What is atmospheric pressure. Low atmospheric pressure and relationship with well-being. How does our body react to high atmospheric pressure?

Many people are subject to change in environment. A third of the population is affected by gravity air masses to the ground. Atmospheric pressure: the norm for a person, and how deviations from the indicators affect the general well-being of people.

Changes in the weather can affect the human condition

What atmospheric pressure is considered normal for a person

Atmospheric pressure is the weight of air that presses on the human body. On average, this is 1.033 kg per 1 cubic cm. That is, 10-15 tons of gas control our mass every minute.

The norm of atmospheric pressure is 760 mmHg or 1013.25 mbar. Conditions in which the human body feels comfortable or adapted. In fact, the ideal weather indicator for any inhabitant of the Earth. In reality, everything is not so.

Atmospheric pressure is not stable. Its changes are daily and depend on the weather, relief, level above the sea, climate and even the time of day. Fluctuations are not noticeable to humans. For example, at night, the mercury column rises 1-2 divisions higher. Minor changes do not affect the well-being of a healthy person. Drops of 5-10 or more units are painful, and sharp significant jumps are fatal. For comparison: loss of consciousness from altitude sickness occurs already when the pressure drops by 30 units. That is, at the level of 1000 m above the sea.

A continent and even a separate country can be divided into conditional areas with different norms of average pressure. Because the optimal Atmosphere pressure for each person is determined by the region of permanent residence.

High air pressure adversely affects hypertension

Such weather conditions are generous for strokes and heart attacks.

Persons who are vulnerable to the vagaries of nature are advised by doctors on such days to stay outside the zone of active work and deal with the consequences of meteorological dependence.

Meteorological dependence - what to do?

The movement of mercury by more than one division in 3 hours is a reason for stress in a strong organism of a healthy person. Each of us feels such fluctuations in the form of a headache, drowsiness, fatigue. More than a third of people suffer from weather dependence in varying degrees of severity. In the zone of high sensitivity, the population with diseases of the cardiovascular, nervous and respiratory system, aged people. How to help yourself if a dangerous cyclone is approaching?

15 Ways to Survive a Weather Cyclone

Not much new advice has been collected here. It is believed that together they alleviate suffering and teach the right way of life with meteorological vulnerability:

1. See your doctor regularly. Consult, discuss, ask for advice in case of deterioration of health. Have your prescribed medications handy at all times.
2. Buy a barometer. It is more productive to track the weather by the movement of the mercury column, rather than knee pain. So you will be able to anticipate the impending cyclone.
3. Watch the weather forecast. Forewarned is forearmed.
4. On the eve of a change in weather, get enough sleep and go to bed earlier than usual.
5. Set up a sleep schedule. Get yourself a full 8-hour sleep, getting up and falling asleep at the same time. This has a powerful restorative effect.
6. The meal schedule is equally important. Follow a balanced diet. Potassium, magnesium and calcium are essential minerals. Overeating ban.
7. Drink vitamins in a course in spring and autumn.
8. Fresh air, walking outside - light and regular exercise strengthens the heart.
9. Don't overstress. Postponing household chores is not as dangerous as weakening the body before a cyclone.
10. Accumulate favorable emotions. Depressed emotional background feeds the disease, so smile more often.
11. Clothing made of synthetic threads and fur is harmful to static current.
12. store folk ways relieving symptoms in a prominent place. The recipe for herbal tea or compress is hard to remember when whiskey ache.
13. Office workers in high-rise buildings suffer from weather changes more often. Take a day off if possible, or better yet, change jobs.
14. A long cyclone is discomfort for several days. Is it possible to go to a quiet region? Forward.
15. Prevention at least a day before the cyclone prepares and strengthens the body. Do not give up!

Don't Forget to Take Vitamins for Health

Atmosphere pressure- This is a phenomenon that is absolutely independent of a person. Moreover, our body obeys him. What should be the optimal pressure for a person determines the region of residence. People with chronic diseases are especially susceptible to meteorological dependence.

All bodies in the universe have the property of being attracted to each other. Large and massive have more high strength attraction compared to small ones. This law is also inherent in our planet.


The earth attracts to itself any objects that are on it, including the gas shell surrounding it -. Although air is much lighter than the planet, it has big weight and presses on everything that is on the earth's surface. This creates atmospheric pressure.

What is atmospheric pressure?

Atmospheric pressure is understood as the hydrostatic pressure of the gas envelope on the Earth and objects located on it. At different heights and in different parts of the world, it has different indicators, but at sea level, 760 mm of mercury is considered standard.

This means that an air column of mass 1.033 kg exerts pressure on a square centimeter of any surface. Accordingly, there is a pressure of more than 10 tons per square meter.

People learned about the existence of atmospheric pressure only in the 17th century. In 1638, the Duke of Tuscany decided to embellish his gardens in Florence with beautiful fountains, but unexpectedly discovered that the water in the constructed structures did not rise above 10.3 meters.

Deciding to find out the reason for this phenomenon, he turned to the Italian mathematician Torricelli for help, who, through experiments and analysis, determined that air has weight.

How is atmospheric pressure measured?

Atmospheric pressure is one of the most important parameters of the Earth's gaseous envelope. Because in different places it differs; for its measurements, a special device is used - a barometer. An ordinary household appliance is a metal box with a corrugated base, in which there is no air at all.

When the pressure increases, this box contracts, and when the pressure decreases, on the contrary, it expands. Along with the movement of the barometer, a spring attached to it moves, which affects the arrow on the scale.

Weather stations use liquid barometers. In them, pressure is measured by the height of a mercury column enclosed in a glass tube.

Why does atmospheric pressure change?

Since the atmospheric pressure is created by the overlying layers of the gaseous envelope, as the height increases, it changes. It can be influenced by both the density of the air and the height of the air column itself. In addition, the pressure varies depending on the place on our planet, since different regions of the Earth are located at different heights above sea level.


From time to time, slowly moving areas of increased or reduced pressure. In the first case, they are called anticyclones, in the second - cyclones. On average, pressure at sea level ranges from 641 to 816 mm Hg, although inside it can drop to 560 mm.

How does atmospheric pressure affect the weather?

The distribution of atmospheric pressure over the Earth is uneven, which is primarily due to the movement of air and its ability to create the so-called baric vortices.

In the northern hemisphere, the clockwise rotation of air leads to the formation of descending air currents (anticyclones), which bring clear or slightly cloudy weather to a particular area with a complete absence of rain and wind.

If the air rotates counterclockwise, then ascending vortices are formed above the ground, characteristic of cyclones, with heavy precipitation, heavy winds, and thunderstorms. In the southern hemisphere, cyclones move clockwise, anticyclones move against it.

What effect does atmospheric pressure have on humans?

An air column weighing from 15 to 18 tons presses on each person. In other situations, such a weight could crush all living things, but the pressure inside our body is equal to atmospheric pressure, therefore, when normal at 760 mmHg we do not experience any discomfort.

If the atmospheric pressure is higher or lower than normal, some people (especially the elderly or sick) feel unwell, have a headache, and notice an exacerbation of chronic diseases.

Most often, a person experiences unpleasant sensations on high altitudes(for example, in the mountains), because in such areas the air pressure is lower than at sea level.

Atmospheric pressure - the pressure of the atmosphere on all objects in it and the Earth's surface. Atmospheric pressure is created by the gravitational attraction of air to the Earth.

In 1643, Evangelista Torricelli showed that air has weight. Together with V. Viviani, Torricelli conducted the first experiment on measuring atmospheric pressure, inventing the Torricelli tube (the first mercury barometer), a glass tube in which there is no air. In such a tube, mercury rises to a height of about 760 mm.

On the earth's surface, atmospheric pressure varies from place to place and over time. Especially important are the non-periodic changes in atmospheric pressure that determine the weather, associated with the emergence, development and destruction of slowly moving high-pressure areas (anticyclones) and relatively fast moving huge eddies (cyclones), in which low pressure prevails. There were fluctuations in atmospheric pressure at sea level within 684 - 809 mm Hg. Art.

Normal atmospheric pressure is a pressure of 760 mm Hg. Art. at sea level at 15°C. (International Standard Atmosphere - ISA) (101 325 Pa).

Atmospheric pressure decreases as altitude increases, since it is created only by the overlying layer of the atmosphere. The dependence of pressure on height is described by the so-called. barometric formula. The height to which one must rise or fall in order for the pressure to change by 1 hPa is called the baric (barometric) stage. Near the earth's surface at a pressure of 1000 hPa and a temperature of 0 °C, it is 8 m/hPa. With an increase in temperature and an increase in altitude above sea level, it increases, that is, it is directly proportional to temperature and inversely proportional to pressure. The reciprocal of the baric step is the vertical baric gradient, i.e., the change in pressure when raising or lowering 100 meters. At a temperature of 0 °C and a pressure of 1000 hPa, it is equal to 12.5 hPa.

On maps, pressure is shown using isobars - lines connecting points with the same surface atmospheric pressure, necessarily reduced to sea level. Atmospheric pressure is measured with a barometer.

In chemistry, the standard atmospheric pressure since 1982, according to the IUPAC recommendation, is a pressure of exactly 100 kPa.

air movement depends on the uneven heating of the earth's surface by the sun's rays. Due to the unequal accumulation of air masses and the difference in atmospheric pressure in various points Ascending and descending air currents arise on the earth's surface, which move air masses both horizontally and vertically. Wind speed (horizontal movement of air masses) is measured by the distance traveled by an air mass per unit of time and is expressed in meters per second (m/s).

It is widely used to determine the speed of air movement in points on the twelve-point Beaufort scale.

The speed of air movement varies considerably, from tenths of a meter to 30 or more meters per second during storms, snowstorms, hurricanes.

A characteristic feature of air movement is its unevenness, or turbulence, which depends on the presence of various obstacles and uneven terrain in the way of air movement, forest areas, settlements, etc.

The direction of the wind is determined by the point on the horizon from where the wind blows, and is indicated in rhumbs, by the letters of the Latin or Russian alphabet, respectively, the names of the countries of the world: north through C, or N, south through S, or S, east through B, or E, and west through W , or W.

In addition to the main points, the direction of the wind is also indicated by additional, or intermediate points: northeast through the NE, or NE, southeast through the SE, or SE, southwest through the SW, or SW, etc.

Wind direction varies both during the day and throughout the year. Moreover, at each point there is a known recurrence or frequency of the wind direction along the horizon points.

A graphic representation of the frequency of wind direction at a particular point is called a wind rose. The wind rose is compiled on the basis of determining wind directions over a long period of time (two years), and sometimes based on monthly and seasonal data.

Lines (rhumbs) are drawn from the center (point) in eight directions, and segments proportional to the frequency of winds are laid on each of them.

Calm days are indicated by a circle, the radius of which should correspond to the number of calm days. The ends of the segments are connected by lines and as a result a figure (closed) is obtained, which will be the wind rose.

The wind rose gives a visual representation of the predominance of one or another wind direction at a given point for a month, season, year.

Determining the wind rose or their frequency is of great hygienic importance, especially when planning livestock farms, relative position and the direction of the facade of the premises, the choice of places for camps and camps for animals in order to protect against harmful influence prevailing winds in the area.

Up to 30° northern latitude northeast winds prevail, from 30 to 60 ° - southwest and from 60 to 903 - again northeast.

In coastal and mountainous areas, local winds are observed: during the day from water to land, at night from land to sea; during the day from the plains to the mountains, at night from the mountains to the plains.

In the premises for animals, the air is in continuous and uneven movement.

The speed of air movement and its direction are determined by the presence of ventilation structures, the opening of gates and windows, the gaps in walls and ceilings, the release of heat by animals, etc.

IN winter period air speed in enclosed spaces for animals in the absence of defects in walls and ceilings at a height of 0.5 m from the floor, it fluctuates more often in the range of 0.05-0.25 m/s and rarely reaches 0.3 m/s. In autumn and spring, the air movement in the premises decreases somewhat, and in summer, with open windows and doors, it reaches 7 m / s.

The speed of air movement in the premises fluctuates more sharply in the end parts of the building and in the area where animals lie (in cowsheds).

Wind, as a weather factor, has an indirect and direct effect on the animal's body. The movement of air, together with its temperature and humidity, significantly affects the heat exchange of the animal organism. The higher the speed of air movement, the faster the change of its layers, directly adjacent to the skin. If the air temperature is lower than the temperature of the skin and buffer air in hairline, then the movement of air breaks the air shell, the cold mass of air comes into contact with the skin and contributes to increased heat transfer by convection and evaporation from the surface of the skin.

If the air temperature is higher than the skin temperature, then heat transfer by convection is weakened or stops; in these cases, if the air humidity is low, the heat transfer by evaporation increases.

The movement of air in the premises in summer from 0.3 to 1.6 m / s contributes to a better condition of the animals.

Experiments carried out during two summer seasons in University of California(USA), it was found that at an outside temperature of 31-32 in a corral with a fan, where the air speed reached 1.6 m / s, the gain of animals was 1075-1088 g per day per head, and in a corral, where the natural speed of movement air was on average 0.2 m / s, the weight gain was only 585-848 g with equal conditions feeding and drinking.

At low temperatures and high humidity, air mobility contributes to increased heat transfer through convection, heat conduction and heat radiation.

Thus, at high temperatures ah moving air (wind) protects animals from overheating, and at low increases the possibility of hypothermia.

Moderate winds have a favorable effect on animals, especially during the heat.

Cold and damp winds cause severe cooling and even freezing of animals. strong winds at high temperatures and dry air, they contribute to the burning of vegetation, saturate the air with dust, cause strong sweating and evaporation in animals, thirst, loss of appetite, constipation, decreased productivity, etc.

Cold and damp winds pose a great danger to animals and when they are kept indoors, when doors, windows are opened on both sides, or if there are gaps in the walls (drafts).

To protect animals from cooling during the cold season, strong air movement should not be allowed in the premises.

The maximum exchange of air in the premises of animals, if the air is not preheated, should not exceed 5 times the volume of the internal cubic capacity of the premises. The speed of air movement in the premises of animals in winter is desirable to maintain in the range from 0.05 to 0.25 m / s. However, the issue of optimal air movement rates in animal rooms has not been sufficiently developed and is subject to deeper study, taking into account various microclimatic conditions.

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LECTURE 3.

Atmosphere pressure

Physical properties of air

Change in pressure with height, Change in pressure horizontally. Isobars.

Pressure distribution near the Earth's surface

Wind.

Physical properties of air

On the surface of the earth and on all objects located near its surface, air creates pressure.

Consequently, on the entire surface of the human body, having an area of ​​​​1.6-1.8 m², this air, respectively, exerts a pressure of about 16-18 tons. Usually we do not feel this, because under the same pressure gases are dissolved in the fluids and tissues of the body and from the inside balance the external pressure on the surface of the body.

However, when the external atmospheric pressure changes due to weather conditions it takes some time to balance it from the inside, necessary to increase or decrease the amount of gases dissolved in the body. The changing pressure in the accessory cavities of the skull promotes blood circulation in the brain. Changes in pressure difference between external environment and closed body cavities affect the human condition. During this time, a person may feel some discomfort, because when the atmospheric pressure changes by only a few mm Hg.

Art. the total pressure on the surface of the body changes by tens of kilograms. These changes are especially clearly felt by people suffering from chronic diseases of the musculoskeletal system, cardiovascular systems s and others. A decrease in atmospheric pressure acts on the sympathetic nervous system; suppresses mood, reduces efficiency, increases susceptibility to infectious diseases.

Conversely, its increase excites in more nervous system.

Main physical properties air: density, pressure, temperature.

Density is the ratio of the mass of a substance to its volume. 1 m3 of water at a temperature of 4°C has a mass of 1 ton, and 1 m3 of air at 0°C and normal pressure (760 mm Hg).

Art.) has a mass of 1.293 kg. Therefore, under these conditions, the density of water is 1000 kg/m3, and the density of air is 1.293 kg/m3. Thus, the density of air is about 800 times less than the density of water.

The density of the atmosphere decreases rapidly with height.

Half of the entire mass of the atmosphere is concentrated in a layer up to a height of 5.5 km.

atmospheric pressure is the force with which a column of air pushes on a unit of the earth's surface, extending from the surface of the earth to upper bound atmosphere. Atmosphere pressure for a long time expressed in millimeters (mm) of mercury.

That is, the force was measured with a linear measure, which was inconvenient when solving many problems. In practice, 1/1000 of a bar is used as a unit of pressure. millibar . At sea level, the height of the mercury column in the tube is usually about 760 mm. The value of 760 mm was first obtained in 1644 by Evangelista Torricelli (1608-1647) and Vincenzo Viviani (1622-1703) - students of Italian scientist Galileo Galileo.

1 mb (millibar) = 1 Gpa (gigapascal) = 0.75 mmHg

Art. (rounded 3/4 mmHg)

Atmosphere pressure. Change and impact on the weather

1 mmHg Art. = 1.33 mb = 1.33 GPa (rounded 4/3 mb).

The baric stage is the vertical distance that must be raised or lowered in order for the pressure to change by 1 mb.

Temperature . The higher the temperature, the lower the air density. In the case of constant pressure, the density of the air depends on the change in temperature. As the flight altitude increases, the pressure decreases and the temperature decreases.

The pressure decreases faster than the temperature. Lowering the temperature somewhat slows down the decrease in density. Air density decreases more slowly with height than pressure.

Pressure distribution near the Earth's surface

The pressure on the globe can vary widely.

So, the maximum value of atmospheric pressure is 815.85 mm Hg. Art. (1087 mb) registered in winter in Turukhansk, the minimum is 641.3 mm Hg. Art. (854 mb) — in Hurricane Nancy over the Pacific Ocean.

Air pressure on our planet can vary widely.

If the air pressure is greater than 760 mm Hg. Art., then it is considered increased, less - reduced.

Atmospheric pressure rises twice during the day (morning and evening) and falls twice (after noon and after midnight). These changes are associated with changes in temperature and air movement. During the year on the continents, the maximum pressure is observed in winter, when the air is supercooled and compacted, and the minimum pressure is observed in summer.

The distribution of atmospheric pressure over the earth's surface has a pronounced zonal character.

This is due to uneven heating of the earth's surface, and consequently, a change in pressure.

On the globe, there are three belts with a predominance of low atmospheric pressure (minimums) and four belts with a predominance of high pressure (maximums).

In the equatorial latitudes, the surface of the Earth warms up strongly.

The heated air expands, becomes lighter and therefore rises. As a result, low atmospheric pressure is established near the earth's surface near the equator.

At the poles, under the influence of low temperatures, the air becomes heavier and sinks.

Therefore, at the poles, atmospheric pressure is increased by 60-65 ° compared to latitudes.

In the high layers of the atmosphere, on the contrary, over hot areas the pressure is high (although lower than at the Earth's surface), and over cold areas it is low.

The general scheme for the distribution of atmospheric pressure is as follows: along the equator there is a belt low pressure; at 30-40 ° latitude of both hemispheres - high pressure belts; 60-70 ° latitude - low pressure zones; in the polar regions - areas of high pressure.

As a result of the fact that in temperate latitudes In the northern hemisphere in winter, atmospheric pressure over the continents rises sharply, the low pressure belt is interrupted.

It persists only over the oceans in the form of closed areas of low pressure - the Icelandic and Aleutian lows. Over the continents, on the contrary, winter maxima are formed: Asian and North American.

General atmospheric pressure distribution scheme

In summer, in the temperate latitudes of the Northern Hemisphere, the low atmospheric pressure belt is restored. A huge area of ​​low atmospheric pressure centered on tropical latitudes- Asian low - formed over Asia.

In tropical latitudes, the continents are always hotter than the oceans, and the pressure over them is lower.

Thus, over the oceans throughout the year there are maxima: North Atlantic (Azores), North Pacific, South Atlantic, South Pacific and South Indian.

The formation of atmospheric pressure belts near the earth's surface is influenced by the uneven distribution solar heat and the rotation of the earth. Depending on the season, both hemispheres of the Earth are heated by the Sun in different ways. This causes some movement of atmospheric pressure belts: in summer - to the north, in winter - to the south.

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The norm of atmospheric pressure for a person

The norm of atmospheric pressure for a person is 760 millimeters of mercury.

Atmosphere pressure

If we translate this value into units of measurement that are more understandable for a simple layman, it turns out that the mass of the air column above each square meter the earth's surface is 10,000 kilograms! Impressive, isn't it? The dense airy "blanket" that envelops our planet has powerful pressure on all objects near us and on ourselves.

How does a person manage to cope with such a huge load?

The fact is that air presses on objects from all sides. The forces are balanced, and we do not feel any discomfort. However, this rule only works on the earth's surface. The human body is adapted to exist under just such pressure, so if it plunges into water or climbs to the top of a mountain, it will feel unwell.

However, sometimes people do not feel well under normal conditions.

Over the continents, atmospheric pressure rises during periods of high humidity: in spring, autumn and winter, as water drops in the air make it heavier.

In summer, during dry weather, atmospheric pressure above the earth's surface in the interior of the continents usually decreases as the air becomes drier. Temperature also affects atmospheric pressure. As is known, warm air lighter than cool. Much also depends on geographical location and altitude above sea level.

Since people are born and live in various parts of the planet and at various altitudes, it is impossible to say that there is an ideal atmospheric pressure for a person.

Normal atmospheric pressure for a person

The optimal atmospheric pressure for a person is the pressure to which he has adapted well, living in a particular area under certain climatic conditions.

For example, the normal atmospheric pressure for a person in Moscow will be 748 millimeters of mercury. Art. To the north, for example, in St. Petersburg, this value will be 5 mm Hg more.

The difference is easily explained: Moscow is located on a hill and, compared to St. Petersburg, is somewhat higher above sea level. Indicative in this example will be Tibet, where normal pressure air for a person is 413 millimeters of mercury. Art., although for tourists from the same Moscow to live in such conditions will be quite difficult.

That is why it is possible to determine which atmospheric pressure is considered elevated and which atmospheric pressure is considered reduced, only in relation to a specific person.

Changes in atmospheric pressure affect weather-dependent people, of whom there are about 4 billion today.

Sharp fluctuations cause a deterioration in health and the following symptoms:

• irritability, headache and drowsiness;
• increased blood clotting;
• numbness of the limbs, joint pain;
• breathing difficulties and heart palpitations;
• increased vascular tone and their spasms, circulatory disorders;
• visual impairment;
• nausea and dizziness;
• an excess of oxygen in the tissues and blood;
• rupture of the eardrum;
• problems with the gastrointestinal tract.

As a rule, fluctuations in atmospheric pressure are accompanied by changes in weather conditions, which is why weather-dependent people feel bad before precipitation, storms, and thunderstorms.

That is why the importance of atmospheric pressure for a person is very important.

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How pressure affects people

Atmospheric pressure over 760 millimeters of mercury. Art. considered elevated. Many of these changes feel unsettled. It is especially noticeable in people with various neuropsychiatric diseases.

In some European countries the police keep a close eye on fluctuations in atmospheric pressure, as the number of offenses begins to increase on such days and hours.

More is happening at this time car accidents because the reaction speed of drivers is reduced. The concentration of attention worsens, as a result of which there is an increased risk of various kinds emergencies in production and industrial disasters associated with the human factor. Most often on such days, people suffer from insomnia.

Hypotonic patients feel bad: the pressure decreases, breathing becomes deep, the pulse quickens.

Problems with the gastrointestinal tract begin, as peristalsis decreases.

Low atmospheric pressure and well-being

Low atmospheric pressure is considered to be below 760 mm Hg.

Art. A sharp decrease in pressure is dangerous for hypertensive patients and people suffering from atherosclerosis, since at such moments oxygen starvation begins, an increase in the number of blood cells and blood thickening occurs. The cardiovascular system begins to work under conditions of increased stress, which leads to an increase in blood pressure, arrhythmia, and an increase in heart rate.

This affects the elderly. On such days, the number of strokes and heart attacks increases.

Headaches and migraines occur, which are often impossible to remove with pills. With a sharp decrease in atmospheric pressure, the risk of asthma attacks in asthmatics and allergy sufferers increases.

Less sensitive, younger and relatively healthy people feel drowsiness and lack of energy.

Ideal atmospheric pressure for a person and recommendations from doctors

Most often, people suffering from weather dependence are overweight.

Also, those who poorly monitor the state of their body, move little, watch TV for a long time or work at a computer, and have reduced immunity are also susceptible to this ailment. For them, even slight deviations can be noticeable. At the same time, normal weather pressure for a person cannot be maintained even during the day, since it decreases in the morning and evening.

To get rid of weather dependence, first of all, you need to eat right. Vitamin B6, potassium and magnesium will help to cope with reactions to weather changes, strengthen the cardiovascular system, support the nervous system and reduce sensitivity during overload. It is also recommended to reduce the load on the body and switch to a diet with a reduced meat content.

It is necessary to monitor your diet, avoid eating fatty, fried, sweet, salty foods. Refusing spices for a while will also not be superfluous. It is known, for example, that hot red pepper can increase blood pressure. Strengthen meteorological dependence nicotine and alcohol.

At times of change in weather and changes in atmospheric pressure, it is worth abandoning unnecessary physical exertion: cycling, jogging, excessive work on suburban area etc.

In the fight against weather dependence help:

• physiotherapy. For example, hardening procedures can be carried out even at home. The blood vessels and nervous system will be strengthened by a contrast shower, cold water rubdowns, swimming in the pool, mud procedures and therapeutic baths.

  Massage and acupuncture will undoubtedly help to relax;

• regular classes in various types of gymnastics: yoga, qigong, tai chi, etc.
• walks every day fresh air, departure for nature and a relaxing holiday;
• the correct mode of the day, sleep and wakefulness, work and rest;
• taking care of your mental health and nervous system, creating a favorable atmosphere around.

To maintain health, there are natural preparations: ginseng, deer antler extract, eleutherococcus, honey and bee products.

However, before taking natural supplements, you should always consult with your doctor.

Those suffering from meteorological dependence should listen more to their body and try to take care of their health, and then any barometer readings will mean good atmospheric pressure for a person.

§ 31. Atmospheric pressure (textbook)

§ 31.Atmospheric pressure

Remember from the course of natural history what is called atmospheric pressure.

The concept of atmospheric pressure. Air is invisible and light.

However, it, like any substance, has mass and weight. So it puts pressure on earth's surface and on all bodies, they are on it. This pressure is determined by the weight of an air column as high as the entire atmosphere - from the earth's surface to its uppermost boundary. It has been established that such an air column presses on every 1 cm2 of the surface with a force of 1 kg 33 g (more than 10 tons per 1 m2, respectively!) So, Atmosphere pressure- This is the force with which air presses on the earth's surface and on all objects on it.

The surface of the human body is on average 1.5 m2. According to the air, press on it with a weight of 15 tons.

Such pressure can crush all living things. Why don't we feel it? This is due to the fact that the intrahuman body also has pressure - internal, and it is equal to atmospheric pressure. If this balance is disturbed, a person feels bad.

Measurement of atmospheric pressure. Atmospheric pressure is measured using a special device - a barometer. Translated from Greek, this word means "Gravity meter".

Weather stations use mercury barometer.

Its main part is a glass tube 1 m long, sealed at one end. Mercury is poured into it - a heavy liquid metal. The open end of the tube is immersed in a wide bowl, also filled with mercury. When turned over, the mercury from the tube spilled out only to a certain level and stopped. Why did it stop, and not pour out all? Because the air puts pressure on the mercury in the bowl and does not let it all out of the tube. If the atmospheric pressure decreases, then the mercury in the tube goes down and vice versa.

The height of the mercury column in the tube, on which the scale is applied, determines the value of atmospheric pressure in millimeters.

At parallel 450 at sea level at an air temperature of 0 0C, under air pressure, a column of mercury rises in the tube to a height of 760 mm.

This air pressure is considered normal atmospheric pressure. If the column of mercury in the tube rises above 760 mm, then the pressure elevated, Below - lowered.Consequently, the pressure of the air column of the entire atmosphere is balanced by the weight of the mercury column 760 mm high.

On hikes and expeditions, they use a more convenient device - aneroid barometer"Aneroid" in Greek means "ridineless": it does not contain mercury.

Its main part is a metal elastic box, from which air was downloaded. This makes it very sensitive to pressure changes from outside. When pressure is increased, it contracts; when pressure is reduced, it expands. These fluctuations through a special mechanism are transmitted to the arrow, which indicates on the scale the value of atmospheric pressure in millimeters of mercury.

The dependence of pressure on the height of the terrain and air temperature. Atmospheric pressure depends on the height of the area.

The higher the sea level, the lower the air pressure. It decreases, because with the rise, the height of the air column that presses on the earth's surface decreases. In addition, pressure also decreases with height because the density of the air itself decreases. At an altitude of 5 km, atmospheric pressure is reduced by half compared to normal pressure at sea level.

In the troposphere, with every 100 m rise, the pressure decreases by about 10 mm Hg. Art.

Knowing how pressure changes, it is possible to calculate both the absolute and relative height of a place. There is also a special barometer - altimeter, In which, along with the scale of atmospheric pressure, there is also a scale of heights.

So, each area will have its own normal pressure: at sea level - 760 mm Hg, in the mountains, depending on the height - lower. For example, for Kyiv, lying at an altitude of 140-200 m above sea level, the average pressure will be 746 mm Hg. Art.

Atmospheric pressure also depends on air temperature. When heated, the volume of air increases, it becomes less dense and light. For this, atmospheric pressure also decreases.

On cooling, the opposite occurs. Consequently, with a change in air temperature, the pressure also changes continuously. During the day, it rises twice (in the morning and in the evening) and decreases twice (after noon and after midnight).

In winter, when the air is cold and heavy, the pressure is higher than in summer, when it is warmer and lighter. So, for a change in pressure, you can predict changes in the weather.

A decrease in pressure indicates precipitation, an increase indicates dry weather. Changes in atmospheric pressure affect people's well-being.

Distribution of atmospheric pressure on the Earth. Atmospheric pressure, like air temperature, is distributed on Earth in bands: there are zones of low and high pressure.

Their formation is associated with heating and air movement.

Above the equator, the air warms up well. From this it expands, becomes less dense, and therefore lighter.

Lighter than air rises up - happens upward movement air. Therefore, there, at the surface of the Earth, the course of the year is established low pressure belt.

What is the relationship between atmospheric and blood pressure?

Above the poles, where temperatures are low throughout the year, the air cools, becomes denser and heavier. So it goes down - happens downward movement air and the pressure increases. Therefore, the upoles formed high pressure belts. The air rising above the equator spreads towards the poles. But, before reaching them, at a height it cools, becomes heavier and descends at the 30-350 parallels in both hemispheres.

As a result, there are formed high pressure belts. In temperate latitudes, on the parallels 60-650 of both hemispheres, low pressure belts.

Thus, there is a close dependence of atmospheric pressure on the distribution of heat and air temperatures on Earth, when ascending and descending air movements cause uneven heating of the earth's surface.

Questions and tasks

Determine how much the air in the classroom weighs if its length is 8 m, width 6 m, height 3 m.

2. Why does atmospheric pressure decrease with altitude?

3. Why does the pressure change in the same place? How does this change in air temperature affect?

4. Determine approximately the relative height of the mountain peak, if the barometer shows 720 mm at the foot of the mountain, and 420 mm at the top.

How is atmospheric pressure distributed on Earth?

6. Remember which absolute height your area. Calculate which barometric pressure can be considered normal for your area.

Measurement of atmospheric pressure. Torricelli's experience - Kasyanov, Dmitrieva, 7th grade.

1. Why is it impossible to calculate atmospheric pressure using the formula p = gρh?
Because

you need to know the height of the atmosphere and the density of the air.

2. What contribution to science did Evangelista Torricelli (1608–1647) make?
Allowed to measure atmospheric pressure.

3. Why is the pressure of mercury in the tube at the level aa1 equal to atmospheric pressure?

The pressure in the tube at the level aa1 is created by the weight of the mercury column in the tube, since there is no air above the mercury in the upper part of the tube.

It follows that the atmospheric pressure is equal to the pressure of the mercury column in the tube.

4. What is the ratio between 1mm. rt. Art. and pascal (Pa)?
1 mm. rt. Art. = 133.3 (Pa)
1 Pa = 0.0075 mm. rt.

5. Atmospheric pressure is 750 mm. rt. Art. What does it mean?
99975 Pa

6. What is the reason for the change in atmospheric pressure?
With the change of the weather

What does atmospheric pressure depend on?

A device for measuring atmospheric pressure is a mercury barometer (from the Greek baros - gravity, metreo - I measure).

8. The weather report announced that the pressure p = 750 mm. rt. Art. Express this pressure in hectopascals (hPa).

9. Why does an aluminum canister deform after being evacuated?

External pressure is greater than internal.

What forces prevent the rupture of the Magdeburg hemispheres?

Inside the vacuum, so on them with huge force atmospheric pressure acts - it prevents them from breaking.

11. Why do passengers often get "stuffed" ears when taking off and landing planes?
With the rise, atmospheric pressure increases, to which a person is not accustomed.

12. What is the study of atmospheric pressure connected with?
Due to consumer needs, pumps were invented, with the help of which they wanted to raise water to a great height, but atmospheric pressure was not studied, they did not know about its existence.

What role did Galileo play in the study of atmospheric pressure?
They turned to Galileo for advice. Galileo examined the pumps and found that they were in good order. Having dealt with this issue, he pointed out that pumps cannot raise water higher than 18 Italian cubits (≈10 m).

14. What conclusion did Torricelli make as he continued Galileo's research?
The real reason for the mercury rising in the tube is air pressure, not "fear of the void."

This pressure produces air by its weight. (And that air has weight was already proven by Galileo.)

15. What is the essence of Pascal's experience, which he called the proof of emptiness in emptiness?
The French scientist Pascal learned about Torricell's experiments. He repeated Torricelli's experiment with mercury and water. However, Pascal believed that in order to finally prove the fact of the existence of atmospheric pressure, it is necessary to do the Torricelli experiment once at the foot of a mountain, and another time at its top, and in both cases measure the height of the mercury column in the tube.

If the column of mercury at the top of the mountain were lower than at its foot, then one would have to conclude that the mercury in the tube is indeed supported by atmospheric pressure.

Some people's well-being depends on the weather. At normal atmospheric pressure, their condition remains stable, but with any changes, its deterioration is observed.

What is atmospheric pressure?

Atmospheric pressure is the mass of air that presses on the human body. The average is 1.033 per 1 cm³. From this it follows that every minute the mass of the body is controlled by 10-15 tons of gaseous matter.

The normal value is 1013.25 mbar or 760 mmHg. Art. In such conditions, the body is not subject to any negative effects.

What does it depend on?

The pressure indicator is not stable. It changes every day depending on the location of the area above sea level, topography, climate, weather conditions. There are other factors that affect atmospheric pressure. These fluctuations cannot be noticed. For example, at night, the barometer column increases by 1-2 divisions.

Minor changes do not affect the state of human health. If the differences reach 5-10 units, there is a deterioration in well-being. In addition, significant pressure surges can cause death.

Atmospheric pressure is measured using thermohygrometers and barometers. For this purpose, the following measuring units are used:

• mmHg Art. (millimeters of mercury);
• Pascals;
• bars;
• kgf/cm²;
• atmosphere.

What atmospheric pressure is considered normal for a person?

The standard is considered to be 760 mm. rt. Art. These norms for a person may differ depending on the living conditions. For example, in Mexico City, the pressure does not rise above 570 mm Hg. Art., because The capital of Mexico is located high above sea level. People who live in this area find it difficult to tolerate other conditions. It follows from this that the normal atmospheric pressure indicator is individual for each region and is determined by the familiar environment.

What effect does it have on a person?

atmospheric and arterial pressure has a close relationship. A decrease in barometer values ​​leads to the following negative manifestations:

• respiratory failure;
• decrease in heart rate;
• apathy and a feeling of drowsiness;
• decrease in blood pressure;
• increased fatigue;
• headache;
• dizziness;
• nausea;
• digestive disorders;
• impaired concentration.

In the risk category are people with pathologies of the respiratory system and hypotension. Their condition worsens under such conditions. If no negative changes are observed, then such atmospheric pressure is considered normal for a person.

Elevated blood pressure can also cause a disturbance in well-being. In this case, the signs will be different:

• dizziness;
• buzzing in the ears;
• increase in blood pressure;
• sensation of pulsation in the temples;
• redness of the skin of the face;
• increased heart rate;
• "sparkles" before the eyes;
• headache;
• urge to vomit.

In conditions increased rates barometer, heart attacks and strokes often occur. For people prone to meteorological dependence, medical experts recommend avoiding stress and vigorous activity during this period.

What is weather dependence?

If mercury passes more than 1 barometer division in 3 hours, this causes significant stress even for a healthy organism. Such jumps are manifested in the form of fatigue, drowsiness and migraines. Meteorological dependence is the sensitivity of people to changes in weather conditions. About 1/3 of the world's population faces this problem. The risk group includes people with pathologies of the respiratory, nervous and cardiovascular systems, as well as elderly patients.

To minimize the negative impact of a meteorological cyclone, it is necessary to adhere to the following recommendations:

1. Even if a normal atmospheric value prevails in the area, you need to regularly undergo medical consultations. At the same time, it is always necessary to have medicines prescribed by the doctor at hand.
2. To track weather changes, it is recommended to purchase a barometer. So you can take timely measures to minimize discomfort.
3. Before the expected weather changes, it is recommended to go to bed earlier than usual. A full sleep lasts 8 hours. This allows you to achieve maximum restorative action.
4. It is also important for people with weather dependence to eat on schedule. In this case, the diet should be balanced. It should include as many products as possible, which contain a lot of calcium, magnesium, potassium.
5. Additionally, you can use vitamin complexes, especially in autumn and spring.
6. Walking outside and moderate physical exercise strengthen the heart muscle.
7. Stress should be avoided. Postponing household chores is better than exhausting the body before an approaching meteorological cyclone.
8. Positive way. If a person is depressed emotionally, it feeds the disease.
9. Clothing items made of synthetics and fur generate static electricity, which can worsen the condition of weather-dependent people.
10. People who work in high-rise buildings are much more likely to suffer from climate change. If possible, it is better to take a day off. If the state of health worsens frequently, it is recommended to change jobs.
11. A prolonged meteorological cyclone predicts discomfort for 2-3 days. If possible, it is better to leave for a quieter area for this period.

It should also be understood that meteorological dependence has a secondary character. Climatic conditions only expose the vulnerabilities of the body. For example, if a person does not have problems with bones and joints, they will not hurt when blood pressure rises or changes.

Pressure standards in different regions of the country

Atmospheric pressure in different areas of the state is different. At the same time, the inhabitants of the mountainous area are immune to changes in temperature and humidity, because. they grew up in such conditions and adapted to them.

Table “Normal atmospheric pressure for Russian regions”

Russia is a large state, therefore, different regions have their own standard of atmospheric index. Exists climate map, which displays the average values.

Deviations in the pressure value for Russian regions are shown in the table.

Atmospheric pressure is mentioned even in weather forecasts, but what is its nature? What determines low and high atmospheric pressure? How does its change affect human health?

What it is?

Back in 1638, people had little idea that such a phenomenon even existed, until the Duke of Tuscany decided to decorate Florence with fountains on high altitude. His attempt failed miserably, as the water did not rise above ten meters. Then it was time for the first experiments in this area.

With the development of science, it became clear that pressure is a physical quantity that reports the amount of force applied perpendicular to a unit area of ​​any surface. The atmosphere is no exception. It presses on our planet with the help of air, which is present everywhere.

The mass of the air around us is millions of times less than the earth's, but this is quite enough for all objects and beings to experience its influence. About fifteen tons of air presses on us every day, but we cannot feel it, because the internal pressure of the human body is the same as atmospheric pressure.

Low and high atmospheric pressure

Like any physical quantity, the pressure can be measured. IN international system units for this use pascal (Pa), in Russia they also use bars and millimeters of mercury.

The average value is taken at a temperature of zero degrees at sea level at a latitude of 45 degrees. It is designated as normal atmospheric pressure and is 760 millimeters of mercury or 101325 pascals.

What does atmospheric pressure depend on? First of all, on the amount of air per unit area: the less it is, the lower the pressure and vice versa. It directly depends on the height. At higher altitudes, the air is thinner, so its value decreases with elevation. At an altitude of 5 km, its strength is only two times less, at an altitude of 20 km - about 18 times.

The pressure tends to change different time days and seasons. An important factor is the temperature. At night, when the temperature drops, the pressure is slightly lower than during the day. On the continents, high atmospheric pressure is observed in winter, low - in summer.

Pressure zoning

Areas globe are heated differently, as a result, the distribution of pressure occurs zonal. In some places, the air heats up and reduces its pressure. Rising up and gradually cooling, it moves to neighboring areas, increasing the pressure there.

A similar redistribution of air masses is clearly seen in equatorial belt, where, due to high temperatures, the pressure is always low, and in neighboring tropical zones it is usually elevated. In Antarctica and the North Pole, constant high pressure is a consequence of the influx of air from temperate latitudes.

As mentioned above, pressure is characterized by seasonal fluctuations, but these changes are not very significant. In general, pressure indicators are stable: there are constantly zones of high and low pressure on the planet.

Influence of high atmospheric pressure

A person can feel the power of this phenomenon on himself, climbing the mountains. Many people are familiar with laying their ears when you overcome sometimes minor climbs. You can feel it by diving deep under the water, by the way, maximum depth such a dive without special equipment is no more than 170 meters (although this is quite risky).

IN Everyday life a person also feels changes in pressure, especially if there are sharp drops. High atmospheric pressure is accompanied by clear weather and dryness, harmful substances in the air are felt more sharply. As a result, allergies and respiratory problems are exacerbated.

An increase in pressure is clearly reflected in the well-being of hypertensive patients. By helping to reduce white blood cells in the blood, it can weaken the immune system. Therefore, during periods of high blood pressure, it is more difficult for a person to fight infections and other diseases.