The sun is a star solar system, which is a source of enormous amounts of heat and blinding light. Despite the fact that the Sun is at a considerable distance from us and only a small part of its radiation reaches us, this is quite enough for the development of life on Earth. Our planet revolves around the sun in an orbit. If with spaceship observe the Earth during the year, it can be seen that the Sun always illuminates only one half of the Earth, therefore, there will be day, and at that time there will be night on the opposite half. The earth's surface receives heat only during the day.
Our Earth is heating unevenly. The uneven heating of the Earth is explained by its spherical shape, so the angle of incidence of the sun's ray in different areas is different, which means that different parts of the Earth receive different quantity heat. At the equator, the sun's rays fall vertically, and they strongly heat the Earth. The farther from the equator, the angle of incidence of the beam becomes smaller, and consequently, these territories receive less heat. The same power beam solar radiation heats a much smaller area, as it falls vertically. In addition, rays falling at a smaller angle than at the equator, penetrating through, travel a longer path in it, as a result of which part of the sun's rays are scattered in the troposphere and do not reach the earth's surface. All this indicates that when moving away from the equator to the north or south, it decreases, since the angle of incidence of the sun's ray decreases.
The degree of heating of the earth's surface is also affected by the fact that the earth's axis is inclined to the plane of the orbit, along which the Earth makes a complete revolution around the Sun, at an angle of 66.5 ° and is always directed by the northern end towards the Polar Star.
Imagine that the Earth, moving around the Sun, has the Earth's axis perpendicular to the plane of the orbit of rotation. Then the surface would different latitudes would receive a constant amount of heat throughout the year, the angle of incidence of the sun's ray would be constant all the time, it would always be day equals night there would be no change of seasons. At the equator, these conditions would differ little from the present. Significant effect on the heating of the earth's surface, and hence on the entire slope earth's axis has in temperate latitudes.
During the year, that is, during full turn Earth around the Sun, four days are especially remarkable: March 21, September 23, June 22, December 22.
The tropics and polar circles divide the Earth's surface into belts that differ in solar illumination and the amount of heat received from the Sun. There are 5 zones of illumination: northern and southern polar, which receive little light and heat, a zone with a hot climate, and northern and southern belt, which receive more light and heat than polar ones, but less than tropical ones.
So, in conclusion, we can do general conclusion: uneven heating and illumination of the earth's surface are associated with the sphericity of our Earth and with the inclination of the earth's axis up to 66.5 ° to the orbit of rotation around the Sun.
The amount of solar energy reaching the surface of the Earth changes due to the movement of the earth around its axis and the Sun. These changes depend on the time of day and season. Usually at noon, the largest amount hits the Earth solar radiation than early in the morning or late in the evening. At noon, the Sun is at its zenith, and the length of the path of the Sun's rays through the Earth's atmosphere is reduced. As a result, less sunlight is refracted and reflected, hence more solar radiation reaches the earth's surface. The amount of energy falling per unit area per unit time depends on a number of factors: latitude, local climate, season of the year, the angle of inclination of the surface with respect to the Sun. The amount of solar energy reaching the Earth's surface differs from the average annual value: in winter - less than 0.8 kWh/m2 per day in Northern Europe and more than 4 kWh/m2 per day in summer time in the same region. The difference decreases as you get closer to the equator. The amount of solar energy also depends on the geographical location of the object: the closer to the equator, the greater it is. For example, the average annual total solar radiation incident on a horizontal surface is: in Central Europe, Central Asia and the Central region of Russia - approximately 1000 kWh / m 2; in the Mediterranean approximately 1500 kWh/m 2 ; in most desert regions of Africa, the Middle East and Australia - approximately 2200 kWh / m 2. Thus, the amount of solar radiation varies significantly depending on the time of year and geographical location. This factor plays essential role when calculating the efficiency of use of power plants that use solar panels and collectors. Fig.1.2 Distribution of solar radiation on the Earth's surface.
1.4 Development history of solar collectors
People have been heating water with the help of the Sun since ancient times, before fossil fuels took the lead in the world's energy. The principles of solar heating have been known for thousands of years. A black-painted surface heats up a lot in the sun, while light-colored surfaces heat up less, white surfaces less than all the others. This property is used in solar collectors - the most famous devices that directly use the energy of the sun. Collectors were developed about two hundred years ago. The most famous of them - The technology of manufacturing solar collectors reached an almost modern level in 1908, when William Bailey of the American "Carnegie Steel Company" invented a collector with a heat-insulated body and copper tubes. This collector was very similar to the modern thermosyphon system (see below). By the end of World War I, Bailey had sold 4,000 of these collectors, and the Florida businessman who bought the patent from him sold almost 60,000 collectors by 1941. Copper rationing introduced in the US during World War II led to a sharp decline in the market for solar heaters. Until the global oil crisis in 1973, these devices were neglected. However, the crisis has awakened a new interest in alternative energy sources. As a result, the demand for solar energy has also increased. Many countries are keenly interested in the development of this area. The efficiency of solar heating systems has steadily increased since the 1970s, thanks to the use of tempered glass with reduced iron content (it transmits more solar energy than ordinary glass) to cover the collectors, improved thermal insulation and a durable selective coating.
Solar energy is restored without human intervention naturally and is one of the environmentally friendly sources. Scientists around the world are working to develop systems that will expand the possibilities of using solar energy. One square meter The sun emits 62,900 kW of energy. This amount of radiation is equal to the work of 1 million electric lamps.(10)
Solar energy can be converted into usable energy and used for active and passive energy systems. Larger way to use sunlight this is the construction of buildings, the design of which took into account climatic conditions, selected building materials that make the most of solar energy, for heating or cooling, building lighting. With this design, the building structure itself is a collector that accumulates solar energy. Such buildings are environmentally friendly, comfortable and energy independent.
The principle of active systems is the use of solar energy, while a solar collector is used. It absorbs sunlight, turning it into heat, which heats buildings through the coolant, heats water and can convert it into electrical energy. Solar collectors can be used for household needs, agriculture and in industry.
Read also:
Reducing everything to abstraction and quantity |
1 polar belts
2 temperate zones
3 geographic zone
136 The lithosphere is the upper shell of the Earth and top partmantle.
The earth's crust beneath the continents is made up of
Sedimentary rocks
2 igneous
3 volcanic
4 metamorphic
granite
Basalt
The earth's crust is thicker
continents
2 oceans
3 lakes
4 plains
139The inner shells of the Earth include:
Core
2 lithosphere
3 platform
Mantle
5 earth's crust
Establish the sequence of arrangement of the Earth's shells in the order of their distance from the center.
3: asthenosphere
4: the earth's crust
141 Exogenous processes include:
Erosion
2 vulcanism
Aeolian processes
4 magmatism
5 earthquake
142 Endogenous processes include:
Tectonic movements
Volcanism
3 weathering
metamorphism
5 accumulation
6 aeolian processes
143Establish a correspondence between sources of external and internal forces Earth.
1: external forces
2: inner strength
A) the sun
B) the decay of radioactive elements of rocks
B) the earth's crust
D) weathering
144By origin, mountains are:
Tectonic
2 pleated
Volcanic
Erosive
6 young
145 Plains are:
lowlands
uplands
4 depressions
Plateau
146Plains of mainland Eurasia:
West Siberian
2 La Platskaya
Caspian
4Amazonian
5 Central North American
Specify how to determine absolute altitude places on the map
1 depth scale
Height scale
3 scale
4 degree grid
The composition of the hydrosphere includes:
Waters of the World Ocean
Land waters
The groundwater
4water in living organisms
5water in the bowels of the Earth
6atmospheric water
Sequence the oceans in descending order of their maximum depth.
2: Atlantic
3: Indian
4: Arctic
150. The property of water, which ensures its circulation in nature:
1 fluidity
2 solvent
3 heat capacity
Free transition from one physical state to another
151 The inland sea is:
1 Beringovo
2 Karskoe
Black
4 Barents
152 Continental shoal or shelf is a shallow part that borders the mainland with depth:
0 to 200 m
2 0 to 2500 m
3 0 to 1000 m
4 0 to 6000 m
153 The temperature of surface waters in the ocean decreases from:
Equator to the poles
2poles to equator
3 prime meridian west
4Greenland to the equator
154 Stock fresh water on earth is:
Read in the same book: Geographic longitude is measured from ...
| Any point on mainland Australia has … | Spirals | Geysers | The main property of the biosphere | Oakwood | Selects the forms and methods of development and education of schoolchildren by means of natural science | mybiblioteka.su - 2015-2018.
angles of incidence of the sun
The height of the sun significantly affects the flow of solar radiation. When the angle of incidence of the sun's rays is small, the rays must pass through the thickness of the atmosphere.
Solar radiation is partially absorbed, part of the rays are reflected from particles suspended in the air and reach the earth's surface in the form of scattered radiation.
The height of the sun changes continuously as it passes from winter to summer, as it does with the change of day.
The angle of incidence of the sun's rays reaches its greatest value at 12:00 pm ( solar time). It is customary to say that at this moment in time the sun is at its zenith. At noon, the radiation intensity also reaches maximum value. The minimum values of the radiation intensity are reached in the morning and in the evening, when the sun is low above the horizon, also in winter. True, in winter a little more direct sunlight falls on the earth.
This is because absolute humidity winter air is lower “and therefore it absorbs less solar radiation.
On fig. 37 shows how high the radiation intensity reaches on a perpendicular surface oriented towards the sun, despite the fact that the acute angle of incidence of the sun's rays varies.
The initial part of this curve quite accurately reflects the position on a clear March day. The sun rises at 6:00 in the east and slightly illuminates the eastern facade wall (only in the form of radiation reflected by the atmosphere).
Topic: Distribution of sunlight heat on earth
With an increase in the angle of incidence of sunlight, the intensity of solar radiation falling on the surface of the facade wall rapidly increases.
At about 8 a.m., the intensity of solar radiation is already about 500 W/m2, and it reaches its maximum value of about 700 W/m2 on the southern front wall of the building a little earlier than noon.
Enlarge image
When the earth rotates around its axis in one day, i.e.
That is, with the apparent movement of the sun around the globe, the angle of incidence of the sun's rays changes not only in the vertical, but also in the horizontal direction. This angle in the horizontal plane is called the azimuth angle. It shows how many degrees the angle of incidence of the sun's rays deviates from the north direction, if a full circle is 360 °.
The vertical and horizontal angles are interconnected so that when the seasons change, always twice a year, the angle of the height of the sun in the sky turns out to be the same for the same values of the azimuth angle.
On fig. 39 shows the trajectories of the sun during its apparent movement around the globe in winter and summer on the days of the spring and autumn equinoxes.
By projecting these trajectories on a horizontal plane, a planar image is obtained, with which it is possible to accurately describe the position of the sun on the globe. Such a map of the solar trajectory is called a solar diagram or simply a solar map. Since the trajectory of the sun changes when moving from the south (from the equator) to the north, each latitude has its own characteristic solar map.
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DISTRIBUTION OF HEAT AND LIGHT ON THE EARTH
The Sun is the star of the solar system, which is the source of a huge amount of heat and blinding light for the planet Earth. Despite the fact that the Sun is at a considerable distance from us and only a small part of its radiation reaches us, this is quite enough for the development of life on Earth. Our planet revolves around the sun in an orbit.
If the Earth is observed from a spacecraft during the year, then one can notice that the Sun always illuminates only one half of the Earth, therefore, there will be day there, and at that time there will be night on the opposite half. The earth's surface receives heat only during the day.
Our Earth is heating unevenly.
Distribution of sunlight and heat on Earth, thermal zones, seasons
The uneven heating of the Earth is explained by its spherical shape, so the angle of incidence of the sun's ray in different areas is different, which means that different parts of the Earth receive different amounts of heat.
At the equator, the sun's rays fall vertically, and they strongly heat the Earth. The farther from the equator, the angle of incidence of the beam becomes smaller, and consequently, these territories receive less heat. The same power beam of solar radiation heats a much smaller area near the equator, since it falls vertically. In addition, rays falling at a smaller angle than at the equator - penetrating the atmosphere, travel a longer path in it, as a result of which part of the sun's rays are scattered in the troposphere and do not reach the earth's surface.
All this indicates that as you move away from the equator to the north or south, the air temperature decreases, as the angle of incidence of the sun's beam decreases.
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How many different lighting? 5 Pillar Dog Belt…
how many different lighting?
- 5 pol
- Belts Belts of lighting illumination are the surfaces of parts of the Earth bounded by the tropics, polar circles and various lighting conditions.
It is located between the tropics in the tropics, where twice a year (and once a year in the tropics) you can see the midday sun at its zenith. From the Arctic Circle to the Pole in each hemisphere there is a polar belt, here there is a polar day and a polar night.
Distribution of sunlight and heat on Earth
In temperate regions located in the northern and southern hemispheres during the tropical and polar circles, the sun does not meet at its zenith, the polar day and polar night are not observed.
Tj emit lighting zone 5: -north and south polarity, receiving only a little light and heat. Tropical zone with hot climates - incorrect and southern temperate zones, which receive light and more heat than polar ones, but are less tropical.
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§ 30. Distribution of sunlight and heat on Earth (textbook)
§ 30. Distribution of sunlight and heat on Earth
1. Remember why on Earth there is a change of day and night and seasons.
2. What is called the Earth's orbit?
The change in the height of the sun above the horizon during the year. To understand why throughout the year the Sun at noon is at different heights above the horizon, remember from the lessons of natural history the features of the movement of the Earth around the Sun.
The globe shows that the earth's axis is tilted.
During the motion of the Earth around the Sun, the angle of inclination does not change. Due to this, the Earth returns to the Sun with more than the Northern, then the Southern hemisphere. This changes the angle of incidence of the sun's rays by earth's surface. And, accordingly, one or the other hemisphere is more illuminated and heated.
If the Earth's axis were not tilted, perpendicular to the plane of the Earth's orbit, then the number solar heat on each parallel during the year, would not change.
Then, in your observations of the height of the midday Sun, you would record the same length of the gnomon's shadow for a whole year. This would indicate that during the year the length of the day is always equal to the night.
Then the earth's surface was heated during the year in the same way and the weather would not exist.
Illumination and heating of the Earth's surface during the year. On the surface of the spherical Earth, solar heat and light are distributed unevenly.
This is due to the fact that the angle of incidence of rays at different latitudes is different.
You already know that the earth's axis is inclined to the plane of the orbit at an angle. With its northern end, it is directed towards the North Star. The sun always illuminates half of the Earth.
At the same time, the Northern Hemisphere is more illuminated (and the day there lasts longer than in the other hemisphere), then, on the contrary, the Southern Hemisphere. Twice a year, both hemispheres are illuminated equally (then the length of the day in both hemispheres is the same).
When the Earth is facing the Sun with the North Pole, then it illuminates and heats more North hemisphere.
The days are getting longer than the night.The warm season is coming - summer.
Distribution of heat and light on Earth
At the pole and in the circumpolar part, the Sun shines around the clock and does not set below the horizon (Night does not come). This phenomenon is called polar day. At the Pole, it lasts 180 days (half a year), but the farther south, the shorter its duration decreases by a day at the parallel of 66.50 bn. sh. This parallel is called Arctic Circle.
South of this line, the Sun descends below the horizon and the change of day and night occurs in the usual order for us - every day. June 22 - Solar rays will fall vertically (at the largest angle - 900) Parallel 23.5 Mon. sh. This day will be the longest and the night the shortest of the year. This parallel is called Northern tropic, And the day of June 22 - summer solstice.
Currently South Pole ion abstracted from the Sun illuminates and heats the southern hemisphere less.
It's winter there. During the day, the sun's rays do not fall at all on the pole and the circumpolar part. The sun does not rise from the horizon and the day does not come. This phenomenon is called polar night. At the pole itself, it lasts 180 days, and the farther north, the shorter it becomes to one day at the parallel of 66.50 S. sh. This parallel is called South polar circle. To the north of it, the Sun appears on the horizon and the change of day and night occurs every day.
Three months later, on September 23, the Earth will take such a position relative to the Sun, when the sun's rays equally illuminate both the Northern and Southern hemispheres.
The sun's rays fall vertically at the equator. On the whole Earth, except for the poles, day is equal to night (12 hours each). This day is called day of the autumnal equinox.
Three months later, on December 22, the Southern Hemisphere will return to the Sun. There will be summer. This day will be the longest and the night the shortest.
A polar day will come in the polar region. The rays of the Sun fall vertically on the parallel of 23.50 S. sh. On the other hand, it will be winter in the Northern Hemisphere. This day will be the shortest, and the night will be long. Parallel 23.50 S sh. is called Southerntropic, and the day is December 22 - winter solstice.
Three months later, on March 21, both hemispheres will again be illuminated equally, the day will be equal to the night.
The rays of the sun fall vertically on the equator. This day is called spring equinox.
In Ukraine highest altitude Sun at noon - 61-690 (June 22), the smallest -14-220 (December 22).
Entertaining geography
words’ Slavic GodSun
The ancient Slavs called the god of light and the sun Dazhbog.
In the famous literary work"The Tale of Igor's Campaign" of our ancestors, the Russians, is called the grandchildren of Dazhdbog. Along with other gods set by Prince Vladimir in Kiev, Dazhbog also stood. According to ancient myths, he is accompanied in the sky by three solar brothers: Yarilo- God spring equinox, Semiarilo- God of the summer solstice Kolyada— God of the Winter Solstice.
The day of the birth of the young Sun was considered the day of the winter solstice. God was considered the guardian of this luminous trinity. Trojan- Lord of heaven, earth and the otherworldly kingdom.
Rice.
Annual motion of the Earth around the Sun
Thermal belts of the Earth. Uneven heating of the earth's surface causes different temperatures air at different latitudes. Latitudinal bands with certain air temperatures are called thermal belts. The belts differ from each other in the amount of heat coming from the Sun. Their stretching depending on the temperature distribution is well illustrated isotherms(From the Greek "iso" - the same, "terma" - heat).
These are lines on a map that connect points of the same temperature.
hot belt located along the equator, between the northern and southern tropics. It is limited on both sides of the 20 0С isotherms. It is interesting that the boundaries of the belt coincide with the boundaries of the distribution of palms on land and corals in the ocean.
Here the earth's surface receives the greatest solar heat. Twice a year (December 22 and June 22) noon the sun's rays fall almost vertically (at an angle of 900). The air from the surface gets very hot.
Therefore, it is hot there during the year.
temperate zones(In both hemispheres) are adjacent to the hot belt. They stretched in both hemispheres between the Arctic Circle and the tropic. The sun's rays fall on the earth's surface with a certain inclination. Moreover, the further north, the dark slope is greater.
Therefore, the sun's rays heat the surface less. As a result, the air heats up less. That's why in temperate zones colder than hot. The sun is never at its zenith there. Clearly defined seasons: winter, spring, summer, autumn.
Moreover, the closer to the Arctic Circle, the longer and colder the winter. The closer to the tropic, the longer and warmer the summer. Temperate belts from the side of the poles are limited by an isotherm warm month 10 0С. It is the limit of the distribution of forests.
cold belts(Northern and southern) of both hemispheres lie between the isotherms of 10 0C and 0 0C of the warmest month. The sun there in winter does not appear above the horizon for several months.
And in summer, although it does not go beyond the horizon for months, it is very low above the horizon. Its rays only glide over the surface of the Earth and heat it weakly. The Earth's surface not only heats but also cools the air. Therefore, the temperatures there are low. Winters are cold and harsh, while summers are short and cool.
Two belt of eternal cold(northern and southern) are contoured by an isotherm with temperatures of all months below 0 0С. This is the realm of eternal snigs and ice.
So, the heating and lighting of each locality depends on the position in the thermal zone, that is, on the geographical latitude.
The closer to the equator, the greater the angle of incidence of the sun's rays, the stronger the surface heats up and the air temperature rises. Conversely, with the distance from the equator to the poles, the angle of incidence of the rays decreases, respectively, the air temperature decreases.
It is important to remember that the lines of the tropics and polar circles outside the thermal zones are taken conditionally. Since in reality the air temperature is also determined by a number of other conditions.
Rice.
Thermal belts of the Earth
Questions and tasks
1. Why does the height of the Sun change during the year?
2. Which hemisphere will the Earth face the Sun when in Ukraine: a) in the north on June 22; b) noon on December 22?
3.Where will the average annual air temperature be higher: in Singapore or Paris?
4. Why average annual temperatures decrease from the equator to the poles?
5. In what thermal zones are the continents Africa, Australia, Antarctica, North America, Eurasia?
6. In what thermal zone is the territory of Ukraine?
7.Find a city on the map of the hemispheres, if it is known that it is located at 430x.
The intensity of sunlight that reaches the earth varies with time of day, year, location, and weather conditions. The total amount of energy calculated per day or per year is called irradiation (or in another way "the arrival of solar radiation") and shows how powerful the solar radiation was. Irradiation is measured in W*h/m² per day or other period.
The intensity of solar radiation in free space at a distance equal to the average distance between the Earth and the Sun is called the solar constant. Its value is 1353 W / m². When passing through the atmosphere, sunlight is attenuated mainly due to absorption of infrared radiation by water vapor, ultraviolet radiation by ozone, and scattering of radiation by atmospheric dust particles and aerosols. Indicator atmospheric influence on the intensity of solar radiation reaching the earth's surface is called "air mass" (AM). AM is defined as the secant of the angle between the Sun and the zenith.
Figure 1 shows the spectral distribution of solar radiation intensity in various conditions. The upper curve (AM0) corresponds to the solar spectrum beyond earth's atmosphere(for example, on board a spacecraft), i.e. at zero air mass. It is approximated by the intensity distribution of black body radiation at a temperature of 5800 K. Curves AM1 and AM2 illustrate the spectral distribution of solar radiation on the Earth's surface when the Sun is at the zenith and at an angle between the Sun and the zenith of 60°, respectively. In this case, the total radiation power is about 925 and 691 W / m², respectively. The average intensity of radiation on Earth approximately coincides with the intensity of radiation at AM=1.5 (the Sun is at an angle of 45° to the horizon).
Near the surface of the Earth, one can take the average value of the intensity of solar radiation as 635 W / m². On a very clear sunny day, this value ranges from 950 W/m² to 1220 W/m². The average value is approximately 1000 W / m². Example: Total radiation intensity in Zurich (47°30′ N, 400 m above sea level) on a surface perpendicular to the radiation: 1 May 12:00 1080 W/m²; 21 December 12:00 930 W/m² .
To simplify the calculation of solar energy, it is usually expressed in hours of sunshine with an intensity of 1000 W/m². Those. 1 hour corresponds to the arrival of solar radiation of 1000 W*h/m². This roughly corresponds to the period when the sun shines in summer in the middle of a sunny cloudless day on a surface perpendicular to the sun's rays.
Example
The bright sun shines with an intensity of 1000 W / m² on a surface perpendicular to the sun's rays. For 1 hour, 1 kWh of energy falls on 1 m² (energy is equal to the product of power and time). Similarly, an average solar input of 5 kWh/m² per day corresponds to 5 peak hours of sunshine per day. Do not confuse peak hours with actual duration daylight hours. During the daylight hours, the sun shines with different intensity, but in total it gives the same amount of energy as if it shone for 5 hours at maximum intensity. It is the peak hours of sunshine that are used in the calculations of solar power plants.
The arrival of solar radiation varies during the day and from place to place, especially in mountainous areas. Irradiation varies on average from 1000 kWh/m² per year for northern European countries, to 2000-2500 kWh/m² per year for deserts. Weather and the declination of the sun (which depends on the latitude of the area), also leads to differences in the arrival of solar radiation.
In Russia, contrary to popular belief, there are a lot of places where it is profitable to convert solar energy into electricity using. Below is a map of solar energy resources in Russia. As you can see, in most of Russia it can be successfully used in seasonal mode, and in areas with more than 2000 hours of sunshine per year - all year round. Naturally, in winter, energy production solar panels significantly reduced, but still the cost of electricity from a solar power plant remains significantly lower than from a diesel or gasoline generator.
It is especially beneficial to use where there are no centralized electrical networks and energy supply is provided by diesel generators. And there are a lot of such regions in Russia.
Moreover, even where there are grids, the use of solar panels operating in parallel with the grid can significantly reduce energy costs. Given the current trend towards higher tariffs for Russia's natural energy monopolies, installations solar panels becomes a smart investment.
On the surface of the spherical Earth, solar heat and light are distributed unevenly. This is due to the fact that the angle of incidence of rays at different latitudes is different.
You already know that the earth's axis is inclined to the plane of the orbit at an angle. Its northern end is directed towards the North Star. The sun always illuminates half of the Earth. At the same time, the Northern Hemisphere is more illuminated (and the day there lasts longer than in the other hemisphere), then, on the contrary, the Southern Hemisphere. Twice a year, both hemispheres are equally illuminated (then the length of the day in both hemispheres is the same).
When the Earth is facing the Sun with the North Pole, then it illuminates and heats the Northern Hemisphere more. The days are getting longer than the nights. The warm season is coming - summer. At the pole and in the circumpolar part, the Sun shines around the clock and does not set below the horizon (Night does not come). This phenomenon is called polar day. At the Pole, it lasts 180 days (half a year), but the farther south, the shorter its duration is to a day at the parallel of 66.5 0 Mon. sh. This parallel is called the Arctic Circle. To the south of this line, the Sun descends below the horizon and the change of day and night occurs in the usual order for us - every day. June 22 - The sun's rays will fall vertically (at the largest angle - 90 0) On the parallel 23.5 mon. sh. This day will be the longest and the shortest night of the year. This parallel is called the Northern Tropic, And the day of June 22 is the summer solstice.
Currently, the South Pole is distracted from the Sun and it illuminates and heats the Southern Hemisphere less. It's winter there. During the day, the sun's rays do not fall at all on the pole and the circumpolar part. The sun does not rise from the horizon and the day does not come. This phenomenon is called polar night. At the Pole itself, it lasts 180 days, and the farther north, the shorter it becomes to one day at the parallel of 66.5 0 S. sh. This parallel is called the Antarctic Circle. To the north of it, the Sun appears on the horizon and the change of day and night occurs every day. June 22 The day will be the shortest of the year. For the Southern Hemisphere, it will be the winter solstice.
Three months later, on September 23, the Earth will take such a position relative to the Sun, when the sun's rays equally illuminate both the Northern and Southern hemispheres. The sun's rays fall vertically at the equator. On the whole Earth, except for the poles, day is equal to night (12 hours each). This day is called the autumnal equinox.
In three more months, on December 22, it will return to the Sun southern hemisphere. There will be summer. This day will be the longest and the night the shortest. In the polar region, a polar day will come. The rays of the Sun fall vertically on the parallel 23.5 0 S. sh. But it will be winter in the Northern Hemisphere. This day will be the shortest and the night the longest. Parallel 23.5 0 S sh. is called the Southern Tropic, and December 22 is the winter solstice.
Three months later, on March 21, both hemispheres will again be equally illuminated, the day will be equal to the night. The rays of the sun fall vertically on the equator. This day is called the spring equinox.
In Ukraine, the highest height of the Sun at noon is 61-69 0 (June 22), the lowest - 14-22 0 (December 22).
The sun is the main source of heat and light on Earth. This huge ball of gas with a surface temperature of about 6000 ° C radiates a large amount of energy, which is called solar radiation. It heats our Earth, sets the air in motion, forms the water cycle, creates conditions for the life of plants and animals.
Passing through the atmosphere, part of the solar radiation is absorbed, part is scattered and reflected. Therefore, the flow of solar radiation, coming to the surface of the Earth, gradually weakens.
Solar radiation arrives at the Earth's surface directly and diffusely. Direct radiation represents the flow parallel rays coming directly from the solar disk. Scattered radiation comes from all over the sky. It is believed that the heat input from the Sun per 1 hectare of the Earth is equivalent to burning almost 143 thousand tons of coal.
The sun's rays, passing through the atmosphere, heat it up a little. The heating of the atmosphere comes from the surface of the Earth, which, absorbing solar energy, turns it into heat. Air particles, in contact with a heated surface, receive heat and carry it away into the atmosphere. This heats up the lower layers of the atmosphere. Obviously, the more the Earth's surface receives solar radiation, the more it heats up, the more the air heats up from it.
Air temperature is measured with thermometers (mercury and alcohol). Alcohol thermometers are used when the air temperature is below -38 ° C. On meteorological stations thermometers are placed in a special booth, built from separate plates (blinds) located at a certain angle, between which air circulates freely. Direct sunlight does not fall on thermometers, so air temperature is measured in the shade. The booth itself is located at a height of 2 m from the earth's surface.
Numerous observations of air temperature showed that the highest temperature was observed in Tripoli (Africa) (+ 58°С), the lowest - at Vostok station in Antarctica (-87.4°С).
The influx of solar heat and the distribution of air temperature depends on the latitude of the place. Tropical area receives more heat from the Sun than the temperate and polar latitudes. The most heat is received by the equatorial regions of the Sun - the star of the solar system, which is the source of a huge amount of heat and blinding light for the planet Earth. Despite the fact that the Sun is at a considerable distance from us and only a small part of its radiation reaches us, this is quite enough for the development of life on Earth. Our planet revolves around the sun in an orbit. If the Earth is observed from a spacecraft during the year, then one can notice that the Sun always illuminates only one half of the Earth, therefore, there will be day there, and at that time there will be night on the opposite half. The earth's surface receives heat only during the day.
Our Earth is heating unevenly. The uneven heating of the Earth is explained by its spherical shape, so the angle of incidence of the sun's ray in different areas is different, which means that different parts of the Earth receive different amounts of heat. At the equator, the sun's rays fall vertically, and they strongly heat the Earth. The farther from the equator, the angle of incidence of the beam becomes smaller, and consequently, these territories receive less heat. The same power beam of solar radiation heats a much smaller area near the equator, since it falls vertically. In addition, rays falling at a smaller angle than at the equator - penetrating the atmosphere, travel a longer path in it, as a result of which part of the sun's rays are scattered in the troposphere and do not reach the earth's surface. All this indicates that as you move away from the equator to the north or south, the air temperature decreases, as the angle of incidence of the sun's beam decreases.
The distribution of precipitation on the globe depends on how many clouds containing moisture form over a given area or how many of them the wind can bring. Air temperature is very important, because intensive evaporation of moisture occurs precisely at high temperature. Moisture evaporates, rises up and clouds form at a certain height.
The air temperature decreases from the equator to the poles, therefore, the amount of precipitation is maximum in equatorial latitudes and decreases towards the poles. However, on land, the distribution of precipitation depends on a number of additional factors.
There is a lot of precipitation over coastal areas, and as you move away from the oceans, their amount decreases. More precipitation on the windward slopes of mountain ranges and much less on the leeward slopes. For example, on Atlantic coast Norway in Bergen receives 1730 mm of precipitation per year, and in Oslo (behind the ridge - approx. from site), it receives an average of more than 11,000 mm of precipitation per year. Such an abundance of moisture is brought to these places by the humid summer southwest monsoon, which rises along the steep slopes of the mountains, cools and pours with powerful rain.
The oceans, whose water temperature changes much more slowly than the temperature of the earth's surface or air, have a strong moderating effect on the climate. At night and in winter, the air over the oceans cools much more slowly than over land, and if oceanic air masses move over the continents, this leads to warming. Conversely, during the day and summer, the sea breeze cools the land.
The distribution of moisture on the earth's surface is determined by the water cycle in nature. Every second into the atmosphere, mainly from ocean surfaces, evaporates great amount water. Humid oceanic air, rushing over the continents, cools. The moisture then condenses and returns to the earth's surface in the form of rain or snow. It is partly preserved in snow cover, rivers and lakes, and partly returns to the ocean, where evaporation occurs again. This completes the hydrological cycle.
The distribution of precipitation is also influenced by the currents of the oceans. Over areas near which pass warm currents, the amount of precipitation increases, as the air heats up from warm water masses, it rises and clouds with sufficient water content form. Over the territories near which cold currents pass, the air cools, sinks, clouds do not form, and precipitation is much less.
Since water plays a significant role in erosion processes, it thereby affects the movement earth's crust. And any redistribution of masses due to such movements in the conditions of the Earth rotating around its axis can, in turn, contribute to a change in the position of the earth's axis. During ice ages, sea levels drop as water accumulates in glaciers. This, in turn, leads to the growth of continents and an increase in climatic contrasts. Reducing river runoff and lowering the level of the World Ocean hinder the achievement of warm ocean currents cold regions, leading to further climate change.
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