Examples of catastrophic natural phenomena. The worst natural disasters

Catastrophe is a sudden occurrence of a natural phenomenon or a human action, which entailed numerous human casualties or caused damage to the health of a group of people who at the same time needed an emergency medical care or protection, which caused a disproportion between the forces and means or forms and methods of the daily work of health authorities and institutions, on the one hand, and the emerging need of victims for emergency medical care, on the other hand.
In the period from 2000 to 2012, as a result of disasters, over 700 thousand people died, 1.4 million were injured, and about 23 million were left homeless. In total, 1.5 billion people have been affected in one way or another by disasters. The total economic damage amounted to $ 1.3 trillion (for comparison: Russia's GDP in 2013 - $ 2.097 trillion).
Natural and man-made disasters cause damage that affects all spheres of society. The devastating consequences of disasters are often long-term.
Disasters demonstrate the physical, social, economic and environmental vulnerability and insecurity of the human population.
An important task of our time is to improve the forecasting of disasters and the development of methods for the rapid and effective elimination of their consequences.
Most destructive disasters are of natural origin (earthquakes, extreme weather events). However, the Intergovernmental Panel on Climate Change has demonstrated that a number of measures can be taken to reduce the severity and frequency of extreme weather events caused by anthropogenic climate change. They are about introducing sustainable development practices that aim to protect the environment while at the same time improving the health and well-being of people.
In order to avoid man-made disasters, regular inspections of the equipment of enterprises and infrastructure facilities that pose a potential danger (railways, factories, stations) should be carried out for wear and other necessary measures to prevent man-made disasters and eliminate their consequences.
This paper will consider the main types of natural and man-made disasters, their causes, consequences, as well as examples of the world's largest natural and man-made disasters.

2. Classification

There are several criteria for the classification of disasters. These include: damage caused, time of occurrence, coverage area, number of victims, and others. One of the most common criteria is the nature of the origin. On this basis, they usually distinguish:

• Anthropogenic disasters - occur due to human activities (shipwreck, accidents at nuclear power plants);
• Natural disasters - occur under the influence of the forces of nature (tsunamis, earthquakes, floods).

It should be noted that anthropogenic disasters in a broad sense can be of a natural nature (landslides in settlements caused by malfunctioning water supply systems; floods due to dam breakthroughs). Here, anthropogenic catastrophes will be considered as opposed to natural ones. In other classifications, man-made disasters are distinguished.

3. Natural disasters

Classification of natural disasters

Natural disasters are divided into two types according to their origin:

1. endogenous - associated with the internal energy and forces of the Earth (volcanic eruptions, earthquakes, tsunamis);
2. exogenous - caused by solar energy and activity, atmospheric, hydrodynamic and gravitational processes (hurricanes, cyclones, floods, storms).

Causes of natural disasters

One of the reasons for the occurrence of natural disasters is a natural disaster, a natural phenomenon that leads to the destruction of material values, death of people and other consequences.
The main types of natural disasters:

1. Geological

• Earthquake
  Earthquake - tremors and vibrations of the earth's surface resulting from sudden displacements and ruptures in the earth's crust and upper mantle and transmitted over long distances.
• Eruption
  A volcanic eruption is a volcanic activity in which volcanic lava and hot gases burst to the surface. In addition to the direct eruption of the volcano, great damage is caused by the release of volcanic ash and pyroclastic flows (a mixture of volcanic gases, stones, ash).
• Avalanche
  An avalanche is a mass of snow or ice that falls or slides off steep mountain slopes. Particularly destructive avalanches can completely destroy populated areas.
• Collapse
  Collapse - separation of rock masses from the slope and fast travel way down. They arise on the banks of rivers, seas, in the mountains under the influence of precipitation, seismic shocks, human activity
• Landslide
  Landslide - the separation of earth masses from the slope and their movement along the slope under the influence of gravity.
• Mud
  Mudflow is a powerful mud, mud-stone or water-stone flow that forms in the beds of mountain rivers due to a sharp flood caused by heavy rainfall, snow melting and other reasons.

2. Meteorological

• Hail
  Hail - a type of precipitation in the form of dense ice particles (hailstones) irregular shape different sizes.
• Drought
  Drought is prolonged dry weather, often at elevated air temperatures, with no or very little atmospheric precipitation, leading to depletion of moisture reserves in the soil and a sharp decrease in the relative humidity of the air.
• Blizzard
  Blizzard - the transfer of snow by the wind over the surface of the earth.
• Tornado
  Tornado is an extremely strong atmospheric vortex with air circulation closed around a more or less vertical axis.
• Cyclone
  A cyclone is an atmospheric vortex with reduced pressure in the middle and air circulation in a spiral.

3. Hydrological

• Flood
  Flood - flooding of an area with water.
• Tsunami
  Tsunamis are very long sea waves that occur during strong underwater and coastal earthquakes, as well as during volcanic eruptions or large landslides rocks from the coastal cliff.
• Limnological catastrophe
  A limnological disaster is a rare natural phenomenon in which carbon dioxide dissolved in deep lakes is released to the surface, causing asphyxiation of wild and domestic animals and people.

4. Fires

• Forest fires
  Forest fires - spontaneous or human-induced ignition in forest ecosystems
• Peat fires
  Peat fires - burning of a layer of peat and tree roots.

The impact of space objects on the Earth is distinguished into a separate group of causes of natural disasters: collisions with asteroids, falling meteorites. They pose a great threat to the planet, since even small in size heavenly body can cause devastating damage on impact with the Earth.

Consequences of natural disasters

Killed and wounded

Between 1965 and 1999, 4 million people fell victim to the main types of natural disasters.
Geographically, the number of deaths from natural disasters is divided as follows: more than half (53%) are in Africa, 37% in Asia. The most destructive in Africa were droughts, and in Asia - cyclones, storms, tsunamis.
In terms of the number of people affected by natural disasters, Asia dominates all continents (89%). Africa is in second place (6.7%), followed by America, Europe and Oceania with a total of 5%.
The number of people affected by various natural disasters in Asia:

• 55% from floods
• 34% from droughts
• 9% from tsunamis and storms

Economic damage

The vulnerability of countries to natural disasters is related to their social and economic development... Cities with a high population density and developed infrastructure suffer the greatest economic, social and material damage.
In absolute terms, the economic damage is greater for developed countries due to extensive infrastructure and high concentration of capital. However, the ratio of direct damage to GDP shows that low-income countries suffer more damage.
The economic damage from natural disasters is growing rapidly every year. In the 1960s, it amounted to about $ 1 billion, in the 1970s - 4.7, in the 1980s - 16.6, in the 1990s - 76. There have been cases when the damage to the economy from the catastrophe exceeded the GDP.
The most economically devastating natural disasters are typhoons, storms, floods and earthquakes. This can be seen by examining the diagram of economic damage to Europe from natural disasters (Figure 1)

Figure 1. Economic damage European countries from natural disasters (1989-2008)

Impact of natural disasters on the environment

Under the influence of natural disasters, large-scale changes in the geographical setting or the type of landscape occur, which lead to certain successive changes in the state of biogeocenoses of the area (successions).

4. Anthropogenic disasters

Classification

Usually, man-made disasters are divided into two main groups:

1. industrial (radiation, chemical emissions)
2. transport (plane crashes, railway accidents)

This is not an exhaustive classification. Fires, social catastrophes (wars, terrorist acts) are sometimes distinguished into separate groups.
Another criterion for classification is origin. Man-made disasters can be caused by negligence and ill-considered actions on the part of personnel, external reasons(in case of shipwrecks), equipment malfunction and many other reasons.
At the scene: accidents at nuclear power plants, chemical industries, bacteriological laboratories, emergencies on the water, railways, air crashes and others.

Causes of occurrence

The main causes of anthropogenic disasters are:

• Equipment malfunction, failure of engineering systems, violation of the operating mode of equipment
• Erroneous actions of personnel, non-observance of safety measures
  External influences

The most frequent man-made disasters:

• explosions and fires in enterprises storing, processing or producing explosives
• in coal mines, underground
• traffic accidents

The main cause of fires is violation of safety rules, technical defects leading to a fire, human negligence, as well as malicious intent.
Explosions occur due to human error, the presence of a high concentration of flammable gases and dust in the air, violation of the rules for storage, transportation and processing of hazardous substances.
Most experts believe that major aircraft crashes are usually caused by engine and other aircraft systems malfunction, pilot error, weather conditions, collisions with objects in the air.
Accidents on railways occur due to defects in the railway track, rolling stock, overload railway line, errors of the track operator and the driver.
There are hundreds of chemical enterprises and nuclear power plants in the world, and the accumulated radioactive and chemical waste is enough to destroy all life on the planet several times.
Chemical accidents are a disruption to the production process, accompanied by damage or destruction of pipelines, tanks, storage facilities, vehicles and leading to the release of chemical pollutants into the biosphere.
Radioactive disasters occur as a result of the loss of control over radioactive material.

Consequences of anthropogenic disasters

In terms of material and energy characteristics, the consequences of anthropogenic disasters can be divided into:

• mechanical
• physical (thermal, electromagnetic, radiation, acoustic)
• chemical
• biological

The consequences of anthropogenic disasters are divided into short-term (destroyed infrastructure) and long-term (radioactive contamination of the environment) according to the period of influence and the time spent on their elimination.
When assessing the scale of anthropogenic catastrophes, various indicators can be taken as a basis: the number of deaths; the total number of victims; the nature of the damage to the environment; financial losses and others.
Like natural disasters, anthropogenic ones cause severe economic damage, although they are inferior to the first in terms of the number of victims.
A distinctive feature of man-made disasters is the serious environmental damage they cause.
Accidents in the fuel and energy complex, aircraft and shipwrecks, accompanied by the release of substances hazardous to ecosystems into the environment, entail the death of organisms, mutations in biological species, and destruction of habitats.
The release of radioactive substances during disasters caused by accidents at nuclear power plants has long-term consequences: death of people from cancer, radiation sickness, hereditary diseases in subsequent generations, radioactive contamination of the environment.
In general, industrial accidents and disasters are a very significant negative factor for the state of the environment. natural environment and public health. The disruption of natural ecosystems and the death of many components of the biota occurring as a result of disasters can be irreversible.

5. Prediction of disasters

To predict a catastrophe means to determine its place, time and strength. A feature of modern natural disasters is that when they occur, there is a combination or simultaneous action of several initiating factors. Seismologists monitor changes in various characteristics of the Earth in order to establish the relationship between them and the occurrence of natural disasters.
However, there are a number of obstacles in determining the causes and the possibility of predicting hazardous natural phenomena and emergencies, which are associated with the peculiarities of the functioning of the existing monitoring and forecasting system.
The difference between man-made disasters and natural disasters is that they are sudden and impossible to predict. But there are prerequisites for anthropogenic catastrophes and ways to predict them.
The prerequisites for anthropogenic catastrophes are physical phenomena that provide objective evidence of the occurrence of a potential anthropogenic catastrophe. Timely detection of prerequisites allows you to take measures to eliminate the disaster or, if it is inevitable, to minimize damage.
Such prerequisites include a defect or failure of equipment for technical reasons or as a result of meteorological, seismic activity; geophysical factors associated with the concentration of hazardous substances at enterprises and others.
Experience in the creation and operation of complex engineering systems has allowed mankind to develop and implement methods for monitoring their safety and performance.
Predicting catastrophes is a complex and important task of our time. The security and development of mankind depends on this.

6. Examples of major disasters

Hurricane Katrina

Flooded New Orleans 23-30 August 2005, USA.
Hurricane Katrina is the most destructive hurricane in US history.
The hurricane hit the coastline along the northern Gulf of Mexico, which is highly vulnerable to storm surge. Zone natural disaster became the states of Louisiana, Mississippi, Alabama and Florida. The total number of victims of the hurricane is close to 2000. Thousands of people were left without homes and jobs, infrastructure facilities in dozens of cities were partially or completely destroyed. The hurricane caused coastal erosion, oil spills. About $ 100 billion has been spent on rebuilding the affected regions.

The Chernobyl accident

Destroyed fourth block Chernobyl nuclear power plant April 26, 1986, USSR.
The accident at the Chernobyl nuclear power plant - the explosive destruction of the fourth power unit of the Chernobyl nuclear power plant with a release into the environment a large number radioactive substances. The largest accident of its kind in the history of nuclear power
the number of victims and economic damage.
On April 26, 1986, an explosion occurred at the 4th power unit of the Chernobyl nuclear power plant, completely destroying the reactor. The main cause of the accident is considered to be personnel error. The consequences of the accident are long-term. The number of victims can only be estimated approximately. It is estimated at tens of thousands (the victims include people suffering or died from radiation sickness, cancer, children with developmental disabilities, those born after an accident, and others). The accident resulted in a tragic ecological disaster. The cloud formed from the burning reactor carried various radioactive materials across Europe and the USSR. Vast territories were exposed to radiation contamination.

Indian Ocean earthquake (2004)

December 26, 2004, Asia.
Underwater earthquake in Indian Ocean caused a tsunami, considered the deadliest natural disaster in history. 18 countries were in the disaster zone, 300 thousand people were affected - local residents and tourists. In Sri Lanka, tsunamis caused the largest railroad disaster in history.

Bhopal disaster

December 3, 1984, India.
The Bhopal disaster is the largest man-made disaster in terms of the number of victims, caused by an accident at a chemical plant for the production of pesticides in the Indian city of Bhopal. As a result of the release of methyl isocyanate vapors, 18 thousand people died. The number of victims varies from 150 to 600 thousand. The official reason has not been established. A safety breach is believed to have caused the crash.

Wreck of "Donja Paz"

December 20, 1987, Philippines
The collision of the Philippine ferry "Dona Paz" with the tanker "Vector" is considered the largest maritime disaster in peacetime.
The collision resulted in a spill and ignition of oil products from the tanker. Both ships sank. About 1,500 people died. It was revealed that the ferry was overloaded, and the tanker was without a license.

Flood in China (1931)

1931, China.
In 1931, South-Central China suffered devastating floods that claimed the lives of 145,000 to 4 million people. The largest rivers of the country emerged from the banks: Yangtze, Huaihe, Yellowhe. This natural disaster is considered the largest natural disaster in history.

Winter of Terror

1950-1951, Europe.
The Winter of Terror is the 1950-1951 season, during which 649 avalanches occurred in the Alps. Avalanches destroyed several settlements in Austria, Switzerland, Yugoslavia, Italy. About 300 people died.

Fires in Russia (2010)

Smoke over European Russia 2010, Russia
Due to the lack of precipitation and abnormal heat from July to September, the European part of Russia was engulfed in forest fires. The disaster killed 55,800 people.
Dozens of cities were heavily smoke-filled.

Limnological disaster at Lake Nyos

Lake Nyos after the limnological disaster on August 21, 1986, Cameroon.
A limnological disaster occurred on Lake Nyos, which resulted in the release of huge amounts of gaseous carbon dioxide. Gas rushed in two streams
along the mountain slope, destroying all living things at a distance of up to 27 km from the lake. The disaster claimed the lives of 1,700 people.

Explosion of the oil platform Deepwater Horizon

Putting out the fire on oil platform Deepwater Horizon April 20, 2010, USA.
Accident in the Gulf of Mexico (80 kilometers off the coast of Louisiana) at the oil Deepwater platform Horizon. One of the largest man-made disasters. The oil spill as a result of the accident was the largest in the history of the United States.
The accident killed 11 people and caused a major environmental disaster.

7. Conclusion

A catastrophe is an unexpected, powerful and uncontrollable phenomenon, natural or anthropogenic in nature, entailing human casualties, economic, environmental and social damage.
From ancient times to modern times, mankind has been confronted with catastrophes and trying to counteract and control them. With the development of science and technology, it was possible to significantly improve methods for predicting disasters and eliminating the consequences of disasters, but at the same time, such problems as global warming, environmental disasters, and mutated forms of life appeared.
Disasters include not only natural disasters (hurricanes, tsunamis, earthquakes), but also "man-made" or man-made disasters (industrial accidents, wars, terrorist acts), which also cause significant environmental damage.
Governments and public organizations unite efforts to develop an international strategy to reduce the impact of disasters. This is a difficult task that requires decisive economic and political action.
The subject of natural and man-made disasters is very extensive, and the world is becoming more and more interested in analysis, review and search for new solutions. The study of disasters is extremely important for the safety and prosperity of humankind.

8. References

1. Akimova T.A., Kuzmin A.P., Khaskin V.V. Ecology. Nature - Man - Technology: Textbook for universities. - M .: UNITI-DANA, 2001 .-- 343 p.
2. Baida S.E. Natural, technogenic and biological and social disasters: patterns of occurrence, monitoring and forecasting; Russian Emergency Situations Ministry. Moscow: FGBU VNII GOChS (FC), 2013.194 p.
3. Great Soviet Encyclopedia: In 30 volumes - M .: "Soviet Encyclopedia", 1969-1978.
4. Geography. Modern Illustrated Encyclopedia / Editor-in-Chief A.P. Gorkin. - M .: Rosmen-Press, 2006 .-- 624 p.
5. Pushkar V.S., Cherepanova M.V. ECOLOGY: NATURAL DISASTERS AND THEIR ENVIRONMENTAL CONSEQUENCES / Resp. ed. I.S. Maiorov Study Guide. - Vladivostok: Publishing house of VSUES, 2003. - 84p.
6. Castleden, R. (2007). Natural disasters that changed the world... New Jersey: Chartwell Books.
7. McDonald, R. (2003). Introduction to natural and man-made disasters and their effects on buildings. Oxford, UK: Architectural Press.
8. McGuire, B., Mason, I. and Kilburn, C. (2002). Natural hazards and environmental change. London: Arnold.
9. Menshikov, V., Perminov, A. and Urlichich, I. (2012). Global aerospace monitoring and disaster management. Vienna: SpringerWienNew York.
10. Sano, Y., Kusakabe, M., Hirabayashi, J., Nojiri, Y., Shinohara, H., Njine, T. and Tanyileke, G. (1990). Helium and carbon fluxes in Lake Nyos, Cameroon: constraint on next gas burst. Earth and Planetary Science Letters, 99 (4), pp. 303-314.

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Natural disasters were still described in the distant past, for example, the "global flood" described in the Bible. Floods are common and can become truly global. For example, the flood in 1931 on the Yangtze River in China flooded an area of ​​300 thousand km², and in some areas the water remained for four months.

The death of the cities of Sodom and Gomorrah described in the Bible, according to scientists, resembles a natural phenomenon - an earthquake. Researchers of Atlantis are inclined to believe that the island was also flooded as a result of an earthquake. During the eruption of Mount Vesuvius, the cities of Herculaneum and Pompeii were buried under a layer of ash. The resulting tsunami may be the result of earthquakes and volcanic eruptions. The eruption of the Krakatoa volcano in 1833 was accompanied by an earthquake. As a result, a tidal wave was formed, which reached the shores of the islands of Java and Sumatra. The death toll was about 300 thousand people.
Natural disasters annually take about 50 thousand lives. Since 1970, statistics have been updated with new data. During the earthquake in America in 1988, according to various estimates, from 25 to 50 thousand people died. Nine out of ten natural disasters are of four types. Floods account for 40%, tropical cyclones 20%, earthquakes and droughts 15%. Tropical cyclones take the lead in terms of the number of victims. Floods cause great material damage. According to R. Cates, the annual damage caused by natural disasters to the world economy is about US $ 30 billion.

Natural disasters are destructive natural processes that cause injury and death.
To study natural disasters, you need to know the nature of each of them. Natural disasters in the form of a tropical cyclone carry the danger of extreme action of all its elements: rain, wind, waves, storm surges. The most destructive are storm surges.
In 1970, in the northern part of the Bay of Bengal, a tropical cyclone caused the sea level to rise by six meters. This led to flooding. As a result of the devastating hurricane and the onset of flooding, about 300 thousand people died, agriculture suffered losses of $ 63 million. 60% of the population was killed, mainly fishermen, 65% of fishing vessels were destroyed. The consequences of the disaster affected the supply of protein food to the entire region.

Tropical cyclones are seasonal. On average, up to 110 incipient hurricanes are traced over the Atlantic from satellites per year. But only 10-11 of them will grow to gigantic proportions. It is necessary to predict the onset of a tropical cyclone in time in order to protect people. Hurricanes are first identified and then tracked from satellites. If a hurricane threat is detected, its path and speed are predicted. The speed and direction of a tropical cyclone can be determined 300 kilometers away by radar. It is very important to identify the area of ​​the coast where the storm surge may begin, as well as the signs of a tornado. Weather services constantly inform the public about the location and characteristics of the cyclone.
Floods are natural disasters that flood coastal areas. The initial stage of flooding begins with overflowing the channel and overflowing the banks. Flooding is the most common natural phenomenon. Floods can occur in permanent and temporary watercourses, but even where rivers and lakes have never been, for example, in areas where there is heavy rainfall.
Densely populated areas of the Earth suffer from floods: China, India, Bangladesh. Flooding in China occurs in the valleys of the Yellow and Yangtze rivers. Despite centuries of experience and hundreds of dams, the population of these areas still falls victim to floods. Severe flooding in the lower Yangtze River in the 20th century caused 60 million people to suffer from famine. During the flood in 1911, 100 thousand people were killed.

Floods are still a big threat today. After heavy rains in 1952, the English resort town of Lynmouth was flooded. The flood destroyed buildings, flooded the streets, and uprooted trees. Large numbers of people vacationing at Linmouth were cut off from solid ground. The next day, the dam burst and 34 people died.

Exist inverse relationship between property damage due to flooding and the number of casualties. Countries with more to lose have every means to prevent or mitigate flooding. Conversely, pre-industrial countries suffer more property damage, but do not have the necessary means to prevent disaster and save people. Flooding can lead to outbreaks of infectious diseases. To combat flooding, dams and dams are being built, reservoirs are being built to collect flood waters, and river beds are deepening.
Earthquakes are natural disasters caused by the sudden release of the energy of the earth's interior in the form of shock waves and vibrations. An earthquake is dangerous due to direct and secondary effects. Direct manifestations due to seismic waves and tectonic movements cause soil displacement. Secondary effects are the cause of subsidence, soil compaction. As a result of secondary effects, cracks are formed on the earth's surface, tsunamis, avalanches, and fires. Powerful earthquake always accompanied by a large number of casualties and material losses. According to statistics, the largest number of victims of this disaster falls on China, the USSR, Japan, Italy. An earthquake kills approximately 14,000 people every year. Zones of destruction from the epicenter of an earthquake can be several tens and hundreds of kilometers. For example, the epicenter of the 1985 earthquake in Mexico was in the Pacific Ocean, near the city of Acapulco. But despite this, it was so powerful that a significant part of the country suffered, especially the capital of Mexico - Mexico City. On the Richter scale, the impact strength reached 7.8 points. Located 300 kilometers from the epicenter, about 250 buildings were destroyed in Mexico City, 20 thousand people were injured. The devastation zone during the earthquake in Guatemala spread 60 kilometers from the epicenter. The ancient capital of Antigua was completely destroyed, 23 thousand people died, 95% of settlements were destroyed.

Natural disasters are very difficult to predict. At the moment, scientists can predict powerful seismic shocks, but cannot indicate the exact time. But there were cases when scientists were able to accurately predict an earthquake. In the Chinese province of Liaoning in 1974, local residents noticed signs of tectonic activity. The area was constantly monitored by geologists, who, after the first aftershocks on February 1, 1975, were able to predict the possibility of devastating earthquake... The authorities took measures to evacuate the population, and four days later an earthquake began, which damaged 90% of the buildings. According to forecasts of experts, the number of victims could reach 3 million people, but thanks to the measures taken, large casualties were avoided.

Up to 2 billion people continue to live in earthquake-prone areas. Resettlement from seismically active zones is a radical measure to preserve the life and health of people.
Volcanic eruptions are natural disasters that have caused the death of 200 thousand people in 500 years. Until now, millions of people live in close proximity to volcanoes. On the island of Martinique in 1902, during a volcanic eruption, the city of Saint-Pierre was destroyed, which was located 8 kilometers from the Mont Pele volcano. The death toll was about 28 thousand people. This is almost the entire population of the city of Saint Pierre. The activity of this volcano was already noted in 1851, but then there were no casualties and destruction. Experts predicted that this eruption would be similar to the previous one 12 days before the start of the eruption, so none of the residents attached great importance to the beginning of the approaching disaster.

In 1985, the Ruiz volcano in Colombia "woke up". This volcanic eruption resulted in a huge number of casualties and property damage. Most affected was the city of Amero, which was located 40 kilometers from Ruiz. The molten lava and gases melted ice and snow at the top of the mountain, causing a mudflow that completely destroyed the city. Killed 15 thousand people, residents of the city of Amero. 20 thousand hectares of agricultural plantations, highways were destroyed, other settlements were destroyed. The total death toll was 25 thousand people, about 200 thousand were injured.
Natural disasters in the form of volcanic activity cause as much harm as in previous centuries. However, scientists were able to establish the size of the zones of influence of volcanoes. A lava flow spreads over a distance of up to 30 kilometers during large eruptions. Acidic and hot gases pose a threat within a radius of several kilometers. Acid rain, which spreads up to 400-500 kilometers, causes burns in people, poisoning of vegetation and soil.

Natural disasters need to be studied in order to develop a system of measures to protect human health and prevent massive loss of life. The engineering and geographic zoning of natural disaster zones is of great importance.

Natural disasters and their impact on change

physical and geographical location

Physical and geographical position is the spatial location of any terrain in relation to physical and geographical data (equator, prime meridian, mountain systems, seas and oceans, etc.).

Physical and geographical position is determined by geographical coordinates (latitude, longitude), absolute height in relation to sea level, proximity (or remoteness) to the sea, rivers, lakes, mountains, etc., position in the composition (location) of natural (climatic, soil-plant, zoogeographic) zones. This is the so-called. elements or factors of physical and geographical location.

The physical and geographical position of any area is purely individual, unique. The place that each territorial entity occupies is not only individual in itself (in the system of geographical coordinates), but also in its spatial environment, that is, in its location in relation to the elements of the physical and geographical position. Consequently, a change in the physical and geographical position of any area leads, as a rule, to a change in the physical and geographical position of neighboring areas.

A rapid change in the physical and geographical position can only be due to natural disasters or the activities of the person himself.

Hazardous natural phenomena include all those that deviate the state of the natural environment from the range that is optimal for human life and for the economy being conducted by him. Catastrophic natural disasters include those that change the face of the earth.

These are catastrophic processes of endogenous and exogenous origin: earthquakes, volcanic eruptions, tsunamis, floods, avalanches and mudflows, landslides, soil subsidence, a sudden onset of the sea, global climate change on Earth, etc.

In this work, we will consider the physical and geographical changes that have ever occurred or are occurring in our time under the influence of natural disasters.

CHARACTERISTIC OF NATURAL CATACLISMS

Earthquakes

The main source of physical and geographical changes are earthquakes.

An earthquake is a shaking of the earth's crust, underground shocks and vibrations of the earth's surface, caused mainly by tectonic processes. They manifest themselves in the form of tremors, often accompanied by an underground rumble, undulating soil vibrations, the formation of cracks, the destruction of buildings, roads and, most sadly, human casualties. Earthquakes play a prominent role in the life of the planet. More than 1 million tremors are recorded annually on Earth, which averages about 120 tremors per hour or two tremors per minute. We can say that the earth is in a state of constant shuddering. Fortunately, few of them are destructive and disastrous. There is an average of one catastrophic earthquake and 100 destructive earthquakes per year.

Earthquakes occur as a result of the pulsation-oscillatory development of the lithosphere - its compression in some regions and expansion in others. At the same time, tectonic ruptures, displacements and uplifts are observed.

Currently on the globe zones of earthquakes of different activity are identified. The zones of strong earthquakes include the territories of the Pacific and Mediterranean belts... In our country, more than 20% of the territory is prone to earthquakes.

Catastrophic earthquakes (9 points or more) cover areas of Kamchatka, Kuril Islands, Pamir, Transbaikalia, Transcaucasia and a number of other mountainous regions.

Strong (from 7 to 9 points) earthquakes occur in an area stretching a wide strip from Kamchatka to the Carpathians, including Sakhalin, the Baikal region, Sayany, Crimea, Moldova, etc.

As a result of catastrophic earthquakes, large disjunctive dislocations appear in the earth's crust. Thus, during the catastrophic earthquake on December 4, 1957, the Bogdo fault, about 270 km long, appeared in the Mongolian Altai, and the total length of the formed faults reached 850 km.

Earthquakes are caused by sudden, rapid displacements of the wings of existing or newly formed tectonic faults; the voltages that arise in this case can be transmitted over long distances. The occurrence of earthquakes on large faults occurs with a prolonged displacement in opposite directions of tectonic blocks or plates in contact along the fault. In this case, the cohesion forces keep the fracture wings from slipping, and the fracture zone undergoes a gradually increasing shear deformation. When it reaches a certain limit, the fracture is “ripped open” and its wings are displaced. Earthquakes on newly formed faults are considered as a result of the regular development of systems of interacting cracks, uniting into a zone of increased concentration of ruptures, in which a main rupture is formed, accompanied by an earthquake. The volume of the environment, where part of the tectonic stresses is removed and a certain proportion of the accumulated potential energy of deformation is released, is called the focus of the earthquake. The amount of energy released in a single earthquake depends mainly on the size of the displaced fault surface. The maximum known length of faults, ripping during an earthquake, is in the range of 500-1000 km (Kamchatskoe - 1952, Chileyskoe - 1960, etc.), the wings of the faults shifted sideways up to 10 m. The spatial orientation of the fault and the direction of displacement its wings are called the focal mechanism of the earthquake.

Earthquakes capable of changing the face of the Earth are catastrophic earthquakes of magnitude X-XII. Geological consequences of earthquakes, leading to physical and geographical changes: cracks appear on the ground, sometimes gaping;

air, water, mud or sand fountains appear, with the formation of accumulations of clay or piles of sand;

some springs and geysers stop or change their action, new ones appear;

groundwater becomes cloudy (agitated);

landslides, mud and mud flows, landslides occur;

liquefaction of the soil and sandy-clayey rocks;

underwater sliding occurs, and turbid (turbid) flows are formed;

coastal cliffs, river banks, embankments collapse;

seismic sea waves (tsunamis) occur;

avalanches fall;

icebergs break away from ice shelves;

zones of rift disturbances with internal ridges and dammed lakes are formed;

the soil becomes uneven with areas of subsidence and swelling;

seiches appear on lakes (standing waves and stirring waves near the coast);

the regime of ebb and flow is violated;

volcanic and hydrothermal activity is intensifying.

Volcanoes, tsunamis and meteorites

Volcanism is a set of processes and phenomena associated with the movement of magma in the upper mantle, the earth's crust and on the surface of the earth. As a result of volcanic eruptions, volcanic mountains, volcanic lava plateaus and plains, crater and dammed lakes, mud flows, volcanic tuffs, slags, breccias, bombs, ash are formed, volcanic dust and gases are released into the atmosphere.

Volcanoes are located in seismically active belts, especially in the Pacific. In Indonesia, Japan, Central America, there are several dozen active volcanoes - in total on land from 450 to 600 active and about 1000 "dormant" volcanoes. About 7% of the world's population is dangerously close to active volcanoes. There are at least several dozen large submarine volcanoes on the mid-ocean ridges.

In Russia, Kamchatka, the Kuril Islands, and Sakhalin are at risk of volcanic eruptions and tsunamis. Extinct volcanoes are found in the Caucasus and Transcaucasia.

The most active volcanoes erupt on average once every few years, all active nowadays - on average once every 10-15 years. In the activity of each volcano there are apparently periods of relative decrease and increase in activity, measured in thousands of years.

Tsunamis often occur during eruptions of island and underwater volcanoes. Tsunami is a Japanese term for an unusually large sea wave. These are waves of great height and destructive force, arising in the zones of earthquakes and volcanic activity of the ocean floor. The propagation speed of such a wave can vary from 50 to 1000 km / h, the height in the area of ​​origin from 0.1 to 5 m, and near the coast - from 10 to 50 m or more. Tsunamis often cause destruction on the coast - in some cases catastrophic: they lead to erosion of the coast, the formation of turbidity flows. Another cause of ocean tsunamis is underwater landslides and avalanches that break into the sea.

In the last 50 years, there have been about 70 seismogenic tsunamis of dangerous sizes, of which 4% are in the Mediterranean Sea, 8% in the Atlantic, and the rest in the Pacific Ocean. The most tsunami-prone shores are Japan, Hawaiian and Aleutian Islands, Kamchatka, Kuriles, Alaska, Canada, Solomon Islands, Philippines, Indonesia, Chile, Peru, New Zealand, Aegean, Adriatic and Ionian seas. On the Hawaiian Islands, tsunamis with an intensity of 3-4 points occur on average once every 4 years, on the Pacific coast of South America - once every 10 years.

Flooding is the significant flooding of an area as a result of a rise in the water level in a river, lake or sea. Floods are caused by heavy rainfall, melting snow, ice, hurricanes and storms that contribute to the destruction of embankments, dams, dams. Floods can be river (floodplain), surge (on the coast of the seas), flat (flooding of vast catchment areas), etc.

Large catastrophic floods are accompanied by a rapid and high rise in the water level, a sharp increase in the speed of streams, and their destructive force. Devastating floods occur almost every year in various regions of the earth. In Russia, they are most common in the south of the Far East.

flood on Far East in 2013

Space catastrophes are of no small importance. The Earth is constantly bombarded by cosmic bodies ranging in size from fractions of a millimeter to several meters. The larger the size of the body, the less often it falls to the planet. Bodies, the diameter of which is more than 10 m, as a rule, invade the Earth's atmosphere, only weakly interacting with the latter. The bulk of the matter reaches the planet. The speed of space bodies is enormous: from about 10 to 70 km / s. Their collision with the planet leads to the strongest earthquakes, explosion of the body. In this case, the mass of the destroyed matter of the planet is hundreds of times greater than the mass of the fallen body. Huge masses of dust rise into the atmosphere, shielding the planet from solar radiation... The earth is cooling. The so-called "asteroid" or "cometary" winter is coming.

According to one hypothesis, one of these bodies that fell in the Caribbean region hundreds of millions of years ago led to significant physical and geographical changes in this area, the formation of new islands and reservoirs, and along the way to the extinction of most of the animals inhabiting the Earth, in particular dinosaurs ...

Some cosmic bodies could fall into the sea in historical times (5-10 thousand years ago). According to one of the versions, the worldwide flood described in the legends of different peoples could have been caused by a tsunami as a result of a cosmic body falling into the sea (ocean). The body could fall into the Mediterranean and the Black Sea. Their coasts have traditionally been inhabited by peoples.

Fortunately for us, collisions of the Earth with large cosmic bodies are very rare.

NATURAL CATACLISMS IN EARTH HISTORY

Natural disasters of antiquity

According to one hypothesis, natural disasters could cause physical and geographical changes in the hypothetical supercontinent of Gondwana, which existed about 200 million years ago in the southern hemisphere of the Earth.

Southern continents have common history development of natural conditions - they were all part of Gondwana. Scientists believe that the internal forces of the Earth (the movement of mantle matter) led to the split and expansion of a single continent. There is a hypothesis about the cosmic reasons for the change in the external appearance of our planet. It is believed that the collision of an extraterrestrial body with our planet could cause a giant land mass to split. One way or another, the Indian and Atlantic oceans gradually formed in the spaces between the individual parts of Gondwana, and the continents took their present position.

When trying to "collect" together the fragments of Gondwana, one can come to the conclusion that some land areas are clearly lacking. This suggests that there could have been other continents that disappeared as a result of any natural disasters. Until now, disputes about the possible existence of Atlantis, Lemuria and other mysterious lands do not stop.

For a long time it was believed that Atlantis was a huge island (or mainland?), Sunk in the Atlantic Ocean. Currently the bottom Atlantic Ocean well surveyed and established that there is no island that sank 10-20 thousand years ago. Does this mean that Atlantis did not exist? Quite possibly not. They began to look for her in the Mediterranean and Aegean seas. Most likely, Atlantis was located in the Aegean Sea and was part of the Santorian archipelago.

Atlantis

The death of Atlantis is first described in the writings of Plato, myths about its death reach us from the ancient Greeks (the Greeks themselves could not describe this, due to the lack of writing). Historical background suggest that the natural disaster that destroyed the island of Atlantis was the explosion of the Santorian volcano in the 15th century. BC NS.

Everything that is known about the structure and geological history The Santorian archipelago is very reminiscent of the legend of Plato. As shown by geological and geophysical studies, as a result of the Santorian explosion, at least 28 km3 of pumice and ash were thrown out. The products of the release covered the surroundings, their layer thickness reached 30-60 m. The ash spread not only within the Aegean Sea, but also in the eastern part of the Mediterranean Sea. The eruption lasted from several months to two years. In the last phase of the eruption, the inner part of the volcano collapsed and sank hundreds of meters under the waters of the Aegean Sea.

Another type of natural cataclysm that changed the face of the Earth in ancient times is an earthquake. As a rule, earthquakes cause huge damage and lead to casualties, but do not change the physical and geographical position of the regions. Such changes are caused by the so-called. super earthquakes. Apparently, one of these super-earthquakes took place in prehistoric times. A crack up to 10,000 km long and up to 1,000 km wide was found at the bottom of the Atlantic Ocean. This crack could have formed as a result of a super-earthquake. With a source depth of about 300 km, its energy reached 1.5 · 1021 J. And this is 100 times more than the energy of the strongest earthquake. This should have led to significant changes in the physical and geographical position of the surrounding territories.

Floods are another equally dangerous element.

One of the global floods could have been the above-mentioned biblical Flood. As a result, the highest mountain of Eurasia, Ararat, was under water, and on it some expeditions are still looking for the remains of Noah's ark.

global flood

Noah's ark

During the entire Phanerozoic (560 Ma) eustatic fluctuations did not stop, and in some periods the water level of the World Ocean rose by 300-350 m relative to its present position. At the same time, significant areas of land (up to 60% of the continental area) were flooded.

Cosmic bodies also changed the face of the Earth in antiquity. The fact that in prehistoric times asteroids fell into the ocean is evidenced by craters at the bottom of the World Ocean:

Mjolnir crater in the Barents Sea. Its diameter was about 40 km. It arose as a result of the fall of an asteroid with a diameter of 1-3 km into the sea with a depth of 300-500 m. It happened 142 million years ago. An asteroid at a distance of 1,000 km caused a tsunami with a height of 100-200 m;

Lokne crater in Sweden. Formed about 450 million years ago by the fall of an asteroid with a diameter of about 600 m into the sea with a depth of 0.5-1 km. The cosmic body caused a wave with a height of 40-50 m at a distance of about 1 thousand km;

crater Eltanin. Located at a depth of 4-5 km. It arose as a result of the fall of an asteroid with a diameter of 0.5-2 km 2.2 million years ago, which led to the formation of a tsunami with a height of about 200 m at a distance of 1 thousand km from the epicenter.

Naturally, the height of the tsunami waves near the coast was significantly higher.

In total, about 20 craters have been discovered in the world's oceans.

Natural disasters of our time

Now there is no doubt that the past century was marked by a rapid increase in the number of natural disasters and the volume of associated material losses and physical and geographical changes in territories. In less than half a century, the number of natural disasters has tripled. The increase in the number of accidents occurs mainly due to atmospheric-hydrospheric hazards, which include floods, hurricanes, tornadoes, storms, etc. The average number of tsunamis remains virtually unchanged - about 30 per year. Apparently, these events are associated with a number of objective reasons: population growth, increased energy production and release, changes in the environment, weather and climate. It has been proven that the air temperature has increased by about 0.5 degrees Celsius over the past few decades. This led to an increase in the internal energy of the atmosphere by about 2.6 · 1021 J, which is tens and hundreds of times higher than the energy of the strongest cyclones, hurricanes, volcanic eruptions, and thousands and hundreds of thousands of times the energy of earthquakes and their consequences - tsunamis. It is possible that an increase in the internal energy of the atmosphere destabilizes the metastable ocean-land-atmosphere (OSA) system, which is responsible for the weather and climate on the planet. If so, then it is quite possible that many natural disasters are related.

The idea that the growth of natural anomalies is generated by a complex anthropogenic impact on the biosphere was put forward in the first half of the twentieth century by the Russian researcher Vladimir Vernadsky. He believed that the physical and geographical conditions on Earth are generally unchanged and are obliged to the functioning of living things. but economic activity a person upsets the balance of the biosphere. As a result of deforestation, plowing of territories, drainage of bogs, urbanization, the surface of the Earth, its reflectivity, is changing, and the natural environment is being polluted. This leads to a change in the trajectories of heat and moisture transfer in the biosphere and, ultimately, to the appearance of undesirable natural anomalies. Such a complex degradation of the natural environment is the cause of natural disasters leading to global geophysical changes.

The historical genesis of earthly civilization is organically interwoven into the global context of the evolution of nature, which has a cyclical character. It has been established that geographic, historical and social phenomena occurring on the planet do not occur sporadically and arbitrarily, they are in organic unity with certain physical phenomena the surrounding world.

From a metaphysical point of view, the nature and content of the evolution of all life on Earth is determined by the regular change in the historical-metric cycles of the sunspot-forming activity. At the same time, the cycle change is accompanied by all kinds of cataclysms - geophysical, biological, social and others.

Thus, the metaphysical dimension of the fundamental qualities of space and time makes it possible to track and identify the most serious threats and dangers for the existence of earthly civilization at different periods in the development of world history. Proceeding from the fact that the safe evolutionary paths of terrestrial civilization are organically linked with the stability of the planet's biosphere as a whole and the mutual conditionality of the existence of all biological species in it, it is important not only to understand the nature of natural and climatic anomalies and cataclysms, but also to see the ways of salvation and survival of mankind ...

According to existing forecasts, already in the foreseeable the future will happen another change in the global historical and metric cycle. As a result, humanity will face dramatic geophysical changes on planet Earth. According to experts, natural and climatic disasters will lead to a change in the geographic configuration of individual countries, changes in the state of the habitat and ethno-nourishing landscapes. Flooding of vast territories, an increase in the area of ​​sea water areas, soil erosion, and an increase in the number of lifeless spaces (deserts, etc.) will become common phenomena. Changes in environmental conditions, in particular the length of daylight hours, the characteristics of precipitation, the state of the ethnically nourishing landscape, etc., will actively affect the features of biochemical metabolism, the formation of the subconscious and mentality of people.

Analysis of the probable physical and geographical causes of severe floods in Europe in last years(in Germany, as well as in Switzerland, Austria and Romania), carried out by a number of scientists, shows that the root cause of destructive cataclysms is, most likely, the liberation from the ice of the Arctic Ocean.

In other words, due to the ongoing sharp warming of the climate, it is quite possible that the floods are just beginning. The amount of open blue water in the straits between the Arctic islands of the Great Canadian Archipelago has increased. Giant openings appeared even between the northernmost of them - the island of Ellesmere and Greenland.

Liberation from perennial, heavy landfast ice, which previously literally filled the aforementioned straits between these islands, can lead to a sharp increase in the so-called Western runoff of cold Arctic water into the Atlantic (with a temperature of minus 1.8 degrees Celsius) from the western side of Greenland. And this, in turn, will sharply reduce the cooling of this water, which is still flowing out in mass from the eastern side of Greenland, the Gulf Stream going towards it. In the future, the Gulf Stream can be cooled by this drain by 8 degrees Celsius. At the same time, American scientists predicted a catastrophe if the water temperature in the Arctic rises by at least one degree Celsius. Well, if it rises a few degrees, then the ice covering the ocean will melt not in 70-80 years, as American scientists predict, but in less than ten.

According to experts, in the foreseeable future, coastal countries, whose territories are directly adjacent to the waters of the Pacific, Atlantic and Arctic oceans, will be in a vulnerable position. The members of the intergovernmental group of experts on climate change believe that due to the active melting of the glaciers of Antarctica and Greenland, the level of the World Ocean could rise by 60 cm, which will lead to the flooding of some island states and coastal cities. First of all, we are talking about the territories of North and Latin America, Western Europe, South-East Asia.

Such assessments are contained not only in open scientific articles, but also closed studies of special government agencies of the United States and Great Britain. In particular, according to the Pentagon, if in the next 20 years there are problems with the temperature regime of the Gulf Stream in the Atlantic, this will inevitably change the physical and geographical position of the continents, a global crisis of the world economy will come, which will lead to new wars and conflicts in the world.

According to the studies, the planet's greatest resistance to natural disasters and anomalies, thanks to its physical and geographical data, will continue to be preserved by the continent of Eurasia, the post-Soviet space and, above all, the modern territory of the Russian Federation.

We are talking here about what is happening, according to scientists, the movement of the energy center of the Sun to a "large physical and geographical zone" from the Carpathians to the Urals. Geographically, it coincides with the lands " historical Russia", To which it is customary to refer the modern territories of Belarus and Ukraine, the European part of Russia. The action of such phenomena of cosmic origin means a point concentration of solar and other energy on the fauna and flora of the "large physical-geographical zone". In a metaphysical context, a situation arises in which the area of ​​settlement of the peoples of this territory will play a major role in world social processes.

not so long ago there was a sea

At the same time, according to existing geological estimates, the physical and geographical position of Russia, unlike many other countries, will suffer to a lesser extent from the catastrophic consequences of natural changes on Earth. It is expected that the general warming of the climate will contribute to the regeneration of the natural and climatic environment, an increase in the diversity of fauna and flora in certain territories of Russia. Global changes will have a beneficial effect on the fertility of the lands of the Urals and Siberia. At the same time, experts suggest that the territory of Russia is unlikely to avoid large and small floods, the growth of steppe zones and semi-deserts.

CONCLUSION

Throughout the history of the Earth, the physical and geographical position of all elements of the land has changed under the influence of natural disasters.

Changes in the factors of physical and geographical location can occur, as a rule, only under the influence of natural disasters.

The largest geophysical disasters associated with numerous casualties and destructions, changes in the physical and geographical data of territories are caused as a result of seismic activity in the lithosphere, which most often manifests itself in the form of earthquakes. Earthquakes provoke other natural disasters: volcanic activity, tsunamis, floods. Real megatsunami arose when cosmic bodies with dimensions from tens of meters to tens of kilometers fell into the ocean or sea. Such events have happened many times in the history of the Earth.

Many experts of our time recognize the obvious tendency towards an increase in the number of natural anomalies and disasters, the number of natural disasters per unit of time continues to grow. Perhaps this is due to the deterioration of the ecological situation on the planet, with an increase in the temperature of the gas in the atmosphere.

According to experts, due to the melting of Arctic glaciers, new severe floods await the northern continents in the very near future.

Proof of the reliability of geological forecasts are all sorts of natural disasters that have occurred recently. Today, natural anomalous phenomena, temporary climatic imbalances, sharp temperature fluctuations are becoming constant companions of our life. They are increasingly destabilizing the situation and making significant adjustments to the daily life of states and peoples of the world.

The situation is complicated by the increasing influence of the anthropogenic factor on the state of the environment.

In general, the upcoming climatic and geophysical changes, which pose a serious threat to the very existence of the peoples of the world, require states and governments today to be ready to act in crisis conditions. The world is gradually beginning to realize that the problems of the vulnerability of the current ecological system of the Earth and the Sun have acquired the rank of global threats and require immediate resolution. According to scientists, humanity is still able to cope with the consequences of natural and climatic changes.

Legends of different peoples of the world tell about a certain ancient disaster that has comprehended our planet. It was accompanied by terrible floods, earthquakes, volcanic eruptions; the lands were depopulated, and part of the land sank to the bottom of the sea ...

Avalanche of environmental, social and man-made disasters fell upon us with the beginning of the XXI century. Daily messages from all over the world announce new cataclysms of nature: eruptions, earthquakes, tsunamis, tornadoes and forest fires. But not harbingers is it global catastrophe of the earth, because it seems that the next event will become even more destructive, claiming even more lives.

Nature of our planet, united in four elements, as if warning a person: stop! Think about it! Otherwise, you will organize yourself a last judgment with your own hands ...

Fire

Volcanic eruptions. Earth engulfed in the belts of fire of volcanoes. There are four belts in total. The largest is the Pacific Ring of Fire, which has 526 volcanoes. Of these, 328 erupted in the historically foreseeable time.

Fires. So disastrous in its consequences cataclysm of nature like a fire (forest, peat, grass and household), causes enormous damage to the economy Of the earth, claiming hundreds of human lives. According to the World Health Organization, hundreds of deaths each year are caused by the health effects of smoke from forest and peat bog fires. Smoke also provokes traffic accidents.

Earth

Earthquakes. Tremors and vibrations of the planet's surface caused by tectonic processes occur annually throughout Earth, their number reaches a million, but most are so insignificant that they go unnoticed. Strong earthquakes happen on the planet about once every two weeks.

Sliding firmament. It just so happened that a man called himself the master nature... But sometimes it seems that she only tolerates such self-designation, at a certain moment making it clear who is the boss in the house. Her anger is sometimes terrible. Landslides, mudflows and avalanches - slipping of the ground, the descent of snow masses or streams of water carrying fragments of rocks and clay - these sweep away everything in their path.

Water

Tsunami. The nightmare of all the inhabitants of the ocean coast - a giant tsunami wave - arises from an underwater earthquake. The shock causes a rift at the bottom of the sea, along which significant sections of the bottom rise or fall, which leads to the growth of a multi-kilometer column of water. A tsunami appears, carrying billions of tons of water. Colossal energy drives it to a distance of up to 10-15 thousand km. The waves follow each other with an interval of about 10 minutes, propagating with the speed of a jet plane. In the deepest parts of the Pacific Ocean, their speed reaches 1000 km / h.

Floods. An enraged stream of water can tear down entire cities without giving anyone a chance of survival. The reason most often becomes a sharp rise in water to a critical level after prolonged downpours.

Droughts. Who among us doesn't like the sun? Its gentle rays cheer up and bring the world back to life after hibernation ... But it so happens that the abundant sun becomes the cause of the death of crops, animals and people, provokes fires. Drought is one of the most dangerous cataclysms of nature.

Air

Typhoon, or hurricane. Atmosphere Of the earth it is never calm, its air masses are in constant motion. Under the influence of solar radiation, relief and daily rotation of the planet, inhomogeneities arise in the air ocean. Areas of low pressure are called cyclones, high pressure areas are called anticyclones. It is in cyclones that strong winds originate. The largest of cyclones reach thousands of kilometers in diameter and are clearly visible from space thanks to the clouds that fill them. Basically, these are vortices, where air moves in a spiral from the edges to the center. Such eddies, constantly existing in the atmosphere, but born in the tropics - the Atlantic and the eastern part of the Pacific Ocean and reaching wind speeds over 30 m / s, are called hurricanes. Most often, hurricanes originate over heated areas of tropical oceans, but they can also occur in high latitudes near the poles. Of the earth... Similar phenomena in the western part of the Pacific Ocean north of the equator are called typhoons (from the Chinese "typhen", which means "big wind"). The fastest vortices that arise in thunderclouds are tornadoes.

Tornado, or tornado. An air funnel that stretches from a thundercloud to the ground is one of the most powerful and destructive phenomena cataclysms of nature... Tornadoes (they are also tornadoes) occur in the warm sector of the cyclone, when warm air currents collide under the influence of a strong side wind. Quite unexpectedly, this natural disaster can start with regular rain. The temperature drops sharply, a whirlwind appears due to rain clouds and rushes with great speed. It rolls with a deafening roar, drawing in everything that comes in its way: people, cars, houses, trees. The power of a tornado is devastating and the consequences are dire.

Climate change. The global climate change gives no respite to meteorologists or mere mortals. Forecasters continue to mark temperature records, while constantly making mistakes in forecasts, even for the coming days. The current warming is a natural way out of the small ice age of the XIV-XIX centuries.

Who is to blame for cataclysms of nature?

To a large extent, the warming observed over the past 50-70 years is caused by human activities, primarily the release of gases that cause Greenhouse effect... Glaciers are melting, the level of the oceans is rising. This leads to natural disasters: hotter summers, colder winters, floods, hurricanes, droughts, extinction of entire species of flora and fauna. But is it getting ready nature take revenge on a person with global catastrophe of the earth?

Over the billions of years of our planet's existence, certain mechanisms have been formed on it by which nature works. Many of these mechanisms are subtle and harmless, while others are large-scale and carry enormous destruction. In this rating, we will tell you about 11 of the most destructive natural disasters on our planet, some of which can destroy thousands of people and an entire city in a few minutes.

11

Mudflow is a mud or mud-stone flow that suddenly forms in the beds of mountain rivers as a result of heavy rains, rapid melting of glaciers or seasonal snow cover. Deforestation in mountainous areas can serve as a decisive factor in the occurrence - the roots of the trees hold the upper part of the soil, which prevents the occurrence of a mudflow. This phenomenon is short-lived and usually lasts from 1 to 3 hours, typical for small streams up to 25-30 kilometers long. On their way, the streams cut deep channels, which are usually dry or contain small streams. The consequences of mudflows can be catastrophic.

Imagine that a mass of earth, silt, stones, snow, sand fell on the city from the side of the mountains, driven by a strong stream of water. This stream will demolish the dacha buildings located at the foot of the city together with people, and orchards... All this stream will burst into the city, turn its streets into raging rivers with steep banks from ruined houses. Houses will fall off the foundations and, together with people, will be carried away in a stormy stream.

10

Landslide - the sliding of masses of rocks down a slope under the influence of gravity, often while maintaining its cohesion and solidity. Landslides occur on the slopes of valleys or river banks, in the mountains, on the shores of the seas, the most grandiose at the bottom of the seas. The displacement of large masses of earth or rock along the slope is caused in most cases by wetting the soil with rainwater so that the mass of the soil becomes heavier and more mobile. Such large landslides damage agricultural land, businesses, and settlements. To combat landslides, bank protection structures and planting of vegetation are used.

Only rapid landslides, the speed of which is several tens of kilometers, can cause real natural disasters with hundreds of human victims, when there is no time for evacuation. Imagine that huge chunks of soil are rapidly advancing from a mountain directly onto a village or city, and under tons of this land structures are destroyed and people who did not have time to leave the place of the landslide die.

9

A sandstorm is an atmospheric phenomenon in the form of the transfer of large amounts of dust, soil particles and grains of sand by the wind several meters from the ground, with a noticeable deterioration in horizontal visibility. At the same time, dust and sand rise into the air and, at the same time, dust settles over a large area. Depending on the color of the soil in a given region, distant objects acquire a grayish, yellowish or reddish tint. It usually occurs when the soil surface is dry and the wind speed is 10 m / s or more.

Most often, these catastrophic phenomena are found in the desert. A sure sign that a sandstorm is starting is sudden silence. Rustles and sounds disappear with the wind. The desert literally freezes. A small cloud appears on the horizon, which rapidly grows and turns into a black and purple cloud. The missing wind rises and very quickly reaches speeds of up to 150-200 km / h. Sandstorms can cover streets with sand and dust within a radius of several kilometers, but the main danger of sandstorms is wind and poor visibility, which causes car accidents, which injure dozens of people, and some even die.

8

An avalanche is a mass of snow falling or sliding off the slopes of the mountains. Snow avalanches pose a significant danger, causing casualties among climbers, ski and snowboarding enthusiasts, and causing significant damage to property. Sometimes avalanches have catastrophic consequences, destroying entire villages and causing the death of dozens of people. Snow avalanches, to one degree or another, are common in all mountainous regions. In winter, they are the main natural danger of the mountains.

The tones of snow are held on top of the mountains by friction. Large avalanches descend at the moment when the force of pressure of the snow mass begins to exceed the force of friction. An avalanche is usually triggered by climatic reasons: a sharp change in weather, rains, heavy snowfalls, as well as mechanical effects on the snow mass, including the impact of rockfalls, earthquakes, etc. on the snow man. The volume of snow in an avalanche can reach several million cubic meters... However, even avalanches with a volume of about 5 m³ can be life-threatening.

7

A volcanic eruption is the process of ejection by a volcano on earth surface hot debris, ash, outpouring of magma, which, pouring out onto the surface, becomes lava. The strongest volcanic eruption can have a time period from several hours to many years. Incandescent clouds of ash and gases, capable of moving at a speed of hundreds of kilometers per hour and rising into the air for hundreds of meters. The volcano emits gases, liquids and solids with high temperatures. This often becomes the cause of the destruction of buildings and the death of people. Lava and other incandescent erupting substances flow down the slopes of the mountain and burn out everything that they meet in their path, bringing innumerable sacrifices and amazing material losses. The only protection against volcanoes is a general evacuation, so the population must be familiar with the evacuation plan and unquestioningly obey the authorities if necessary.

It is worth noting that the danger from a volcanic eruption exists not only for the region around the mountain. Potentially volcanoes threaten the life of all life on Earth, so you shouldn't treat these hot guys with condescension. Almost all manifestations of volcanic activity are dangerous. The danger of boiling lava is understandable. But no less terrible is the ash, which penetrates literally everywhere in the form of a continuous gray-black snowfall that fills the streets, ponds, and entire cities. Geophysicists claim to be capable of eruptions hundreds of times more powerful than ever observed. The largest volcanic eruptions, however, have already occurred on Earth - long before the emergence of civilization.

6

A tornado or tornado is an atmospheric vortex that occurs in a thundercloud and spreads down, often to the very surface of the earth, in the form of a cloud sleeve or trunk tens and hundreds of meters in diameter. Usually, the diameter of a tornado funnel on the ground is 300-400 meters, but if a tornado occurs on the surface of the water, this value can be only 20-30 meters, and when the funnel passes over land it can reach 1-3 kilometers. The largest number of tornadoes is recorded on the North American continent, especially in the central states of the United States. About a thousand tornadoes occur in the United States every year. The most powerful tornado can last up to an hour or more. But most of them exist for no more than ten minutes.

On average, about 60 people die annually from a tornado, mainly from flying or falling debris. However, it happens that huge tornadoes rush at a speed of about 100 kilometers per hour, destroying all buildings on their way. The maximum recorded wind speed in the largest tornado is about 500 kilometers per hour. During such tornadoes, the death toll can go to hundreds, and the number of victims to thousands, not to mention material damage. The reasons for the formation of tornadoes have not yet been fully understood.

5

A hurricane or Tropical Cyclone is a type of low pressure weather system that occurs over a warm sea surface and is accompanied by powerful thunderstorms, heavy rainfall, and storm-force winds. The term "tropical" refers to both the geographic area and the formation of these cyclones in tropical air masses. It is generally accepted, according to the Beaufort scale, that a storm turns into a hurricane when the wind speed is over 117 km / h. The strongest hurricanes are capable of causing not only extreme storms, but also large waves on the sea surface, storm tides and tornadoes. Tropical cyclones can arise and maintain their strength only over the surface of large bodies of water, while over land they quickly lose strength.

Hurricane can cause showers, tornadoes, not big tsunamis and floods. The direct effect of tropical cyclones on land is storm winds that can destroy buildings, bridges and other man-made structures. The strongest permanent winds within the cyclone exceed 70 meters per second. The worst impact from tropical cyclones in terms of casualties has historically been storm tide, which is the rise in sea level caused by a cyclone, which, on average, results in about 90% of casualties. Over the past two centuries, tropical cyclones have killed 1.9 million people worldwide. In addition to the direct effect on residential buildings and economic facilities, tropical cyclones destroy infrastructure, including roads, bridges, and power lines, thereby causing enormous economic damage to the affected areas.

The most destructive and terrible hurricane in US history - Katrina, occurred at the end of August 2005. The most severe damage was caused to New Orleans in Louisiana, where about 80% of the city's area was under water. As a result of the natural disaster, 1,836 residents died and the economic damage amounted to $ 125 billion.

4

Flooding - flooding of an area as a result of a rise in the water level in rivers, lakes, seas due to rains, rapid melting of snow, wind surge on the coast and other reasons, which damages human health and even leads to their death, and also causes material damage ... For example, in mid-January 2009, there was the largest flood in Brazil. Then more than 60 cities were affected. About 13 thousand people left their homes, more than 800 people died. Floods and numerous landslides are caused by heavy rainfall.

Heavy monsoon rains have continued in Southeast Asia since mid-July 2001, causing landslides and flooding in the Mekong River area. As a result, Thailand has experienced its worst flooding in half a century. Streams of water flooded villages, ancient temples, farms and factories. At least 280 people have died in Thailand, and another 200 in neighboring Cambodia. Around 8.2 million people in 60 of Thailand's 77 provinces were affected by the flooding, and economic losses for currently estimated to exceed $ 2 billion.

Drought - a long period stable weather with high air temperatures and low precipitation, as a result of which the moisture reserves of the soil decrease and the oppression and death of cultural occurs. The beginning of a severe drought is usually associated with the establishment of a sedentary high anticyclone. Abundance solar heat and the gradually decreasing air humidity creates increased evaporation, and therefore the reserves of soil moisture are depleted without their replenishment with rains. Gradually, as the soil drought intensifies, ponds, rivers, lakes, springs dry up - a hydrological drought begins.

For example, in Thailand, almost every year, severe floods alternate with severe droughts, when a state of emergency is declared in dozens of provinces, and several million people are somehow affected by the effects of drought. As for the victims of this natural phenomenon, in Africa alone from 1970 to 2010 the death toll from droughts is 1 million.

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Tsunami is long waves generated by a powerful impact on the entire water column in the ocean or other body of water. Most tsunamis are caused by underwater earthquakes, during which there is an abrupt displacement of a section of the seabed. Tsunamis are formed during an earthquake of any strength, but those that arise from strong earthquakes with a magnitude of more than 7 on the Richter scale reach great strength. As a result of an earthquake, several waves propagate. More than 80% of tsunamis occur on the periphery of the Pacific Ocean. First scientific description phenomena gave José de Acosta in 1586 in Lima, Peru after a powerful earthquake, then a strong tsunami 25 meters high burst onto land at a distance of 10 km.

The largest tsunamis in the world occurred in 2004 and 2011. So, on December 26, 2004 at 00:58 there was a powerful earthquake with a magnitude of 9.3 - the second most powerful of all recorded, causing the deadliest of all known tsunamis. The tsunami affected the countries of Asia and African Somalia. The total death toll exceeded 235 thousand people. The second tsunami happened on March 11, 2011 in Japan after the strongest earthquake of magnitude 9.0 with the epicenter, caused a tsunami with a wave height exceeding 40 meters. In addition, the earthquake and the ensuing tsunami caused the accident at the Fukushima I nuclear power plant. As of July 2, 2011, the official death toll from the earthquake and tsunami in Japan is 15,524 people, 7,130 people are missing, 5,393 people injured.

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An earthquake is a tremor and vibrations of the Earth's surface caused by natural causes. Small tremors can also be caused by the rise of lava during volcanic eruptions. About a million earthquakes occur on the entire Earth every year, but most of them are so minor that they go unnoticed. The strongest earthquakes, capable of causing widespread destruction, occur on the planet about once every two weeks. Most of them fall on the bottom of the oceans, and therefore are not accompanied by catastrophic consequences if an earthquake does without a tsunami.

Earthquakes are best known for the devastation they can cause. Destruction of buildings and structures is caused by ground vibrations or giant tidal waves (tsunamis) that occur during seismic displacements on the seabed. A powerful earthquake begins with the rupture and movement of rocks somewhere in the depths of the Earth. This place is called the focus of the earthquake or the hypocenter. Its depth is usually no more than 100 km, but sometimes it reaches 700 km. Sometimes the focus of an earthquake can be at the surface of the Earth. In such cases, if the earthquake is strong, bridges, roads, houses and other structures are torn apart and destroyed.

The largest natural disaster is considered to be an 8.2 magnitude earthquake on July 28, 1976 in the Chinese city of Tangshan, Hebei province. According to official data from the PRC authorities, the death toll was 242,419 people, however, according to some estimates, the death toll reaches 800 thousand people. At 3:42 am local time, the city was destroyed by a strong earthquake. Destruction also took place in Tianjin and in Beijing, located only 140 km to the west. As a result of the earthquake, about 5.3 million homes were destroyed or damaged to the point that it was impossible to live in them. Several aftershocks, the strongest of which had a magnitude of 7.1, resulted in even more casualties. The Tangshan earthquake is the second most fatal in history after the most devastating Shaanxi earthquake in 1556. Then about 830 thousand people died.