures include:

• severe frost– this is a meteorological phenomenon when the expected and observed negative anomalies of average daily air temperatures in November - March range from -10 to -25 ° C or more for at least 5 days or the minimum air temperature is close to extreme values;
• heatwave- this is a meteorological phenomenon when the expected and observed positive anomalies of average daily air temperatures in May - August for at least 5 days are +27 ° C or more or the maximum air temperature is close to extreme values.

IN summer time a dangerous agrometeorological phenomenon – drought – may occur. Drought– this is a complex meteorological factors in the form of a prolonged lack of precipitation combined with high temperature and decreased air humidity, leading to disruption of the water balance of plants and causing their depression or death.

Severe frost and heat are dangerous to the life and health of people, negatively affect their ability to work, and cause damage to agriculture and industry. Fire danger also increases during such periods. Long and extreme low temperatures pose a particular danger to public utilities due to freezing of water supply pipes on the streets and indoors, which leads to a lack of water supply and water heating in people’s homes.

High and low temperatures may be accompanied by strong winds. IN winter time Blizzards are dangerous. Heavy snowstorm is the transfer of snow over the surface of the earth by the wind at a speed of more than 15 m/s and visibility of less than 500 m. A snowstorm is possible in combination with snowfall, which leads to poor visibility and skidding of transport highways.

In winter, the influence of the cooling force of the wind on the human body should be taken into account (Table 8.3).

During heavy snowstorms and low temperatures it is not advisable to move outside settlements. You can lose your bearings and freeze. You can only drive in a car on big roads and highways. When getting out of the car, you should not move away from it out of sight.

Table 8.3

The effect of the cooling force of wind on the human body

Wind force, m/s

Temperature, °C

Temperate zone

Increasing danger zone

Dangerous area

Meteorological phenomena associated with precipitation include the following.

Hail – precipitation, falling in the warm season in the form of particles of dense ice with a diameter of 5 mm to 15 cm, usually together with heavy rain during a thunderstorm. Large hail is considered to be ice particles with a diameter of more than 20 mm. Heavy hail is dangerous to the life and health of people; it can destroy crops and damage the roofs of buildings and vehicles.

Shower (heavy rain)– this is short-term precipitation of high intensity, usually in the form of rain (rain with snow). Heavy rain is considered to be a precipitation of 50 mm or more in 12 hours or 30 mm or more in 1 hour. Prolonged heavy rainfall is a precipitation of 100 mm or more in 2 days. Heavy rains can cause floods, street flooding, mudflows, and impede traffic.

Heavy snowfall - This is prolonged intense snowfall (20 mm of precipitation or more in 12 hours), leading to a significant deterioration in visibility and difficulty in traffic.

Meteorological phenomena associated with the formation of ice and the adhesion of wet snow on electric wires, pose a danger to the power supply, which can lead to broken wires and disruption of the power supply to populated areas and regions. Such cases happen in Russia, in particular in Black Sea coast Caucasus, Stavropol Territory, etc. Broken wires pose a danger to human life.

Ice is a layer of dense ice that forms on the earth’s surface and on objects when supercooled drops of rain or fog (melted and then re-frozen snow) freeze. Ice is dangerous for pedestrians and vehicles.

If the weather forecast calls for ice or ice, you should take steps to reduce the likelihood of injury by preparing low-slip shoes, attaching metal heels or foam rubber to the heels, and applying an adhesive plaster to the dry sole, or rubbing the sole of the shoe with sandpaper.

You should move carefully, slowly, stepping on the entire sole. In this case, the legs should be slightly relaxed and the hands should be free. If you slip, you should

crouch down to reduce the height of your fall. At the moment of falling, you need to group yourself and, by rolling, soften the blow to the ground.

Fog - meteorological phenomenon, an accumulation of condensation products in the form of drops or crystals suspended in the air directly above the surface of the earth, accompanied by a significant decrease in visibility. Heavy fog is considered to be fog with visibility less than 100 m. Due to heavy fog, car accidents can occur and planes cannot land at airports.

natural meteorological atmospheric

• - heavy rains. Most often (95-100% probability) they fall in the Carpathians and predetermine mudflows, avalanches and shifts;
• - strong blizzards, snowfalls. Blizzards are associated with the movement of cyclones from the south and southwest. Poor visibility during snowstorms and heavy snow drifts create many difficulties, both in operation different types transport, and in work on construction sites;
• - strong wind (with a maximum speed of over 25 m/s), squalls, tornadoes. Most often, such wind is observed in mountainous areas, as well as in the Donetsk, Volyn and Podolsk uplands;
• - fog is an accumulation of water droplets or ice crystals suspended in the ground layer of the atmosphere, which impairs horizontal visibility at a distance of up to 1 km. Based on intensity, fogs are classified as very strong (visibility is less than 50 m), strong (50-200 m), moderate (201-500 m) and weak (501-1000 m);
• - A thunderstorm is a complex atmospheric phenomenon that is accompanied by electrical discharges, significant precipitation and often hail. Thunderstorm belongs to hazardous phenomena, the action of which can cause significant damage to activities and even threaten human life;
• - Hail - rounded or irregular shape ice particles that fall mostly during the warm period of the year from powerful cumulonimbus clouds with significant vertical movement and high content moisture. Hail causes significant losses to agriculture: it damages crops, vineyards, fruit trees, on large areas. The amount of damage depends on the size of the hailstones, their density and the intensity of the fall;
• - A squall is a short-term sharp increase in wind speed, which forms in cumulonimbus clouds, is accompanied by a change in wind direction and is observed during thunderstorms and showers. During a squall, trees are broken, crops are destroyed, buildings are destroyed, and sometimes even human casualties are possible;
• - A tornado is a vortex of a complex structure with vertical axis, which descends from the lower limit of powerful cumulonimbus clouds to the earth's surface. In the form of a light or dark funnel, which rotates and is characterized by significant wind speeds, powerful downward and upward flows, a significant difference in atmospheric pressure, from the center of the funnel to the periphery, which together creates the extreme energy of a tornado;
• - A dust storm or black storm is a phenomenon that is caused by the transfer of large amounts of dust or sand by strong winds and is accompanied by reduced visibility. A dust storm occurs during dry weather and when wind speed increases to values ​​at which parts of dust or sand are blown out of the underlying surface.