Hazardous weather phenomena obzh 6. The most terrible natural phenomena

Natural hazards are extreme climatic or meteorological phenomena that occur naturally at one point or another on the planet. In some regions, such hazards may occur with greater frequency and destructive force than in others. Dangerous natural phenomena grow into natural disasters when the infrastructure created by civilization is destroyed and people die.

1. Earthquakes

Among all natural hazardous phenomena the first place should be given to earthquakes. In places of breaks in the earth's crust, tremors occur, which cause vibrations of the earth's surface with the release of gigantic energy. The resulting seismic waves are transmitted over very long distances, although these waves have the greatest destructive power in the epicenter of the earthquake. Due to strong fluctuations earth's surface massive destruction of buildings.
Since there are quite a lot of earthquakes, and the surface of the earth is quite densely built up, then total people in history who died precisely as a result of earthquakes exceeds the number of all victims of other natural disasters and is estimated at many millions. For example, for last decade Earthquakes have killed over 700,000 people around the world. From the most devastating shocks, entire settlements instantly collapsed. Japan is the most earthquake-affected country, and one of the most catastrophic earthquakes occurred there in 2011. The epicenter of this earthquake was in the ocean near the island of Honshu, according to the Richter scale, the magnitude of the shocks reached 9.1 points. Powerful pushes and subsequent devastating tsunami put out of action the nuclear power plant in Fukushima, destroying three of the four power units. Radiation covered a large area around the station, rendering densely populated areas so valuable in Japanese conditions uninhabitable. A colossal tsunami wave turned into a mess what the earthquake could not destroy. More than 16 thousand people officially died, among which another 2.5 thousand who are considered missing can be safely added. Only in this century destructive earthquakes took place in Indian Ocean, Iran, Chile, Haiti, Italy, Nepal.

2. Tsunami waves

A specific water disaster in the form of tsunami waves often results in numerous casualties and catastrophic destruction. As a result of underwater earthquakes or shifts of tectonic plates, very fast, but hardly noticeable waves arise in the ocean, which grow into huge ones as they approach the coast and enter shallow water. Most often, tsunamis occur in areas with increased seismic activity. A huge mass of water, rapidly moving ashore, blows everything in its path, picks it up and carries it deep into the coast, and then carries it into the ocean with a reverse current. Humans, unable to feel danger like animals, often do not notice the approach of a deadly wave, and when they do, it is too late.
Usually killed by tsunamis more people than from the earthquake that caused it (the last case in Japan). In 1971, the most powerful tsunami ever observed occurred there, the wave of which rose 85 meters at a speed of about 700 km / h. But the most catastrophic was the tsunami observed in the Indian Ocean in 2004, the source of which was an earthquake off the coast of Indonesia, which claimed the lives of about 300 thousand people along a large part of the coast of the Indian Ocean.

A tornado (in America this phenomenon is called a tornado) is a fairly stable atmospheric vortex, most often occurring in thunderclouds. He is a visa...

3. Volcanic eruption

Throughout its history, mankind has remembered many catastrophic volcanic eruptions. When the pressure of magma exceeds the strength of the earth's crust in the weakest places, which are volcanoes, this ends with an explosion and outpourings of lava. But the lava itself, from which you can simply get away, is not so much dangerous as hot pyroclastic gases rushing from the mountain, pierced here and there by lightning, as well as a noticeable effect on the climate of the strongest eruptions.
Volcanologists count about half a thousand dangerous active volcanoes, several dormant supervolcanoes, not counting thousands of extinct ones. So, during the eruption of the Tambora volcano in Indonesia, the surrounding lands were plunged into darkness for two days, 92 thousand inhabitants died, and a cold snap was felt even in Europe and America.
List of some strong volcanic eruptions:

Volcano Laki (Iceland, 1783). As a result of that eruption, a third of the population of the island died - 20 thousand inhabitants. The eruption lasted for 8 months, during which flows of lava and liquid mud erupted from volcanic cracks. The geysers have never been more active. Living on the island at that time was almost impossible. The crops were destroyed, and even the fish disappeared, so the survivors experienced hunger and suffered from unbearable living conditions. This may be the longest eruption in human history.
Volcano Tambora (Indonesia, Sumbawa Island, 1815). When the volcano exploded, the sound of this explosion spread over 2,000 kilometers. Ash covered even the remote islands of the archipelago, 70 thousand people died from the eruption. But even today, Tambora is one of the highest mountains in Indonesia that retains volcanic activity.
Volcano Krakatoa (Indonesia, 1883). 100 years after Tambora, another catastrophic eruption occurred in Indonesia, this time "blowing the roof off" (literally) the Krakatoa volcano. After the catastrophic explosion that destroyed the volcano itself, frightening peals were heard for another two months. A huge amount was released into the atmosphere rocks, ash and hot gases. The eruption was followed by a powerful tsunami with a wave height of up to 40 meters. These two natural disasters together destroyed 34,000 islanders along with the island itself.
Volcano Santa Maria (Guatemala, 1902). After a 500-year hibernation in 1902, this volcano woke up again, starting the 20th century with the most catastrophic eruption, which resulted in the formation of a one and a half kilometer crater. In 1922, Santa Maria again reminded of itself - this time the eruption itself was not too strong, but a cloud of hot gases and ash brought death to 5 thousand people.

4. Tornadoes

Our planet has a variety of dangerous places, which in recent times began to attract a special category of extreme tourists looking for a...

A tornado is a very impressive natural phenomenon, especially in the USA, where it is called a tornado. This is an air stream twisted in a spiral into a funnel. Small tornadoes resemble slender narrow pillars, and giant tornadoes can resemble a mighty carousel directed to the sky. The closer to the funnel, the stronger the wind speed, it begins to drag along ever larger objects, up to cars, wagons and light buildings. In the "tornado alley" of the United States, entire city blocks are often destroyed, people die. The most powerful vortices of category F5 reach a speed of about 500 km/h in the center. The state of Alabama suffers the most every year from tornadoes.

There is a kind of fire tornado, which sometimes occurs in the area of massive fires. There, from the heat of the flame, powerful ascending currents are formed, which begin to twist into a spiral, like an ordinary tornado, only this one is filled with flame. As a result, a powerful draft is formed near the surface of the earth, from which the flame grows even stronger and incinerates everything around. When in 1923 in Tokyo there was catastrophic earthquake, then it caused massive fires that led to the formation of a fiery tornado that rose 60 meters. The column of fire moved towards the square with frightened people and burned 38 thousand people in a few minutes.

5. Sandstorms

This phenomenon occurs in sandy deserts when a strong wind picks up. Sand, dust and soil particles rise to a sufficiently high height, forming a cloud that dramatically reduces visibility. If an unprepared traveler gets into such a storm, he can die from grains of sand falling into the lungs. Herodotus described history as in 525 BC. e. in the Sahara, a 50,000-strong army was buried alive by a sandstorm. In Mongolia, 46 people died as a result of this natural phenomenon in 2008, and two hundred people suffered the same fate the year before.

Throughout the history of mankind, the strongest earthquakes have repeatedly caused enormous damage to people and caused a huge number of casualties among the population ...

6. Avalanches

From the snow-capped mountain peaks periodically descend snow avalanches. Climbers especially often suffer from them. During World War I, up to 80,000 people died from avalanches in the Tyrolean Alps. In 1679, five thousand people died in Norway from snowmelt. In 1886 there was major disaster, as a result of which the "white death" claimed 161 lives. The records of the Bulgarian monasteries also mention the human victims of snow avalanches.

7 Hurricanes

In the Atlantic they are called hurricanes, and in pacific ocean typhoons. These are huge atmospheric vortices, in the center of which the strongest winds and sharply reduced pressure are observed. In 2005, the devastating hurricane Katrina swept over the United States, which especially affected the state of Louisiana and the densely populated New Orleans located at the mouth of the Mississippi. 80% of the city was flooded, killing 1836 people. Notable destructive hurricanes have also become:

Hurricane Ike (2008). The diameter of the eddy was over 900 km, and in its center the wind was blowing at a speed of 135 km/h. In the 14 hours that the cyclone moved across the United States, it managed to cause $30 billion worth of damage.
Hurricane Wilma (2005). This is the largest Atlantic cyclone in the history of meteorological observations. A cyclone that originated in the Atlantic made landfall several times. The amount of damage inflicted by him amounted to $ 20 billion, 62 people died.
Typhoon Nina (1975). This typhoon was able to breach China's Bankiao Dam, causing the dams below to collapse and causing catastrophic flooding. The typhoon killed up to 230,000 Chinese.

8. Tropical cyclones

These are the same hurricanes, but in tropical and subtropical waters, which are huge atmospheric systems low pressure with winds and thunderstorms, often exceeding a thousand kilometers in diameter. Near the surface of the earth, winds in the center of the cyclone can reach speeds of over 200 km/h. Low pressure and wind cause coastal storm surge - when ashore from high speed colossal masses of water are thrown out, washing away everything in its path.

It is difficult to scare a Russian person with anything, especially bad roads. Even safe tracks take thousands of lives a year, let alone those a...

9. Landslide

Prolonged rains can cause landslides. The soil swells, loses its stability and slides down, taking with it everything that is on the surface of the earth. Most often, landslides occur in the mountains. In 1920, the most devastating landslide occurred in China, under which 180 thousand people were buried. Other examples:

Bududa (Uganda, 2010). Due to mudflows, 400 people died, and 200 thousand had to be evacuated.
Sichuan (China, 2008). Avalanches, landslides and mudflows caused by an 8-magnitude earthquake claimed 20,000 lives.
Leyte (Philippines, 2006). The downpour caused a mudflow and a landslide that killed 1,100 people.
Vargas (Venezuela, 1999). Mudflows and landslides after heavy rains (almost 1000 mm of precipitation fell in 3 days) on the northern coast led to the death of almost 30 thousand people.

10. Fireballs

We are accustomed to the usual linear lightning accompanied by thunder, but much more rare and mysterious are fireballs. The nature of this phenomenon is electrical, but scientists cannot yet give a more accurate description of ball lightning. It is known that it can have different sizes and shapes, most often these are yellowish or reddish luminous spheres. For unknown reasons, ball lightning often ignores the laws of mechanics. Most often they occur before a thunderstorm, although they can appear in absolutely clear weather, as well as indoors or in the cockpit. The luminous ball hangs in the air with a slight hiss, then it can start moving in an arbitrary direction. Over time, it seems to shrink until it disappears altogether or explodes with a roar.

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5th grade

Weather conditions and human security

Weather - what should be understood by it?

You already know that the Earth is surrounded by an air shell - atmosphere. The air shell of the Earth is very mobile, unstable and changeable. Changes in the air shell of the Earth and determine the weather.

Weather It is the state of the atmosphere at a certain place and at a certain time.

Main weather indicators:

First indicator- this is temperature ambient air, which fluctuates depending on the season, time of day and temperature air mass over a certain area.
The second important indicator- this is Atmosphere pressure , which affects the movement of air - wind.

Third indicator it's in ether The wind is characterized by the direction (from where it blows) and the speed of air movement.

Depending on the speed of air movement, there are:

fresh breeze - wind speed from 5 to 10 m/s (18-36 km/h),

Storm (storm) - wind whose speed over 20 m/s (72 km/h)

A short-term increase in wind up to 30 m / s is called - squall

Hurricane - wind with a speed greater than

30 m/s (more than 100 km/h)

Thunderstorm - stormy weather with rain, thunder and lightning .

Thunderstorms are associated with the development of cumulonimbus clouds, with the accumulation of a large number electricity. Multiple electrical discharges occurring in clouds or between clouds and the ground, are called lightning.
A thunderstorm is necessarily accompanied by peals of thunder and gusts of wind.

the main sign of an approaching thunderstorm .

is an accumulation of powerful cumulonimbus clouds that move rapidly and soon occupy the entire sky.

ice - this is the layer dense ice, which is formed on the earth's surface (sidewalks, carriageway) and on objects (trees, wires, houses, etc.) when drops of supercooled rain and drizzle freeze, usually at an air temperature of 0 to -3 ° C.

Ice thickness during icy conditions can reach several centimeters.

black ice - This is a thin layer of ice that formed on the earth's surface after a thaw or rain as a result of a cold snap, as well as after freezing of wet snow.

snow drift - This is a natural phenomenon associated with abundant snowfall at a speed winds over 15 m/s (54 km/h) and duration of snowfall more than 12 hours .

Blizzard - is the transport of snow by wind in the surface layer of air. Often a blizzard is accompanied by snowfall.

Blizzard - strong wind with snowfall.

Study §3.1
Learn the rules of conduct in the event of natural hazards.
burn folk omens(at least 5 signs) indicating a change in the weather.

1 picture - http://images.clipartpanda.com/weather-clip-art-inclement_weather_Vector_Clipart.png
2 picture - http://3.bp.blogspot.com/-PQ3V-ttpS1s/UopKK13sZWI/AAAAAAAAPdo/HzK1xwbp0KY/s1600/g%C3%BCne%C5%9F+resimleri+%2827%29.png
3 picture - http://yt3.ggpht.com/-Yl76pioRj5A/AAAAAAAAAAI/AAAAAAAAAAA/mH4FKPebItE/s900-c-k-no/photo.jpg
4 picture - Forshtat M.L. Learn to be a walker. Tutorial according to traffic rules for 6th grade. Rice. D.G. Maystrenko/ Cover design by A.S. Andreeva. - St. Petersburg: Publishing House "MiM", 1998.
5 picture - Forshtat M.L. Learn to be a walker. Textbook on traffic rules for grade 6. Rice. D.G. Maystrenko/ Cover design by A.S. Andreeva. - St. Petersburg: Publishing House "MiM", 1998.
6 picture - Fundamentals of life safety. Grade 5: textbook. for general education organizations with app. to an electron. media / A.T. Smirnov, B.O. Khrennikov; ed. A.T. Smirnova; Ros. acad. Sciences, Ros. acad. education, publishing house "Enlightenment". - 3rd ed. – M.: Enlightenment, 2014.
7 picture - Fundamentals of life safety. Grade 5: textbook. for general education organizations with app. to an electron. media / A.T. Smirnov, B.O. Khrennikov; ed. A.T. Smirnova; Ros. acad. Sciences, Ros. acad. education, publishing house "Enlightenment". - 3rd ed. – M.: Enlightenment, 2014.
8 picture - http://picnations.tk/wp-content/uploads/2015/09/Raindrops-on-Leaf-Wallpaper.jpg
9 picture - http://www.province.ru/tyumen/media/k2/items/cache/5003d452a8da016f3ed02a6385cf54e8_XL.jpg
10 picture - http://st.depositphotos.com/1027309/2999/v/950/depositphotos_29992109-Thermometer-snow-sun.jpg
11 picture - http://st2.depositphotos.com/1000489/5709/v/950/depositphotos_57094631-Owl-reading-a-book.jpg

phenomena

Dangerous weather

Weather is the main factor

The weather is the main factor that affects

human safety in natural conditions.

Certain weather events make it difficult

human being in the natural environment.

Going on a hike, you need to find out how the

weather in places of planned rest at different times of the year.

We know that...

From the experience of the organization active rest it has been established in nature that for any locality and each species hiking trip(hiking, mountain, water, ski) it is possible to distinguish the most favorable and unfavorable seasons according to weather conditions.

For mountain and ski trips

Yes, for amateurs mountain hikes The second half of summer (July - August) is considered the most favorable season in almost all regions of the country.

For ski touring middle lane March is preferable northern regions- March, April.

In bad weather

Experienced tourists advise with short-term intense rainfall ( heavy rain) stop at the first convenient place and wait out the bad weather in shelter, under an awning or a cape.

Transitions in the snow and in the rain

You can continue to move in rain and snow on a technically simple section, along trails, on flat terrain, covered with a cape. Immediately after the transition in the rain (or in the snow), it is necessary to organize a bivouac, best of all in a shelter where you can make a fire, change clothes, and dry your wet clothes and shoes.

What to do during a thunderstorm

Particular care must be taken during thunderstorms. This weather phenomenon is associated with the development of cumulonimbus clouds and the accumulation of large electric charges. The greatest danger to humans is a direct lightning strike.

Lightning

Lightning is a giant electrical discharge that occurs between thunderclouds or between clouds and the ground. The currents generated in the ground during lightning strikes on the earth's surface are also dangerous.

Harbingers

Harbingers of a thunderstorm are powerful cumulonimbus clouds, multiple flashes of lightning, thunder. Just before the start of a thunderstorm, there is usually a lull or the wind changes direction, then suddenly the wind (swell) increases sharply and it begins to rain.

First measures

If you are on a hill when a thunderstorm approaches (on a ridge, hill, steep slope), you need to go down as quickly as possible to avoid being hit by lightning.

If you are in the water, you need to get ashore quickly.

In the forest, it is best to hide among low trees with dense undergrowth.

Remember that among trees, birch and maple are less susceptible to direct lightning strikes, and oak and poplar are the most susceptible.

We take cover

In open areas, you should choose sandy or rocky areas, you can hide in a dry hole, ditch, ravine.

In the mountains, it is undesirable to seek shelter from a thunderstorm in small grottoes (shallow caves with a wide entrance), rock pits, depressions, as there is a danger of being struck by currents formed in the ground after a lightning strike.

In a cave

If you still had to take refuge in a cave, grotto, large depression, you can’t be at the entrance or in the far corner of such a place, the position of a person is safe when the distance between him and the walls is at least 1 m.

Remember!

During a thunderstorm, do not:

be located next to the railway track, near a reservoir, near a tall object (tree);

lean head, back or other parts of the body against the surface of rocks, tree trunks;

stop at the edges of the forest and forest clearings.