About a third of our planet's population is sensitive to change environment. The biggest influence on a person's well-being is atmospheric pressure - gravity. air masses to Earth. What atmospheric pressure is considered normal for a person depends on the area in which he spends the vast majority of the time. Everyone will find their familiar conditions comfortable.
What is atmospheric pressure
The planet is surrounded by an air mass, which, under the influence of gravity, presses on any object, including the human body. The force is called atmospheric pressure. For each square meter crushes a column of air weighing approximately 100,000 kg. Atmospheric pressure is measured using a special device - a barometer. It is measured in pascals, millimeters of mercury, millibars, hectopascals, atmospheres.
The normal atmospheric pressure is 760 mm Hg. Art., or 101 325 Pa. The discovery of the phenomenon belongs to the famous physicist Blaise Pascal. The scientist formulated a law: at the same distance from the center of the earth (it doesn’t matter, in the air, at the bottom of a reservoir), the absolute pressure will be the same. He was the first to propose measuring heights using the barometric alignment method.
Atmospheric pressure standards by region
It is impossible to find out what atmospheric pressure is considered normal for a healthy person - there is no definite answer. The impact varies across different regions of the globe. Within relatively small area this value can vary markedly. For example, in Central Asia Slightly elevated numbers are considered standard (on average 715-730 mm Hg). For middle zone In Russia, normal atmospheric pressure is 730-770 mm Hg. Art.
Indicators are related to the elevation of the surface above sea level, wind direction, humidity and ambient temperature. Warm air weighs less than cold. Above the area with elevated temperature or humidity, the compression of the atmosphere is always less. People living in high mountain areas are not sensitive to such barometer readings. Their body was formed under these conditions, and all organs underwent appropriate adaptation.
How pressure affects people
The ideal value is 760 mmHg. Art. What awaits when the mercury column fluctuates:
- A change in optimal indicators (up to 10 mm/h) already leads to a deterioration in well-being.
- With a sharp increase or decrease (on average by 1 mm/h), even in healthy people there is a significant deterioration in health. Appears headache, nausea, loss of performance.
Meteor dependence
A person’s sensitivity to weather conditions – wind changes, geomagnetic storms – is called weather dependence. The influence of atmospheric pressure has not yet been fully studied. It is known that when changing weather conditions internal tension is created inside the vessels and cavities of the body. Meteorological dependence can be expressed:
- irritability;
- pain of various localization;
- exacerbation of chronic diseases;
- general deterioration of health;
- problems with blood vessels.
In most cases, people with the following diseases suffer from weather dependence:
- respiratory tract diseases;
- hypo- and hypertension.
Reaction to high blood pressure
A decrease in barometer readings by at least 10 units (770 mm Hg and below) has Negative influence to your health. People with long-standing cardiovascular and cardiovascular diseases are especially affected by weather changes. digestive system. Doctors on such days recommend reducing physical exercise, spend less time on the street, do not abuse heavy food and alcohol. Among the main reactions:
- feeling of congestion in the ear canals;
- decrease in the number of leukocytes in the blood;
- decreased activity of intestinal motility;
- dysfunction of the cardiovascular system;
- poor ability to concentrate.
Atmospheric air has a physical density, as a result of which it is attracted to the Earth and creates pressure. During the development of the planet, both the composition of the atmosphere and its atmospheric pressure changed. Living organisms were forced to adapt to the existing air pressure, changing their physiological characteristics. Deviations from average atmospheric pressure cause changes in a person’s well-being, and the degree of sensitivity of people to such changes varies.
Normal atmospheric pressure
The air extends from the surface of the Earth to heights of the order of hundreds of kilometers, beyond which interplanetary space begins, while the closer to the Earth, the more the air is compressed under the influence of its own weight, respectively, the atmospheric pressure is highest at earth's surface, decreasing with increasing altitude.
At sea level (from which all altitudes are usually measured), at a temperature of +15 degrees Celsius, the atmospheric pressure averages 760 millimeters of mercury (mmHg). This pressure is considered normal (from a physical point of view), which does not mean that this pressure is comfortable for a person under any conditions.
Atmosphere pressure measured by a barometer, graduated in millimeters of mercury (mmHg), or other units physical units, for example, in pascals (Pa). 760 millimeters of mercury corresponds to 101,325 pascals, but in everyday life the measurement of atmospheric pressure in pascals or derived units (hectopascals) has not taken root.
Previously, atmospheric pressure was also measured in millibars, which fell out of use and were replaced by hectopascals. Normal atmospheric pressure is 760 mm Hg. Art. corresponds to the standard atmospheric pressure of 1013 mbar.
Pressure 760 mm Hg. Art. corresponds to the action of a force of 1.033 kilograms on each square centimeter of the human body. In total, air presses on the entire surface of the human body with a force of about 15-20 tons.
But a person does not feel this pressure, since it is balanced by air gases dissolved in tissue fluids. This balance is disrupted by changes in atmospheric pressure, which a person perceives as a deterioration in well-being.
For some areas, the average atmospheric pressure differs from 760 mm. rt. Art. So, if in Moscow the average pressure is 760 mm Hg. Art., then in St. Petersburg it is only 748 mm Hg. Art.
At night, the atmospheric pressure is slightly higher than during the day, and at the Earth's poles, fluctuations in atmospheric pressure are more pronounced than at equatorial zone, which only confirms the pattern that the polar regions (Arctic and Antarctic) as habitats are hostile to humans.
In physics, the so-called barometric formula is derived, according to which, with an increase in altitude for every kilometer, atmospheric pressure drops by 13%. The actual distribution of air pressure does not follow the barometric formula quite accurately, since temperature, atmospheric composition, water vapor concentration and other indicators change depending on the altitude.
Atmospheric pressure also depends on the weather, when air masses move from one area to another. All living things on Earth also respond to atmospheric pressure. Thus, fishermen know that the standard atmospheric pressure for fishing is reduced, since when the pressure drops, predatory fish prefer to go hunting.
Impact on human health
Weather-dependent people, and there are 4 billion of them on the planet, are sensitive to changes in atmospheric pressure, and some of them can quite accurately predict weather changes, guided by their well-being.
It is quite difficult to answer the question of what standard of atmospheric pressure is most optimal for a person’s place of stay and life, since people adapt to life in different climatic conditions. Typically the pressure is between 750 and 765 mmHg. Art. does not worsen a person’s well-being; these atmospheric pressure values can be considered within the normal range.
When atmospheric pressure changes, weather-dependent people may feel:
- headache;
- vascular spasms with circulatory disorders;
- weakness and drowsiness with increased fatigue;
- joint pain;
- dizziness;
- feeling of numbness in the limbs;
- decreased heart rate;
- nausea and intestinal disorders;
- shortness of breath;
- decreased visual acuity.
Baroreceptors located in the body cavities, joints and blood vessels react first to changes in pressure.
When pressure changes, weather-sensitive people experience disturbances in the functioning of the heart, heaviness in the chest, pain in the joints, and in case of digestive problems, also flatulence and intestinal disorders. With a significant decrease in pressure, a lack of oxygen in brain cells leads to headaches.
Also, changes in pressure can lead to mental disorders - people feel anxiety, irritation, sleep restlessly, or generally cannot sleep.
Statistics confirm that with sudden changes in atmospheric pressure, the number of crimes, accidents in transport and production increases. The influence of atmospheric pressure on arterial pressure is traced. In hypertensive patients, increased atmospheric pressure can cause a hypertensive crisis with headache and nausea, despite the fact that at this moment clear sunny weather sets in.
On the contrary, hypotensive patients react more sharply to a decrease in atmospheric pressure. The reduced concentration of oxygen in the atmosphere causes circulatory disorders, migraines, shortness of breath, tachycardia and weakness.
Weather sensitivity can be a consequence of an unhealthy lifestyle. The following factors can lead to weather sensitivity or aggravate its severity:
- low physical activity;
- poor nutrition with accompanying excess weight;
- stress and constant nervous tension;
- poor state of the external environment.
Elimination of these factors reduces the degree of meteosensitivity. Weather-sensitive people should:
- include foods high in vitamin B6, magnesium and potassium in your diet (vegetables and fruits, honey, lactic acid products);
- limit the consumption of meat, salty and fried foods, sweets and spices;
- stop smoking and drinking alcohol;
- increase physical activity, take walks in the fresh air;
- organize your sleep, sleep at least 7-8 hours.
Atmospheric pressure measurement
According to generally accepted standards, it is customary to take millimeters of mercury as a unit for measuring pressure. Abbreviated as mm. rt. Art. To determine this, a device called a barometer is used. Barometers are divided into mercury and liquid-free. The second ones are called aneroid barometers. The barometer is represented by a glass tube, which is sealed on one side. Mercury is placed inside this tube. During the experiment, the open end of the tube is lowered into a vessel that is not completely filled with mercury. As the pressure rises or falls, the mercury in the tube begins to rise, and vice versa. The official unit of measurement is Pascal.Important! The kilopascal or kPa is the SI unit of mechanical stress pressure. Megapascal or MPa is a metric unit of measurement. If we convert these units, we get that 1 MPa is equal to 1000 kPa.
Atmospheric pressure standard
Atmospheric influence is considered normal when the air pressure is at sea level at latitude 45°. The temperature is 0 degrees Celsius. In 1644, thanks to Evangelista Torrencheli and Vincenzo Viviani, a value of 760 mm was obtained. It is worth noting that these discoverers were students of . A person feels most comfortable with standard values of 750-760 mm. rt. Art.However, these readings may not be completely accurate for all regions for a full year.
Increase and decrease in pressure
Atmospheric exposure increases when air pressure exceeds the norm of 760 mm. rt. Art. If it’s the other way around, it decreases.Over the course of 24 hours in the morning and evening, the pressure increases significantly.Low atmospheric exposure occurs in the afternoon and after midnight. These changes are due to temperature changes and air movement. There are 3 known zones on Earth where low atmospheric pressure predominates, and 4 belts with high atmospheric pressure. Due to the fact that the heat from the Sun and the rotation of the Earth occur unevenly, atmospheric pressure belts form on the globe. Over the course of a year, the Sun heats the Earth's hemispheres differently. Heating varies depending on what time of year it is.Important! Experts have identified a decline in atmospheric exposure in Moscow, which is 727 mm. rt. Art. In 2015, Moscow had an abnormal pressure of 778 mm. rt. Art. Plus, Moscow is located on the border of a vast cyclone, the central region of which is located over Latvia.
Impact on a person. Anticyclone
An anticyclone is an increase in barometric influence.During such periods, there is no significant wind outside, sunny weather prevails, and the temperature is not characterized by sudden changes. The humidity level remains normal. Anticyclone has a bad effect on human health. Changes in pressure have an adverse effect, especially on people with allergies, asthmatics and those with high blood pressure. arterial pressure. During an anticyclone, a person has a headache and also suffers from heart pain. It is believed that during such periods, performance decreases and malaise appears. Depending on the height of the anticyclone, effective or ineffective protection of the body from diseases is observed.Important! In order to make it easier to endure the anticyclone, experts recommend alternately dousing yourself with hot and cold water in the shower, eat more fruits that contain potassium, do light exercises. To improve the functioning of the immune system and nervous system It is necessary for a certain time to forget about serious matters that can undermine your health. On such days, a person suffering from negative symptoms should devote more time to rest to recuperate.
Cyclone
A cyclone is a period when the atmospheric influence decreases. The temperature during a cyclone rises, it becomes cloudy, humidity and precipitation levels increase, as well as during an anticyclone. During a cyclone, some groups of people cannot calmly tolerate changes in weather and pressure. Cyclone is poorly tolerated by people who have problems with respiratory functions, low blood pressure, as well as those with problems with the cardiovascular system. During a cyclone, the amount of oxygen decreases,As a result, it becomes difficult to breathe and shortness of breath appears. Patients complain of weakness. There is an increase in cerebral circulation, as a result of which a person suffers from migraines. No matter how many symptoms there are, experts advise drinking plenty of water and taking a contrast shower. It is also necessary for a person to get a good night's sleep. A favorite cup of coffee in the morning won't hurt. Regardless of whether your current blood pressure is known to be low or high, you need to drink tincture of lemongrass and ginseng.
Atmospheric pressure in the mountains
A man eager to conquer high mountains, knows that the hike may be unsafe. For example,an altitude of 3000 meters causes a decrease in performance, and at 6000 m a person can hardly survive. This is explained by the fact that the pressure decreases by half, the person lacks oxygen, and it is difficult for him to survive. However, it all depends on the climatic conditions in which the climber is located. If we take the humid maritime climate of Kamchatka, then a person will feel uncomfortable there even at an altitude of 1000 meters. Dry continental climate in the Himalayas allows the climber in most cases not to feel any difficulty when climbing up to 5000 meters. Different heights and their influence:- 5000 meters- there is a lack of oxygen, which can cause the climber to lose consciousness.
- 6000 meters- highest height for permanent human settlements.
- 8882 meters- height . Here a person adapted to such a height can live for several hours. At this altitude the boiling point will be +68 degrees Celsius.
- 13,500 meters- at approximately this altitude, a climber can survive by inhaling pure oxygen. This height is the maximum for survival without external protection.
- 20,000 meters- at this altitude a person dies almost immediately if he is outside the pressurized cabin.
Atmospheric pressure refers to the pressure of the thickness of atmospheric air on the surface of the Earth and objects located on it. The degree of pressure corresponds to the weight of atmospheric air with the base a certain area and configurations.
The main unit of measurement of atmospheric pressure in the SI system is Pascal (Pa). In addition to Pascals, other units of measurement are also used:
- Bar (1 Ba=100000 Pa);
- millimeter of mercury (1 mm Hg = 133.3 Pa);
- kilogram of force per square centimeter (1 kgf/cm 2 =98066 Pa);
- technical atmosphere (1 at = 98066 Pa).
The above units are used for technical purposes, with the exception of millimeters of mercury, which is used for weather forecasts.
The main instrument for measuring atmospheric pressure is the barometer. Devices are divided into two types - liquid and mechanical. The design of the first is based on flasks filled with mercury and immersed with the open end in a vessel with water. The water in the vessel transmits the pressure of the atmospheric air column to mercury. Its height acts as an indicator of pressure.
Mechanical barometers are more compact. The principle of their operation lies in the deformation of a metal plate under the influence of atmospheric pressure. The deforming plate presses on the spring, which, in turn, sets the arrow of the device in motion.
The influence of atmospheric pressure on the weather
Atmospheric pressure and its effect on weather conditions varies depending on place and time. It varies depending on the altitude above sea level. Moreover, there are dynamic changes associated with the movement of areas of high (anticyclones) and low pressure(cyclones).
Changes in weather associated with atmospheric pressure occur due to the movement of air masses between areas of different pressure. The movement of air masses is formed by wind, the speed of which depends on the difference in pressure in local areas, their scale and distance from each other. In addition, movements of air masses lead to temperature changes.
Standard atmospheric pressure is 101325 Pa, 760 mmHg. Art. or 1.01325 bar. However, a person can easily tolerate a wide range of pressures. For example, in the city of Mexico City, the capital of Mexico with a population of almost 9 million people, the average atmospheric pressure is 570 mm Hg. Art.
Thus, the value of the standard pressure is determined accurately. And comfortable pressure has a significant range. This value is quite individual and completely depends on the conditions in which you were born and lived. special person. Thus, a sudden movement from an area with relatively high pressure to an area of lower pressure can affect the work circulatory system. However, with prolonged acclimatization, the negative impact disappears.
High and low atmospheric pressure
In zones high pressure The weather is calm, the sky is cloudless and the wind is moderate. High atmospheric pressure in summer leads to heat and drought. In low pressure areas the weather is predominantly cloudy with wind and precipitation. Thanks to such zones, cool, cloudy weather with rain occurs in summer, and snowfall occurs in winter. The high pressure difference in the two areas is one of the factors leading to the formation of hurricanes and storm winds.
For normal atmospheric pressure, it is customary to take the air pressure at sea level at a latitude of 45 degrees at a temperature of 0°C. In these ideal conditions a column of air presses on each area with the same force as a column of mercury 760 mm high. This figure is an indicator of normal atmospheric pressure.
Atmospheric pressure depends on the altitude of the area above sea level. At higher elevations, the indicators may differ from ideal, but they will also be considered the norm.
Atmospheric pressure standards in different regions
As altitude increases, atmospheric pressure decreases. So, at an altitude of five kilometers, pressure indicators will be approximately two times less than below.Due to the location of Moscow on a hill, the normal pressure level here is considered to be 747-748 mm column. In St. Petersburg, normal pressure is 753-755 mm Hg. This difference is explained by the fact that the city on the Neva is located lower than Moscow. In some areas of St. Petersburg you can find a pressure norm of an ideal 760 mm Hg. For Vladivostok, normal pressure is 761 mmHg. And in the mountains of Tibet – 413 mmHg.
Impact of atmospheric pressure on people
A person gets used to everything. Even if the indicators normal pressure low compared to the ideal 760 mmHg, but are the norm for the area, people will.A person’s well-being is affected by sharp fluctuations in atmospheric pressure, i.e. decrease or increase in pressure by at least 1 mmHg within three hours
When pressure decreases, a lack of oxygen occurs in a person’s blood, hypoxia of body cells develops, and the heartbeat increases. Headaches appear. There are difficulties with the respiratory system. Due to poor blood supply, a person may experience pain in the joints and numbness in the fingers.
Increased pressure leads to an excess of oxygen in the blood and tissues of the body. The tone of blood vessels increases, which leads to their spasms. As a result, the body's blood circulation is disrupted. Visual disturbances may occur in the form of spots before the eyes, dizziness, and nausea. A sharp increase in pressure to large quantities may cause eardrum rupture.