Solar radiation and its influence on the human body
The sun is the source of heat and light, the giver of strength and health. However, not always its effect is positive. Lack of energy or excess can upset the natural processes of life and cause various problems. Many believe that tanned skin looks much more beautiful than the pale, however, if to spend a long time in direct light, you can get severe burns. Solar radiation is the flow of energy propagation in electromagnetic waves passing through the atmosphere. Knowing the effect of the sun on the person, it is possible to prevent its negative impacts.
What is a solar radiation
About the Sun and its energy written many books. The sun is the main source of energy of all the physical and geographic phenomena on Earth. One two-billionth fraction of light penetrates into the upper atmosphere of the planet, the greater part is deposited in the world space.
Rays of light – sources of other types of energy. Getting on the ground and in the water, they are formed in the heat affect climate and weather.
The impact of light rays on man depends on the level of radiation, as well as period spent under the sun. Many types of waves people use to their advantage, using x-ray radiation, infrared rays, and ultraviolet light. However, the solar waves in pure form in large quantities can negatively affect human health.
The amount of solar radiation depends on:
- the position of the Sun. The greatest amount of radiation falls on the plains and deserts, where the solstice is quite high, and the weather is cloudless. Polar regions receive the minimum amount of light as the cloud absorbs a significant portion of the light flux;
- the duration of the day. The closer to the equator, the longer the day. That's where people get more heat;
- properties of the atmosphere: cloud cover and humidity. At the equator, increased cloudiness and humidity, which impedes the passage of light. Therefore, the quantity of light there is less than in tropical zones.
Distribution
The distribution of sunlight on earth's surface is uneven and has a dependency on:
- the density and humidity of the atmosphere. The bigger they are, the less exposure;
- geographic latitude. The amount of received light increases from the poles to the equator;
- the motion of the Earth. The amount of radiation varies depending on the time of year;
- characteristics of the earth's surface. A large number of the luminous flux reflected by the bright surfaces such as snow. The most weakly reflects the light energy of the earth.
Because of the length of its territory the radiation level in Russia varies considerably. Solar irradiation in the Northern regions is 810 kWh/m2 per 365 days, in the South of 4100 kWh/m2.
It is important that the duration of hours during which the sun shines. These figures varied in different regions, which affects not only the geographical latitude and the presence of mountains. The solar radiation map of Russia shows clearly that in some regions it is not advisable to install lines of electricity as natural light is fully capable to meet the needs in electricity and heat.
Solar radiation: types
Light beams reach the Earth in different ways. It depends on the types of solar radiation:
- Coming from the sun is called direct radiation. Their strength depends on the height of the sun above the horizon level. The maximum level was observed at 12 hours a day minimum in the morning and the evening. In addition, the intensity of the impact has a relationship to the time of year: most occurs in summer, least in winter. It is characteristic that in the mountains the radiation level more than on flat surfaces. Also dirty air reduces direct light beams. The lower the sun above the horizon, the less ultraviolet radiation.
- The reflected radiation is radiation reflected by water or the ground.
- Diffuse solar radiation is formed when the dispersion of the luminous flux. It depends on the blue colour of the sky during cloudless weather.
The absorbed solar radiation depends on the reflectivity of the earth's surface – the albedo.
The spectral composition of radiation are diverse:
- colored or visible rays give light and are of great importance in the life of plants;
- the UV light must penetrate into the human body moderately, as its excess or lack can harm;
- infrared radiation gives the sensation of heat and affects the growth of vegetation.
Total solar radiation is penetrating the earth to direct and scattered rays. In the absence of clouds, about 12 o'clock, and in summer it reaches its maximum.
How is the impact
Electromagnetic waves consist of different parts. There is an invisible, infra-red and visible, ultraviolet rays. Characteristically, radiation fluxes have different energy and have different effects on people.
Luminous flux may have a beneficial, healingeffects on the human body. Passing through the visual organs, the light regulates the metabolism, sleep affects the overall health of the person. In addition, light energy can cause a feeling of warmth. Irradiation of the skin in the body there are photochemical reactions that promote proper metabolism.
High biological capability has ultraviolet light having a wavelength from 290 to 315 nm. These waves synthesize vitamin D in the body, and is also able to destroy the virus of tuberculosis for a few minutes, Staphylococcus in a quarter of an hour, sticks typhoid in 1 hour.
Characteristically, cloudless weather decreases the duration of emerging flu epidemics and other diseases, such as diphtheria, having the ability to spread by airborne droplets.
The natural power of the organism to protect people from sudden atmospheric fluctuations: temperature, humidity, pressure. Sometimes, however, such protection is weakened under the influence of strong humidity together with high temperatures leads to thermal shock.
The effect of irradiation has a relationship to the degree of its penetration into the body. The longer the wave, the stronger force of radiation. Infrared waves are able to penetrate up to 23 cm under the skin, visible flows up to 1 cm, ultraviolet rays – 0.5-1 mm.
All kinds of people get rays during solar activity when you are in open spaces. Light waves allow a person to adapt in the world, therefore, to provide a comfortable feeling in the premises it is necessary to create conditions for the optimal level of lighting.
Effects on humans
The influence of solar radiation on human health is determined by various factors. Matter the place of residence of the person, the climate, and the amount of time spent in direct light.
If there is insufficient sun in the far North residents, and people whose work involves underground, such as miners, there are various disorders of life, reduced bone strength, nerve disorders occur.
Children, loses light, suffer from rickets more often than others. In addition, they are more prone to diseases of the teeth and also have a longer course of TB.
However, too long exposure to light waves without periodic change of day and night can have a detrimental effect on health. For example, the inhabitants of the North often suffer from irritability, fatigue, insomnia, depression, decreased disability.
Radiation in the Russian Federation has a lower activity than, for example, in Australia.
Thus, people who are under prolonged radiation:
- exposed to a high probability of cancer of the skin;
- have an increased tendency to dryness of the skin, which in turn accelerates the aging process and the appearance of pigmentation, and early wrinkles;
- can suffer a deterioration of visual ability, cataract, conjunctivitis;
- have weakened immune systems.
Lack of vitamin D in humans is one cause of malignant neoplasms, metabolic disorders, leading to excessive body weight, endocrine disorders, sleep disturbances, physical exhaustion, bad mood.
The person who regularly receives the light of the sun and do not abuse solar baths, as a rule, is not experiencing health problems:
- has a stable work of the heart and blood vessels;
- not suffering with a nervous trouble;
- has a good mood;
- has a normal metabolism;
- rarely sick.
Thus, only a metered flow of radiation can have a positive impact on human health.
How to protect yourself
Excess exposure can provoke overheating of the body, burns, and exacerbation of certain chronic diseases. Lovers of sunbathing, care should be performing simple rules:
- with care to tanning outdoors;
- during the hot weather to hide in the shade under the scattered rays. This applies particularly to young children and the elderly suffering from tuberculosis and heart disease.
It should be remembered that sunbathing is necessary to a safe time of day, and not staying for a long time under the scorching sun. In addition, it should be protected from thermal shock head, wearing a hat, sunglasses, closed clothes and use different tools from the sun.
Solar radiation in medicine
Light is actively used in medicine:
- when x-rays are used the ability of waves to pass through soft tissue and the skeletal system;
- the introduction of isotopes enables you to fix their concentration in the internal organs, to detect many diseases and inflammation;
- radiation therapy can destroy the growth and development of malignant tumors.
Properties of waves are successfully used in many physiotherapeutic apparatuses:
- Devices with infra-red radiation thermotherapy is used for internal inflammatory processes, diseases of bones, osteoarthritis, rheumatism, thanks to the ability of waves to restore cellularstructure.
- Ultraviolet rays can affect living beings, to inhibit the growth of plants, to suppress micro-organisms and viruses.
Hygienic value of solar radiation is large. Apparatus with ultraviolet radiation used in the treatment of:
- various injuries of the skin: wounds, burns;
- infections;
- diseases of the oral cavity;
- cancer tumors.
In addition, radiation has a positive effect on the human body as a whole: can give strength, strengthen the immune system, to remedy the lack of vitamins.
Sunlight is an important source of valuable human life. Adequate intake leads to favorable existence of all living beings on the planet. Man can reduce the degree of radiation, but to protect themselves from its adverse effects.