All processes in nature are cyclical. At a certain time there is a change of seasons, each of which is beautiful in its own way and for a certain season its own characteristics are characteristic. natural phenomena. Some phenomena seem so simple and natural that we do not notice them and take them for granted, but, meanwhile, each natural phenomenon is unique, even the most familiar of them is subject to relevant laws nature.
Consider natural phenomena, common and rare, characteristic of our latitudes.
Dew. The air contains water vapor, which condenses as it falls to the ground. Dew appears on cool summer evenings and early mornings on the leaves and stems of plants. When the thermometer drops below zero, frost forms.
Rainbow- This is an optical natural phenomenon that occurs in the atmosphere as a result of the refraction of sunlight by raindrops. Rainbows can be observed during or immediately after a summer rain, when sunlight passes through the rain streams.
Thunderstorm represents electrical discharges that are collected in the layers of the atmosphere.
A thundercloud is charged with positive and negative particles. Lightning occurs due to the collision of clouds with the signs "-" and "+".
An electric field arises between the earth and the cloud, air ionization occurs. When the heat reaches its peak, a breakdown occurs and lightning strikes the ground.
sound waves at electrical discharges create an echo, i.e. peals of thunder.
Lightning comes in different types: linear, the most common, as well as rarer, pearl and ball. Fireball has the shape of a ball or oval. The phenomenon quickly arises and also quickly disappears. It is almost impossible to predict the trajectory of the fireball.
Pearl Lightning appear after the linear ones and have a rounded shape, accompanied by thunder.
Another wonderful and mysterious phenomenon, which can be observed almost all year round is meteoritic or star Rain. On a dark clear night, bright light rays line the sky. The intensity of the streams is different, depending on the season, and such stellar showers are repeated every year at about the same time, only the intensity and brightness are different. The most spectacular starfall can be observed on August 12 and the peak of Perseid activity.
Northern lights- a fascinating and very spectacular natural phenomenon.
On the territory of our country, the northern lights can be seen in almost all regions located near the Arctic Circle, from Murmansk to Chukotka.
The northern lights are a bright glow in the dark sky, which is formed due to the interaction of the upper atmosphere with the charged particles of the sun.
The more active the sun, the more likely the beginning of the northern lights. The spectacle is accompanied by a crash.
Halo. This phenomenon is scientifically substantiated and is not rare. Sometimes a bright circle of light can be observed in the sky, formed by the refraction of the rays of the sun in the ice crystals contained in the body of the cloud. In the immediate vicinity of the main circle, one can observe luminous circles of smaller diameter. The phenomenon of the halo looks very impressive.
Eclipse occurs at the moment when the glow of one object is blocked by another object.
Moon eclipse occurs when the Moon is in the cone-shaped zone of the shadow cast by the Earth.
Solar eclipse happens when the moon is between the place of observation and the sun and obscures it. Immediately before the eclipse, the Moon looks at the Earth with its unlit side and before the eclipse there is a new moon, the moon is not visible in the sky.
Natural phenomena are truly unique and are of great interest to researchers and amateurs. There are also dangerous phenomena, such as, for example, a volcanic eruption, a hurricane or a flood. They have a powerful destructive force, before which a person is helpless. Nature is fraught with a myriad of mysteries and questions, the answers to which will be given to future generations of scientists and researchers.
To natural hazards include natural phenomena that pose a threat to human life and health.
All natural hazards are subject to the following patterns:
each type of hazard is characterized by a certain spatial confinement;
the greater the intensity (power) of a dangerous phenomenon, the less often it happens;
each type of danger is preceded by certain specific signs (harbingers);
manifestation of any natural hazard can be predicted;
in most cases, passive and active protective measures can be provided.
The manifestation of natural hazards is significantly influenced by anthropogenic impact: according to international statistics, the origin of about 80% of modern landslides is associated with human activities; as a result of deforestation, the activity of mudflows increases, the flood flow increases; large-scale use of natural resources has led to tangible manifestations of the global environmental crisis.
The study of the causes and mechanisms of natural hazards makes it possible to predict them, which is the most important prerequisite for effective protection. Protection from natural hazards can be active (construction of engineering structures, intervention (Latin interventionio - intervention) in the mechanism of the phenomenon, mobilization of natural resources, reconstruction of natural objects, etc.) and passive (use of shelters, evacuation). In most cases, active and passive methods are combined.
By localization, natural hazards are conditionally divided into 4 groups: lithospheric (earthquakes, volcanoes, landslides), hydrospheric (floods, tsunamis, storms), atmospheric (hurricanes, storms, tornadoes, hail), space (asteroids, planets, radiation, magnetic storms) .
1. Lithospheric hazards
Earthquakes. The upper mantle together with the earth's crust form the lithosphere. It is in the mantle (temperature 2000-2500 ° C) that tectonic (from the Greek tektonikos - related to construction) processes occur that cause earthquakes.
earthquakes- these are tremors and vibrations of the earth's surface resulting from sudden displacements and breaks in earth's crust or the upper part of the mantle and transmitted over long distances in the form of elastic vibrations. Earthquakes occur as a series of shocks that include foreshocks, mainshocks, and aftershocks. The main shock is characterized by the greatest force, its duration, as a rule, is several seconds. According to psychiatrists and psychologists, people under the influence of aftershocks, shackled by fear, do nothing instead of looking for a safe place and defending themselves.
The source of an earthquake is a certain volume in the thickness of the Earth, within which energy is released. The center of the focus is a conditional point called hypocenter. The projection of the hypocenter onto the Earth's surface is called epicenter. Around him there is the greatest destruction. Every year, hundreds of thousands of earthquakes are recorded on the globe, most of which are weak and people do not notice them. The strength of an earthquake is estimated by:
on the scale of intensity, which characterizes the scale of destruction on the surface of the Earth;
on the magnitude scale, which is the energy characteristic of an earthquake.
The international intensity scale MSK-64, adopted in Russia, is calculated using a 12-point system.
International Earthquake Intensity Scale
|
Strength in points |
Intensity |
Effects |
|
Imperceptible ground shaking |
Recorded only by seismic instruments |
|
|
Very weak |
Felt by individuals at rest |
|
|
Felt by only a small part of the population |
||
|
Moderate |
Light rattling of glass, creaking of doors, walls |
|
|
Pretty strong |
Shaking of buildings, vibrations of equipment, cracks in window panes and plaster |
|
|
Partial collapse of internal walls, breaks in wire communications, failures in the operation of sensitive equipment, the occurrence of individual fires |
||
|
Very strong |
Damage, cracks in stone buildings and structures, breaks in power lines. Wooden and anti-seismic buildings are preserved |
|
|
destructive |
Cracks on steep slopes and damp soils. Loose equipment shifts and is damaged. Old buildings are destroyed, the rest are badly damaged. The fall of individual power transmission towers, communication lines, ground overpasses |
|
|
devastating |
Strong destruction of stone buildings and structures. Curvature of wooden buildings. Partial damage hydraulic structures |
|
|
Destroying |
Strong destruction of all buildings and structures. Cracks in the soil up to one meter wide are possible. Destruction of transport routes. Slopes, landslides |
|
|
catastrophic |
Complete destruction of buildings and structures, bending and twisting of railway rails. Widespread cracks on the surface of the earth, landslides and landslides. Underground collapses |
|
|
Absolute or strong catastrophic |
Solid landslides, collapses, huge cracks on the surface of the earth. Deviations and changes in the flow of rivers, the formation of lakes, waterfalls. Partial change in terrain |
Richter scale- magnitude scale, based on the assessment of the energy of seismic waves that occur during earthquakes and are recorded by seismographs. The magnitude of earthquakes on the Richter scale cannot exceed 9.5. Magnitude earthquakes - a conditional value that characterizes the total energy of elastic vibrations caused by an earthquake
When an earthquake occurs, its magnitude first becomes known, which is determined by seismograms, and the intensity is determined some time later, after receiving information about the consequences.
|
Magnitude |
Intensity |
Magnitude |
Intensity |
According to statistics, an earthquake with a magnitude of 8 occurs every 102 years.
Earthquakes are distributed over the earth's surface very unevenly. The analysis of seismic and geographic data makes it possible to outline the areas where an earthquake should be expected. This is the essence of seismic zoning. Seismic zoning map- This official document which design organizations should be guided by.
Earthquakes are considered dangerous for buildings and structures, the intensity of which is 7 points or more. The strongest earthquake of the twentieth century. occurred on July 28, 1976 near the city of Tangshan in China. According to some data, 242 thousand people died, according to others - more than half a million, the damage amounted to more than $ 2 billion.
There are two groups of anti-seismic measures: 1) preventive, preventive measures carried out before a possible earthquake; 2) activities carried out during and after the earthquake, that is, actions in emergency situations.
The first group includes the study of the nature of earthquakes, the disclosure of its mechanism, the identification of precursors. The harbingers of earthquakes can be the following anomalous phenomena: the disappearance of constant weak earthquakes; changes in the electrical and magnetic properties of rocks; drop in the level of groundwater, a decrease in their temperature and a change in the chemical composition, the release of methane from the earth's crust.
The effectiveness of actions in earthquake conditions depends on the level of organization of emergency rescue operations, the effectiveness of the warning system and the level of education of the population.
At the first shock of an earthquake, it is necessary to urgently leave the building (there are 10-15 seconds left) or take the safest place inside the building: under the doorway, in the openings of the main internal walls or in the corners of these walls.
Volcanic eruptions.Volcanoes are geological formations on the surface of the earth's crust, where magma comes to the surface, forming lava, volcanic gases and stones. These products of the eruption are ejected to a height of 1 to 5 km and are transported over long distances. Magma (from the Greek. magma- thick ointment) is a molten mass of predominantly silicate composition, formed in the deep zones of the Earth.
Volcanoes are divided into active, dormant and extinct.
To sleeping Volcanoes are those whose eruptions are not known, but they have retained their shape and local earthquakes occur under them.
Extinct are volcanoes without any volcanic activity.
In Russia, Kamchatka is exposed to the danger of volcanic eruptions, Kurile Islands, Sakhalin island. The basis of the eruption forecast is seismic tremors that characterize the beginning of the eruption.
The main dangers are lava fountains, hot lava flows, hot gases. Volcanic explosions can also initiate landslides, collapses, avalanches, and tsunamis on the seas and oceans. Formed during the Krakatoa eruption in 1883 sea wave a height of about 20 m covered those around the island, which led to the death of 36 thousand people.
The most reliable way to protect yourself from a volcanic eruption is to choose a place of residence at the maximum distance from active volcanoes.
Snow avalanches. Avalanche- This snowfall, a mass of snow that falls or slides down the mountain slopes under the influence of some kind of influence and entrains new masses of snow on its way.
The danger of an avalanche lies in the high kinetic energy of the avalanche mass, which has tremendous destructive power. Avalanches form on treeless slopes with a steepness of 15° or more. The optimal conditions for the formation of avalanches occur on slopes of 30...40°. With a steepness of more than 50°, the snow crumbles to the foot of the slope, and avalanches do not have time to form. Avalanche speed can reach 125 m/s, averaging 20-60 m/s. It is not possible to accurately predict the timing of an avalanche.
Anti-avalanche preventive measures are divided into 2 groups: passive and active.
Passive Methods consist in the use of supporting structures, dams, avalanche cutters, snow shields, planting and reforestation.
Active Methods consist in artificially provoking an avalanche. For this, directional explosions are organized, strong sound sources are used.
The classification of natural includes the main types of emergency events of natural origin.
|
Type of natural emergency |
Dangerous phenomena |
|
Cosmogenic |
Falling asteroids on the Earth, collision of the Earth with comets, comet showers, collision of the Earth with meteorites and bolide streams, magnetic storms |
|
Geophysical |
Earthquakes, volcanic eruptions |
|
Geological (exogenous geological) |
Landslides, mudflows, landslides, screes, avalanches, slope washout, subsidence of loess rocks, subsidence (collapses) of the earth's surface as a result of karst, abrasion, erosion, kurums, dust storms |
|
Meteorological |
Storms (9-11 points), hurricanes (12-15 points), tornadoes (tornadoes), squalls, vertical whirlwinds (streams) |
|
Hydrometeorological |
big city, heavy rain(rainstorm), heavy snow, heavy ice, hard frost, heavy blizzard, intense heat, heavy fog, drought, dry wind, frost |
|
Marine hydrological |
Tropical cyclones (typhoons), tsunamis, strong waves (5 points or more), strong sea level fluctuations, strong draft in ports, early ice cover or fast ice, ice pressure, intense ice drift, impassable (hard-to-pass ice), icing of ships, separation coastal ice |
|
Hydrological |
High water levels, floods, rain floods, traffic jams and ice dams, wind surges, low levels water, early freezing and premature appearance of ice on navigable reservoirs and rivers, rising groundwater levels (flooding) |
|
natural fires |
Forest fires, fires of steppe and grain massifs, peat fires, underground fires of fossil fuels |
An analysis of the development of natural catastrophic phenomena on Earth shows that, despite scientific and technological progress, the protection of people and the technosphere from natural hazards does not increase. The number of victims in the world from destructive natural phenomena in recent years has been increasing annually by 4.3%, and those affected by 8.6%. Economic losses are growing at an average of 6% per year. Currently, there is an understanding in the world that natural disasters are global problem, which is a source of the deepest humanitarian shocks and is one of the most important factors determining the sustainable development of the economy. The main reasons for the preservation and aggravation of natural hazards may be the growth of anthropogenic impact on the environment; irrational placement of objects of the economy; resettlement of people in areas of potential natural hazard; insufficient efficiency and underdevelopment of environmental monitoring systems; weakening government systems observation of natural processes and phenomena; the absence or poor condition of hydraulic engineering, anti-landslide, anti-mudflow and other protective engineering structures, as well as protective forest plantations; insufficient volumes and low rates of earthquake-resistant construction, strengthening of buildings and structures in earthquake-prone areas; absence or insufficiency of inventories of potentially dangerous areas (regularly flooded, especially seismic, mudflow, avalanche, landslide, tsunami, etc.).
More than 30 natural hazards and processes occur on the territory of Russia, among which the most destructive are floods, storm winds, downpours, hurricanes, tornadoes, earthquakes, forest fires, landslides, mudflows, snow avalanches. Most of the social and economic losses are associated with the destruction of buildings and structures due to insufficient reliability and protection from natural hazards. The most frequent on the territory of Russia are natural catastrophic atmospheric phenomena - storms, hurricanes, tornadoes, squalls (28%), followed by earthquakes (24%) and floods (19%). Dangerous geological processes, such as landslides and collapses account for 4%. The remaining natural disasters, among which forest fires have the highest frequency, total 25%. The total annual economic damage from the development of the 19 most dangerous processes in urban areas in Russia is 10-12 billion rubles. in year.
Of the geophysical extreme events, earthquakes are one of the most powerful, terrible and destructive natural phenomena. They arise suddenly, it is extremely difficult, and most often impossible, to predict the time and place of their appearance, and even more so to prevent their development. In Russia, zones of increased seismic hazard occupy about 40% of the total area, including 9% of the territory belong to 8-9-point zones. More than 20 million people (14% of the country's population) live in seismically active zones.
There are 330 settlements within seismically dangerous regions of Russia, including 103 cities (Vladikavkaz, Irkutsk, Ulan-Ude, Petropavlovsk-Kamchatsky, etc.). Most dangerous consequences earthquakes are the destruction of buildings and structures; fires; releases of radioactive and emergency chemical hazardous substances due to the destruction (damage) of radiation and chemically hazardous objects; transport accidents and disasters; defeat and loss of life.
A striking example of the socio-economic consequences of strong seismic events is the Spitak earthquake in Northern Armenia, which occurred on December 7, 1988. This earthquake (magnitude 7.0) affected 21 cities and 342 villages; 277 schools and 250 healthcare facilities were destroyed or were in emergency condition; stopped functioning more than 170 industrial enterprises; about 25 thousand people died, 19 thousand received varying degrees mutilation and injury. The total economic losses amounted to $14 billion.
Of the geological emergency events, the most dangerous due to the massive nature of the distribution are landslides and mudflows. The development of landslides is associated with displacements of large masses rocks on slopes under the influence of gravitational forces. Precipitation and earthquakes contribute to the formation of landslides. AT Russian Federation 6 to 15 emergencies associated with the development of landslides are created annually. Opol-zni are widespread in the Volga region, Transbaikalia, the Caucasus and Ciscaucasia, Sakhalin and other regions. Urbanized areas are especially hard hit: 725 Russian cities are subject to landslides. Mudflows are powerful streams, saturated hard materials descending the mountain valleys great speed. Mudflows are formed with rainfall in the mountains, intensive melting of snow and glaciers, as well as breakthrough of dammed lakes. Mudflow processes are manifested in 8% of the territory of Russia and develop in the mountainous regions of the North Caucasus, in Kamchatka, the Northern Urals and Kola Peninsula. Under the direct threat of mudflows in Russia there are 13 cities and 42 more cities are located in potentially mudflow-prone areas. The unexpected nature of the development of landslides and mudflows often leads to the complete destruction of buildings and structures, accompanied by casualties and large material losses. Of the hydrological extreme events, floods can be one of the most common and dangerous natural phenomena. In Russia, floods rank first among natural Disasters in terms of frequency, distribution area, material damage and second place after earthquakes in terms of the number of victims and specific material damage (damage per unit of affected area). One severe flood covers an area of the river basin of about 200 thousand km2. On average, up to 20 cities are flooded every year and up to 1 million inhabitants are affected, and in 20 years almost the entire territory of the country is covered by serious floods.
On the territory of Russia, from 40 to 68 crisis floods occur annually. The threat of floods exists for 700 cities and tens of thousands of settlements, a large number of economic facilities.
Floods are associated with significant material losses every year. In recent years, two major floods have occurred in Yakutia on the river. Lena. In 1998, 172 settlements were flooded here, 160 bridges, 133 dams, 760 km of roads were destroyed. The total damage amounted to 1.3 billion rubles.
Even more devastating was the flood in 2001. During this flood, the water in the river. Lene rose to 17 m and flooded 10 administrative districts of Yakutia. Lensk was completely flooded. About 10,000 houses were under water, about 700 agricultural and more than 4,000 industrial facilities, 43,000 people were resettled. The total economic damage amounted to 5.9 billion rubles.
A significant role in increasing the frequency and destructive power of floods is played by deforestation, irrational management Agriculture and economic development of floodplains. The formation of floods can be caused by improper implementation of flood protection measures, leading to the breakthrough of dams; destruction of artificial dams; emergency discharges of reservoirs. The aggravation of the problem of floods in Russia is also associated with the progressive aging of fixed assets of the water sector, the placement of economic facilities and housing in flood-prone areas. In this regard, the development and implementation of effective flood prevention and protection measures may be an urgent task.
Among the atmospheric hazardous processes occurring on the territory of Russia, the most destructive are hurricanes, cyclones, hail, tornadoes, heavy rains, snowfalls.
Traditional in Russia is such a disaster as a forest fire. Every year in the country there are from 10 to 30 thousand. forest fires on an area from 0.5 to 2 million hectares.
Preliminary forecast of the main dangers and threats for Russia in early XXI in. indicates that before 2010 destructive earthquakes may occur in three seismological regions: Kamchatka - Kuril Islands, Baikal and North Caucasus. One devastating earthquake can occur in each of these regions. Without taking preventive measures, tens of thousands of people's lives could be lost and about $10 billion in damage. Today, the occurrence of 3-5 man-made earthquakes, one devastating tsunami on the Pacific coast, one or two catastrophic floods, as well as an increase in the number of forest and peat fires cannot be ruled out.
Natural phenomena are ordinary, sometimes even supernatural climatic and meteorological events that occur naturally in all corners of the planet. It can be snow or rain familiar from childhood, or it can be incredible destructive or earthquakes. If such events take place away from a person and do not cause him material damage, they are considered unimportant. No one will draw attention to this. Otherwise, dangerous natural phenomena are considered by mankind as natural disasters.
Research and observation
People began to study characteristic natural phenomena in ancient times. However, it was possible to systematize these observations only in the 17th century, and even a separate section of science (natural science) was formed that studies these events. However, despite many scientific discoveries, and to this day, some natural phenomena and processes remain poorly understood. Most often, we see the consequence of an event, and we can only guess about the root causes and build various theories. Researchers in many countries are working on forecasting the occurrence, and most importantly, preventing their possible occurrence or at least reducing the damage caused by natural phenomena. And yet, despite all the destructive power of such processes, a person always remains a person and strives to find something beautiful, sublime in this. What natural phenomenon is the most fascinating? They can be listed for a long time, but, probably, it should be noted such as a volcanic eruption, a tornado, a tsunami - they are all beautiful, despite the destruction and chaos that remain after them.
Weather phenomena of nature
Natural phenomena characterize the weather with its seasonal changes. Each season has its own set of events. So, for example, in the spring the following snowmelt, flood, thunderstorms, clouds, wind, rains are observed. In summer, the sun gives the planet an abundance of heat, natural processes at this time are most favorable: clouds, warm wind, rain and, of course, a rainbow; but can also be severe: thunderstorms, hail. In autumn they change, the temperature drops, the days become cloudy, with rain. During this period, the following phenomena prevail: fogs, leaf fall, hoarfrost, first snow. In winter, the plant world falls asleep, some animals hibernate. The most frequent natural phenomena are: freezing, snowstorm, blizzard, snow, on the windows appear
All these events are ordinary for us, we have not paid attention to them for a long time. Now let's look at the processes that remind humanity that it is not the crown of all, and the planet Earth just sheltered it for a while.
Dangerous natural phenomena
These are extreme and severe climatic and meteorological processes that occur in all parts of the world, but some regions are considered more vulnerable to certain types of events than others. Hazardous natural phenomena become disasters when infrastructure is destroyed and people die. These losses represent major obstacles to human development. It is practically impossible to prevent such cataclysms; all that remains is timely forecasting of events in order to prevent casualties and material damage.
However, the difficulty lies in the fact that dangerous natural phenomena can take place on different scales and in different time. In fact, each of them is unique in its own way, and therefore it is very difficult to predict it. For example, flash floods and tornadoes are destructive but short-lived events affecting relatively small areas. Other dangerous disasters, such as droughts, can develop very slowly, but affect entire continents and entire populations. Such disasters last for several months, and sometimes even years. In order to monitor and predict these events, some national hydrological and meteorological services and special specialized centers are entrusted with the task of studying dangerous geophysical phenomena. This includes volcanic eruptions, airborne ash, tsunamis, radioactive, biological, chemical pollution, etc.
Now let's take a closer look at some natural phenomena.
Drought
The main reason for this cataclysm is the lack of rainfall. Drought is very different from other natural disasters in its slow development, often hidden by various factors. There are even recorded cases in world history when this disaster lasted for many years. Drought often has devastating consequences: first, water sources (streams, rivers, lakes, springs) dry up, many crops stop growing, then animals die, widespread realities become poor health and malnutrition.
Tropical cyclones
These natural phenomena are areas of very low atmospheric pressure over subtropical and tropical waters, forming a colossal rotating system of thunderstorms and winds hundreds (sometimes thousands) of kilometers across. The speed of surface winds in the zone of a tropical cyclone can reach two hundred kilometers per hour or even more. The interaction of low pressure and wind-driven waves often results in a coastal storm surge - a huge volume of water washed ashore with tremendous force and high speed, which washes everything in its path.
Air pollution
These natural phenomena arise as a result of the accumulation in the air of harmful gases or particles of substances resulting from cataclysms (volcanic eruptions, fires) and human activities (the work of industrial enterprises, vehicles, etc.). Haze and smoke come from fires on undeveloped lands and forest areas, as well as burning the remains of crops and logging; in addition, due to the formation of volcanic ash. These atmospheric pollutants have very serious consequences for the human body. As a result of such cataclysms, visibility is reduced, there are interruptions in the operation of road and air transport.
desert locust
Such natural phenomena cause serious damage in Asia, the Middle East, Africa and the southern part of the European continent. When ecological and weather conditions favor the reproduction of these insects, they tend to concentrate in small areas. However, with an increase in the number of locusts, it ceases to be an individual creature and turns into a single living organism. From small groups, huge flocks are formed, moving in search of food. The length of such a jamb can reach tens of kilometers. In a day, he can cover distances of up to two hundred kilometers, sweeping away all vegetation in his path. So, one ton of locusts (this is a small part of the flock) can eat as much food per day as ten elephants or 2500 people eat. These insects pose a threat to millions of pastoralists and farmers living in vulnerable environmental conditions.
Flash floods and flash floods
Data can occur anywhere after heavy rainfall. Any flood plains are vulnerable to flooding, and severe storms cause flash floods. In addition, flash floods are sometimes even observed after periods of drought, when very heavy rains fall on a hard and dry surface through which the water flow cannot seep into the ground. These natural events are characterized by a wide variety of types: from violent small floods to a powerful layer of water that covers vast areas. They can be caused by tornadoes, severe thunderstorms, monsoons, extratropical and tropical cyclones (their strength can be increased by exposure to warm El Niño currents), melting snow and ice jams. In coastal areas, storm surges often result in flooding as a result of tsunamis, cyclones or rising river levels due to unusually high tides. The reason for the flooding of vast territories below the barrier dams is often the flood on the rivers, which is caused by melting snow.
Other natural hazards
1. Debris (mud) flow or landslide.
5. Lightning.
6. Extreme temperatures.
7. Tornado.
10. Fires on undeveloped lands or in forests.
11. Heavy snow and rain.
12. Strong winds.
Grishin Denis
Natural disasters have threatened the inhabitants of our planet since the beginning of civilization. Somewhere more, elsewhere less. There is no 100% security anywhere. Natural disasters can cause enormous damage. In recent years, the number of earthquakes, floods, landslides and other natural disasters has been constantly increasing. In my essay, I want to consider dangerous natural processes in Russia.
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NIZHNY NOVGOROD CITY ADMINISTRATION
Municipal budgetary educational institution
average comprehensive school № 148
Scientific Society of Students
Dangerous natural phenomena in Russia
Completed by: Grishin Denis,
6th grade student
Supervisor:
Sinyagina Marina Evgenievna,
geography teacher
Nizhny Novgorod
27.12.2011
PLAN
Page
Introduction
Chapter 1. Natural Hazards ( emergencies natural character).
1.1. The concept of emergency situations.
1.2 Natural disasters of a geographical nature.
1.3 Natural disasters of a meteorological nature.
1.4 Natural disasters of a hydrological nature.
1.5. Natural fires.
Chapter 2. Natural disasters in the Nizhny Novgorod region.
Chapter 3. Measures to combat natural disasters.
Conclusion
Literature
Applications
Introduction
In my essay, I want to consider dangerous natural processes.
Natural disasters have threatened the inhabitants of our planet since the beginning of civilization. Somewhere more, elsewhere less. There is no 100% security anywhere. Natural disasters can cause enormous damage.
Natural emergencies (natural disasters) have been on the rise in recent years. Volcanoes are becoming more active (Kamchatka), earthquakes are becoming more frequent (Kamchatka, Sakhalin, the Kuriles, Transbaikalia, the North Caucasus), and their destructive power is increasing. Floods have become almost regular (Far East, Caspian lowland, Southern Urals, Siberia), landslides are not uncommon along rivers and in mountainous areas. Ice, snowdrifts, storms, hurricanes and tornadoes visit Russia every year.
Unfortunately, in the zones of periodic flooding, the construction of multi-storey buildings continues, which increases the concentration of the population, underground communications are being laid, and dangerous industries are operating. All this leads to the fact that the usualfloods in these places, causing more and more catastrophic consequences.
In recent years, the number of earthquakes, floods, landslides and other natural disasters has been constantly increasing.
The purpose of my essay is to study natural emergencies.
The task of my work is the study of dangerous natural processes (natural emergencies) and measures of protection against natural disasters.
- The concept of natural emergencies
1.1.Natural emergencies -the situation in a certain territory or water area as a result of the occurrence of a source of natural emergencies that may or will entail human casualties, damage to human health or the environment natural environment, significant losses and violation of the living conditions of people.
Natural emergencies are distinguished by the nature of the source and scale.
Natural emergencies themselves are very diverse. Therefore, based on the causes (conditions) of occurrence, they are divided into groups:
1) dangerous geophysical phenomena;
2) dangerous geological phenomena;
3) dangerous meteorological phenomena;
4) marine dangerous hydrometeorological phenomena;
5) dangerous hydrological phenomena;
6) natural fires.
Below I want to take a closer look at these types of natural emergencies.
1.2. Natural disasters of a geophysical nature
Natural disasters associated with geological natural phenomena are divided into disasters caused by earthquakes and volcanic eruptions.
EARTHQUAKE - these are tremors and vibrations of the earth's surface, caused mainly by geophysical causes.
Complex processes are constantly taking place in the bowels of the earth. Under the action of deep tectonic forces, stresses arise, the layers of earth rocks are deformed, compressed into folds and, with the onset of critical overloads, they are displaced and torn, forming faults in the earth's crust. The gap is made by an instantaneous shock or a series of shocks that have the nature of a blow. During an earthquake, the energy accumulated in the depths is discharged. The energy released at depth is transmitted through elastic waves in the thickness of the earth's crust and reaches the surface of the Earth, where destruction occurs.
Two main seismic belts are known: the Mediterranean-Asian and the Pacific.
The main parameters characterizing an earthquake are their intensity and focus depth. The intensity of the manifestation of an earthquake on the surface of the Earth is estimated in points (see Fig. Table 1 in the Appendices).
Earthquakes are also classified according to the reason they occur. They can arise as a result of tectonic and volcanic manifestations, landslides (rock bursts, landslides) and, finally, as a result of human activity (filling reservoirs, pumping water into wells).
Of considerable interest is the classification of earthquakes not only by magnitude, but also by number (recurrence frequency) during the year on our planet.
Volcanic activity
arises as a result of constant active processes occurring in the depths of the Earth. After all, the inside is constantly in a heated state. During tectonic processes, cracks form in the earth's crust. Magma rushes along them to the surface. The process is accompanied by the release of water vapor and gases, which create enormous pressure, removing obstacles in their path. When reaching the surface, part of the magma turns into slag, and the other part pours out in the form of lava. From the vapors and gases released into the atmosphere, volcanic rocks called tephra are deposited on the ground.
According to the degree of activity, volcanoes are classified into active, dormant and extinct. The active ones include those that erupted in historical time. Extinct, on the contrary, did not erupt. Dormers are characterized by the fact that they periodically manifest themselves, but it does not come to an eruption.
Most dangerous phenomena that accompany volcanic eruptions are lava flows, tephra fallout, volcanic mudflows, volcanic floods, scorching volcanic clouds, and volcanic gases.
lava flows - These are molten rocks with a temperature of 900 - 1000 °. The flow rate depends on the slope of the cone of the volcano, the degree of viscosity of the lava and its amount. The speed range is quite wide: from a few centimeters to several kilometers per hour. In some and most dangerous cases, it reaches 100 km, but most often does not exceed 1 km / h.
Tephra is made up of fragments of hardened lava. The largest ones are called volcanic bombs, the smaller ones are called volcanic sand, and the smallest ones are called ash.
mud streams - these are powerful layers of ash on the slopes of the volcano, which are in an unstable position. When new portions of ash fall on them, they slide down the slope
Volcanic floods. When glaciers melt during eruptions, it can very quickly form great amount water, which leads to floods.
A scorching volcanic cloud is a mixture of hot gases and tephra. Damage it is due to the emergence shock wave (strong wind), propagating at speeds up to 40 km/h, and a shaft of heat with temperatures up to 1000°.
Volcanic gases. The eruption is always accompanied by the release of gases mixed with water vapor - a mixture of sulfur and sulfur oxides, hydrogen sulfide, hydrochloric and hydrofluoric acids in a gaseous state, as well as carbon dioxide and carbon monoxide in high concentrations, deadly to humans.
Classification of volcanoesproduced according to the conditions of their occurrence and the nature of the activity. On the first basis, four types are distinguished.
1) Volcanoes in subduction zones or zones of subduction of the oceanic plate under the continental one. Due to thermal concentration in the bowels.
2) Volcanoes in rift zones. They arise in connection with the weakening of the earth's crust and the bulging of the boundary between the crust and mantle of the earth. The formation of volcanoes here is associated with tectonic phenomena.
3) Volcanoes in zones of large faults. There are ruptures (faults) in many places in the earth's crust. There is a slow accumulation of tectonic forces that can turn into a sudden seismic explosion with volcanic manifestations.
4) Volcanoes of "hot spots" zones. In some areas under ocean floor"hot spots" are formed in the earth's crust, where a particularly high thermal energy. In these places, rocks melt and come to the surface in the form of basalt lava.
According to the nature of activity, volcanoes are divided into five types (see Fig. Table 2)
1.3. Natural disasters of a geological nature
Natural disasters of a geological nature include landslides, mudflows, snow avalanches, landslides, subsidence of the earth's surface as a result of karst phenomena.
Landslides - this is a sliding displacement of masses of rocks down the slope under the influence of gravity. They are formed in various rocks as a result of a violation of their balance or a weakening of strength. Caused by both natural and artificial (anthropogenic) causes. The natural ones include: an increase in the steepness of the slopes, washing away their foundations with sea and river waters, seismic shocks. Artificial are the destruction of slopes by road cuts, excessive removal of soil, deforestation, unreasonable farming on the slopes. According to international statistics, up to 80% of modern landslides are associated with human activities. they are at any time of the year, but mostly in the spring and summer.
Landslides are classifiedon the scale of the phenomenon, the speed of movement and activity, the mechanism of the process, the power and place of formation.
Landslides are classified according to their scale into large, medium and small scale.
Large ones are caused, as a rule, by natural causes and are formed along the slopes for hundreds of meters. Their thickness reaches 10 - 20 or more meters. The landslide body often retains its solidity.
Medium and small scale are smaller and are characteristic of anthropogenic processes.
The scale is often characterized by the area involved in the process. The speed of movement is very different.
By activity, landslides are divided into active and inactive. The main factors here are the rocks of the slopes and the presence of moisture. Depending on the amount of moisture, they are divided into dry, slightly wet, wet and very wet.
According to the mechanism of the process, they are divided into: shear landslides, extrusion, viscoplastic, hydrodynamic removal, sudden liquefaction. Often have signs of a combined mechanism.
According to the place of formation, they are divided into mountain, underwater, adjacent and artificial earth structures (pits, channels, rock dumps).
Mudflow (mudflow)
A turbulent mud or mud-stone stream, consisting of a mixture of water and rock fragments, suddenly arising in small basins mountain rivers. It is characterized by a sharp rise in the water level, wave movement, a short duration of action (on average from one to three hours), and a significant erosive-accumulative destructive effect.
The immediate causes of graying are showers, intense snowmelt, breakthrough of reservoirs, less often earthquakes, volcanic eruptions.
All mudflows are divided into three types according to the mechanism of origin: erosion, breakthrough and landslide-landslide.
In the case of erosion, the water flow is first saturated with clastic material due to flushing and erosion of the adjacent soil, and then a mudflow wave is already formed.
During a landslide, the mass breaks down to saturated rocks (including snow and ice). The saturation of the flow in this case is close to the maximum.
In recent years, technogenic factors have been added to the natural causes of the formation of mudflows: violation of the rules and norms of the work of mining enterprises, explosions during the laying of roads and the construction of other structures, logging, improper agricultural work and violation of the soil and vegetation cover.
When moving, mudflow is a continuous stream of mud, stones and water. On the basis of the main factors in the occurrence of mudflows are classified as follows;
Zonal manifestation. The main factor in the formation is climatic conditions (precipitation). They are zonal. The descent occurs systematically. The paths of movement are relatively constant;
regional manifestation. The main factor of formation is geological processes. The descent occurs episodically, and the paths of movement are inconsistent;
Anthropogenic. This is the result economic activity person. Occur where the greatest load on the mountain landscape. New mudflow basins are being formed. The gathering is episodic.
snow avalanches - snow masses falling from the slopes of the mountains under the influence of gravity.
Snow accumulating on mountain slopes, under the influence of gravity and weakening of structural bonds within the snow mass, slides or falls off the slope. Having started its movement, it quickly picks up speed, capturing new snow masses, stones and other objects along the way. The movement continues to more gentle sections or the bottom of the valley, where it slows down and stops.
The formation of avalanches occurs within the avalanche focus. An avalanche center is a section of a slope and its foot, within which an avalanche moves. Each focus consists of 3 zones: origin (avalanche collection), transit (tray), avalanche stop (removal cone).
Avalanche-forming factors include: the height of old snow, the condition of the underlying surface, the growth of freshly fallen snow, snow density, snowfall intensity, subsidence snow cover, snowstorm redistribution of snow cover, air temperature and snow cover.
The release range is important for assessing the possibility of hitting objects located in an avalanche hazardous areas Oh. Distinguish between the maximum range of the release and the most probable, or long-term average. The most probable range of release is determined directly on the ground. It is evaluated if it is necessary to place structures in the avalanche area on a long period. It coincides with the boundary of the avalanche source fan.
The frequency of avalanches is an important temporal characteristic of avalanche activity. Distinguish between the average long-term and intra-annual recurrence of the descent. The density of avalanche snow is one of the most important physical parameters, which determines the impact force of the snow mass, labor costs for its clearing or the ability to move along it.
How are they classified?
According to the nature of movement and depending on the structure of the avalanche source, the following three types are distinguished: trough (moves along a specific runoff channel or avalanche chute), wasp (snow landslide, does not have a specific runoff channel and slides across the entire width of the site), jumping (arises from trough where there are sheer walls or sections with a sharply increasing steepness in the drain channel).
According to the degree of repetition, they are divided into two classes - systematic and sporadic. Systematic descend every year or once every 2-3 years. Sporadic - 1-2 times in 100 years. It is rather difficult to determine their place in advance.
1.4. Natural disasters of a meteorological nature
All of them are divided into disasters caused by:
blown by the wind including a storm, a hurricane, a tornado (at a speed of 25 m/s or more, for the Arctic and Far Eastern seas - 30 m/s or more);
heavy rain (with precipitation of 50 mm or more for 12 hours or less, and in mountainous, mudflow and rainy areas - 30 mm or more for 12 hours or less);
large hail (with a hailstone diameter of 20 mm or more);
Heavy snowfall (with precipitation of 20 mm or more in 12 hours or less);
- heavy snowstorms(wind speed 15 m/s or more);
dust storms;
frost (when the air temperature drops below 0°C during the growing season on the soil surface);
- severe frost or extreme heat.
These natural phenomena, in addition to tornadoes, hail and squalls, lead to natural disasters, as a rule, in three cases: when they occur in one third of the territory of the region (krai, republic), cover several administrative regions and last at least 6 hours.
Hurricanes and storms
In the narrow sense of the word, a hurricane is defined as a wind of great destructive power and considerable duration, the speed of which is approximately equal to 32 m/s or more (12 points on the Beaufort scale).
A storm is a wind that is slower than a hurricane. Losses and destruction from storms are significantly less than from hurricanes. Sometimes a strong storm is called a storm.
The most important characteristic of a hurricane is its wind speed.
The average duration of a hurricane is 9 - 12 days.
A storm is characterized by a lower wind speed than a hurricane (15-31 m/s). Duration of storms- from several hours to several days, width - from tens to several hundreds of kilometers. Both of them are often accompanied by fairly significant precipitation.
Hurricanes and storm winds in winter conditions often lead to snow storms, when huge masses of snow move at high speed from one place to another. Their duration can be from several hours to several days. Especially dangerous are snow storms that take place simultaneously with snowfall, at low temperatures or with sharp changes in it.
Classification of hurricanes and storms.Hurricanes are usually divided into tropical and extratropical. In addition, tropical hurricanes are often divided into hurricanes that originate over the Atlantic Ocean and over the Pacific. The latter are called typhoons.
There is no generally accepted, established classification of storms. Most often they are divided into two groups: vortex and flow. Vortexes are complex eddy formations caused by cyclonic activity and spreading over large areas. Streams are local phenomena of small distribution.
Vortex storms are subdivided into dust, snow and squall storms. In winter they turn into snow. In Russia, such storms are often called blizzard, snowstorm, snowstorm.
Tornado - this is an ascending vortex, consisting of extremely rapidly rotating air mixed with particles of moisture, sand, dust and other suspensions. It is a rapidly rotating air funnel hanging from a cloud and falling to the ground in the form of a trunk.
Occurs both above the water surface and over land. Most often - during hot weather and high humidity, when air instability in the lower layers of the atmosphere appears especially sharply.
A funnel is the main component of a tornado. It is a spiral vortex. Its inner cavity in diameter is from tens to hundreds of meters.
It is extremely difficult to predict the place and time of the appearance of a tornado.Tornado classification.
Most often they are subdivided according to their structure: dense (sharply limited) and vague (indistinctly limited). In addition, tornadoes are divided into 4 groups: dust whirlwinds, small short-acting, small long-acting, hurricane whirlwinds.
Small short-acting tornadoes have a path length of no more than a kilometer, but have significant destructive power. They are relatively rare. The length of the path of small long-acting tornadoes is estimated at several kilometers. Hurricane whirlwinds are larger tornadoes and travel several tens of kilometers during their movement.
Dust (sand) stormsaccompanied by the transfer of large quantities of soil and sand particles. They arise in desert, semi-desert and plowed steppes and are capable of carrying millions of tons of dust over hundreds and even thousands of kilometers, covering an area of several hundred thousand square kilometers.
Dustless storms. They are characterized by the absence of dust entrainment into the air and a relatively smaller scale of destruction and damage. However, with further movement, they can turn into dusty or snow storm depending on the composition and condition of the earth's surface and the presence of snow cover.
snow storms characterized by significant wind speeds, which contributes to the movement of huge masses of snow through the air in winter. Their duration varies from several hours to several days. They have a relatively narrow band of action (up to several tens of kilometers).
1.5. Natural disasters of a hydrological nature and marine hazardous hydrometeorological phenomena
These natural phenomena are divided into disasters caused by:
High water level - floods, in which the lowered parts of cities and other settlements, crops are flooded, damage to industrial and transport facilities;
Low water level, when navigation, water supply of cities and national economic facilities, irrigation systems are disrupted;
Mudflows (during the breakthrough of dammed and moraine lakes that threaten settlements, road and other structures);
Snow avalanches (in case of a threat to settlements, automobile and railways, power lines, industrial and agricultural facilities);
Early freezing and the appearance of ice on navigable water bodies.
To marine hydrological phenomena: tsunamis, strong waves on the seas and oceans, tropical cyclones (typhoons), ice pressure and their intense drift.
floods - this is flooding with water adjacent to a river, lake or reservoir area, which causes material damage, damages the health of the population or leads to death of people. If flooding is not accompanied by damage, it is a flood of rivers, lakes, reservoirs.
Especially dangerous floods are observed on the rivers of rain and glacier feeding or a combination of these two factors.
High water is a significant and rather long rise in the water level in the river, which repeats annually in the same season. Usually floods are caused by spring snowmelt on the plains or rainfall.
A flood is an intense, relatively short-term rise in the water level. It is formed by heavy rains, sometimes by melting snow during winter thaws.
The most important basic characteristics are the maximum level and maximum flow of water during the flood. With the area, layer and duration of flooding of the area are related to the maximum level. One of the main characteristics is the rate of rise of the water level.
For large river basins an important factor is one or another combination of flood waves of individual tributaries.
For flood cases, the factors affecting the values of the main characteristics include: the amount of precipitation, their intensity, duration, coverage area preceding precipitation, basin moisture content, soil water permeability, basin topography, river slopes, presence and depth of permafrost.
Ice jams and ice jams on rivers
Congestion An accumulation of ice in a channel that limits the flow of a river. As a result, water rises and spills.
The jam is usually formed at the end of winter and in the spring when rivers open up during the destruction of the ice cover. It consists of large and small ice floes.
Zazhor - a phenomenon similar to ice jam. However, firstly, the congestion consists of an accumulation loose ice(slush, small ice floes), while the jam is an accumulation of large and, to a lesser extent, small ice floes. Secondly, ice jam occurs at the beginning of winter, while ice jam occurs at the end of winter and in spring.
The main reason for the formation of congestion is the delay in the opening of ice on those rivers where the edge of the ice cover in the spring shifts from top to bottom. At the same time, crushed ice moving from above meets on its way an ice cover that has not yet been broken. The sequence of breaking up the river from top to bottom is a necessary but not sufficient condition for the occurrence of a jam. The main condition is created only when the surface velocity of the water flow during the opening is quite significant.
Zazhors are formed on the rivers during the formation of the ice cover. A necessary condition for the formation is the occurrence of intra-water ice in the channel and its involvement under the edge of the ice cover. In this case, the surface velocity of the current, as well as the air temperature during the freezing period, are of decisive importance.
Surges is the rise in water level caused by the action of wind on the water surface. Such phenomena occur in the sea mouths of large rivers, as well as on large lakes and reservoirs.
The main condition for the occurrence is a strong and prolonged wind, which is typical for deep cyclones.
Tsunami are long waves resulting from underwater earthquakes, as well as volcanic eruptions or landslides on the seabed.
Their source is at the bottom of the ocean,
In 90% of cases, tsunamis are caused by underwater earthquakes.
Often, before a tsunami begins, water recedes far from the coast, exposing the seabed. Then the impending one becomes visible. At the same time, thunderous sounds are heard, created by an air wave, which the water mass carries in front of it.
The possible scale of consequences is classified by severity:
1 point - the tsunami is very weak (the wave is recorded only by instruments);
2 points - weak (it can flood a flat coast. Only specialists notice it);
3 points - average (noted by all. The flat coast is flooded. Light ships may be washed ashore. Port facilities may receive minor damage);
4 points - strong (the coast is flooded. Coastal buildings are damaged. Large sailing and small motor vessels can be washed ashore, and then washed back into the sea. Human casualties are possible);
5 points - very strong (coastal areas are flooded. Breakwaters and breakwaters are badly damaged, Large ships are washed ashore. There are casualties. Material damage is great).
1.6. natural fires
This concept includes forest fires, fires of steppe and grain massifs, peat and underground fires of fossil fuels. We will focus only on forest fires, as the most common phenomenon that brings enormous losses and sometimes leads to human casualties.
Forest fires - this is an uncontrolled burning of vegetation, spontaneously spreading through the forest area.
In hot weather, if there is no rain for 15 to 18 days, the forest becomes so dry that any careless handling of fire causes a fire that quickly spreads through the forest area. A negligible number of fires occur from lightning discharges and spontaneous combustion of peat chips. The possibility of forest fires is determined by the degree of fire danger. For this purpose, a "Scale for assessing forest areas according to the degree of risk of fires in them" was developed (see. Table 3)
Forest fire classification
Depending on the nature of the fire and the composition of the forest, fires are divided into grassroots, riding, soil. Almost all of them at the beginning of their development are grassroots and, if certain conditions are created, they pass into upland or soil.
The most important characteristics are the speed of propagation of ground and crown fires, the depth of burning underground. Therefore, they are divided into weak, medium and strong. According to the speed of the spread of fire, grassroots and horseback are divided into stable and runaway ones. The intensity of burning depends on the state and stock of combustible materials, the slope of the terrain, the time of day, and especially the strength of the wind.
2. Natural emergencies in the Nizhny Novgorod region.
The region has enough great variety climatic, landscape and geological conditions, which causes the occurrence of various natural phenomena. The most dangerous of them are those that can cause significant material damage and lead to death of people.
- dangerous meteorological processes:squally and hurricane-force winds, heavy rain and snow, downpours, large hail, severe snowstorm, severe frost, ice-frost deposits on wires, extreme heat (high fire hazard due to weather conditions);agrometeorological,such as frost, drought;
- dangerous hydrological processes,such as high water (in the spring period, the rivers of the region are characterized by high water levels, possible separation of coastal ice floes, jamming phenomena), rain flood, low water levels (in summer, autumn and winter, water levels are likely to drop to unfavorable and dangerous levels);hydrometeorological(separation of coastal ice floes with people);
- natural fires(forest, peat, steppe and wetland fires);
- dangerous geological phenomena and processes:(landslides, karsts, subsidence of loess rocks, erosion and abrasion processes, slope washouts).
Over the past thirteen years, of all registered natural phenomena that had a negative impact on the life of the population and the operation of economic facilities, the share of meteorological (agrometeorological) hazards was 54%, exogenous-geological - 18%, hydrometeorological - 5%, hydrological - 3%, large forest fires - 20%.
The frequency of occurrence and the territory of distribution of the above natural phenomena in the region are not the same. The actual data of 1998 - 2010 make it possible to classify meteorological phenomena (damaging squally wind increases, the passage of thunderstorm fronts with hail, ice-frost deposits on wires) as the most common and frequently observed - annually, on average, 10 - 12 cases are recorded.
At the end of winter and the spring period of each year, events are held to rescue people from detached coastal ice floes.
Natural fires occur annually and water levels rise during the flood period. Adverse consequences of the passage of forest fires and high water levels are recorded quite rarely, which is due to pre-planned preparations for the flood and the fire hazard period.
spring flood
The passage of high water in the region is observed from the end of March to May. According to the degree of danger, the flood in the region belongs to a moderately dangerous type, when the maximum levels of water rise by 0.8 - 1.5 m exceed the levels of the beginning of flooding, flooding of coastal areas (emergency situations at the municipal level). The floodplain area of the river is 40 - 60%. Settlements are usually subject to partial flooding. The frequency of exceeding the water level above the critical level is every 10 - 20 years. Excesses of critical levels on most of the region's rivers were registered in 1994, 2005. In varying degrees, 38 districts of the region are subject to the action of hydrological processes during the spring flood. The results of the processes are flooding and flooding of residential buildings, livestock and agricultural complexes, destruction of road sections, bridges, dams, dams, damage to power lines, and activation of landslides. According to recent data, the areas most prone to floods were Arzamas, Bolsheboldinsky, Buturlinsky, Vorotynsky, Gaginsky, Kstovsky, Perevozsky, Pavlovsky, Pochinkovsky, Pilninsky, Semenovsky, Sosnovsky, Urensky and Shatkovsky.
Increased ice thickness can cause congestion on rivers during the opening period. The number of ice jams on the rivers of the region reaches an average of 3-4 per year. The flooding (flooding) caused by them is most likely in settlements located along the banks of rivers flowing from south to north, the opening of which occurs in the direction from the source to the mouth.
Forest fires
In total, there are 304 settlements in the region in 2 urban districts and 39 municipal areas, which may be subject to negative impact forest peat fires.
The danger of wildfires is associated with the occurrence of large wildfires. Fires, the area of which reaches 50 hectares, account for 14% of the total number of large forest fires, fires from 50 to 100 hectares occupy 6% of the total, fires from 100 to 500 hectares - 13%; the proportion of large forest fires exceeding 500 hectares is small - 3%. This ratio changed significantly in 2010, when the bulk (42%) of large forest fires reached an area of more than 500 ha.
The number and area of wildfires vary significantly from year to year, because they directly depend on weather conditions and anthropogenic factor (forest attendance, preparation for the fire season, etc.).
It should be noted that in almost the entire territory of Russia in the period up to 2015. should be expected in the summer periods an increase in the number of days from high values air temperature. At the same time, the probabilities of extremely long periods with critical air temperatures will increase significantly. As a result, by 2015 compared to the current values, an increase in the number of days with a fire hazard is predicted.
- DISASTER PROTECTION MEASURES.
For many centuries, humanity has developed a fairly coherent system of measures to protect against natural disasters, the implementation of which in various parts of the world could significantly reduce the number of human casualties and the amount of material damage. But before today Unfortunately, we can only talk about individual examples of successful opposition to the elements. Nevertheless, it is advisable to list once again the main principles of protection against natural disasters and compensation for their consequences. A clear and timely forecast of the time, place and intensity of a natural disaster is necessary. This makes it possible to timely notify the population about the expected impact of the elements. A properly understood warning allows people to prepare for a dangerous event by either temporary evacuation, or building protective engineering structures, or strengthening their own homes, livestock buildings, etc. The experience of the past must be taken into account, and its hard lessons must be brought to the attention of the population with the explanation that such a disaster may happen again. In some countries, the state is buying up land in areas of potential natural disasters and organizing subsidized transfers from hazardous areas. Insurance is essential to reduce losses from natural disasters.
An important role in the prevention of damage from natural disasters belongs to the engineering-geographical zoning of zones of possible natural disasters, as well as the development building codes and rules that strictly regulate the type and nature of construction.
AT various countries sufficiently flexible legislation on economic activity in areas of natural disasters has been developed. If a natural disaster occurred in a populated area and the population was not evacuated in advance, emergency rescue operations are carried out, followed by repair and restoration.
Conclusion
So, I studied natural emergencies.
I have come to the conclusion that there is big variety natural disasters. These are dangerous geophysical phenomena; dangerous geological phenomena; dangerous meteorological phenomena; marine dangerous hydrometeorological phenomena; dangerous hydrological phenomena; natural fires. There are 6 types and 31 species in total.
Natural emergencies can lead to human casualties, damage to human health or the environment, significant losses and disruption of people's living conditions.
From the point of view of the possibility of carrying out preventive measures, hazardous natural processes, as a source of emergency situations, can be predicted with a very short lead time.
In recent years, the number of earthquakes, floods, landslides and other natural disasters has been constantly increasing. This cannot go unnoticed.
List of used literature
1. V.Yu. Mikryukov "Ensuring life safety" Moscow - 2000.
2. Hwang T.A., Hwang P.A. Life safety. - Rostov n / a: "Phoenix", 2003. - 416 p.
3. Reference data on emergencies of technogenic, natural and ecological origin: At 3 o'clock - M.: GO USSR, 1990.
4. Emergencies: Brief description and classification: Proc. allowance / Ed. allowances A.P. Zaitsev. - 2nd ed., corrected. and additional - M.: Zhurn. "Military knowledge", 2000.
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