Earth's atmosphere

Earth's atmosphere is a layer of a mixture of gases surrounding the ball to the floor Mjdhubh by gravity. It has 78 % of the nitrogen and 21 % oxygen, argon , carbon dioxide , water vapor , hydrogen, helium , neon and xenon. The atmosphere protects the Earth from ultraviolet absorption and works on milder temperatures on the planet's surface.

The atmosphere is an extensive reservoir of water is used to move the water around the Earth, as the volume of water in the atmosphere to about 12,900 cubic kilometers falls mostly as rain in the oceans and seas as if the event and fell all the water in the atmosphere at the same time as rain , it will cover the planet to a depth of 2.5 cm. The estimated weight of the clouds, which contained thousands of billions of tons

Be air
Air contains a mixture of gases, extends from the surface of the Earth to outer space. Gravity works on installing the atmosphere around the earth. And gases move freely among them. Reflects sunlight, which consists of a mixture of all the colors, the atmosphere will operate on air molecules dispersed in all directions. The sky looks blue, because blue light more dispersed than other colors.

Air gases
Nitrogen and oxygen from the gas main in the air. It has the air of other gases such as water vapor and carbon dioxide, neon, argon , helium, krypton and xenon , hydrogen and ozone. The water vapor in the air is water in the form of an invisible gas. Nitrogen constitutes 78% of the dry air ( free from water vapor ), oxygen constitutes 21% of the dry air. It contains the rest (1%), mainly , on the other argon and other gases. Some of the gases in the atmosphere is very important. When we breathe, we take oxygen from the air and get out carbon dioxide. Green plants take carbon dioxide and release oxygen in the process of the food industry or the so-called process of photosynthesis. The lead role of oxygen in the air in some chemical processes Ksdo iron and manufacture of cider vinegar. Most types of oxygen in order to burn the fuel. And some of the types of bacteria in the soil to convert nitrogen in the air into fertilizer chemical plant. And helps carbon dioxide and water vapor on the survival of the earth warm, where forbid the part of the Earth's surface temperature , which gained from the sun's rays from leaking into outer space. This behavior is defined by the impact of greenhouse gases. And required the presence of water vapor in the atmosphere to form rain and snow. And ozone form of oxygen, absorbs a large part of the solar UV invisible harmful. Air humidity. It is in the form of water vapor atoms. And enters the steam into the atmosphere when the water evaporates from the oceans, lakes and rivers , and moist soil and plants. With the high amount of water vapor in the air increases humidity, which depends on the temperature and on the location of the place. The air in contact with the water bodies of rising humidity, while the fall in the desert, and the air is dry. The warm air can carry the amount of steam more than cold air. Therefore, humidity varies with different weather, so the air is less moisture in the days to net him on cloudy days. And when it cools the air to a sufficient degree, the steam turns to droplets of water or ice crystals. This process is called condensation. Called the temperature at which water vapor begins then condensation dew point. And when it appears on the surface of the water granules cup cold water, the air is in contact with the glass has cooled to a lesser degree than the dew point. When the dew point, relative humidity of 100%. The relative humidity is the amount of water vapor in the air true at a given temperature, relative to the amount of water vapor that can be carried by the air when the degree of saturation at the same temperature. When the relative humidity up to 100%, the air has reached the maximum afford to water vapor. In some cases it may rain without the relative humidity up to 100% near the Earth's surface, but may increase it in the clouds. The higher the temperature of the air I said. Therefore, the clouds formed when a huge mass of cool moist air to rise due to the higher, the temperature drops below the dew point. The clouds contain the air is filled with huge quantities of water droplets or ice crystals. And it rains or when the ice becomes water droplets or ice crystals fall of gravity so that the clouds outside. Fog and pull close to the earth's surface. Particles in the air. Air contains many of the solid particles and micro- labeled aerosol. Qatar and mostly up to 0.1 micrometers. So they are not visible, but when clustered in huge quantities. The many aerosol particles into the air of active volcanoes, and car exhaust , forest fires and smoke factories. Raise as wind, sand and dust particles from the surface of the earth into the air. And also includes aerosol particles suspended in the air pollen trees and sea salts and meteoritic particles and micro- organisms called microbes. With the passage of time, continue to add aerosol particles into the atmosphere, but they do not stay stuck in the air forever. It holds the rain and ice removed from the air, where it becomes fresh air after the rain and snow. The other part of the aerosol Cuomo gradually on the surface of the earth. Vary the amount of aerosol particles in the air near the ground from one place to another, since it has a cubic meter of air over the ocean on the particle billion , while featuring cubic meter of air over major cities around 100 billion particle. Due to the lack of aerosols in the upper atmosphere, the air is usually more purity.

Layers of the atmosphere
The atmosphere is composed of six main layers overlap in each chapter, making them almost impossible these classes :

Almtkor rotor ( the troposphere ), a class that occurs most atmospheric changes that are evident daily and less than the temperatures rise with the layer that contains most of the water vapor, oxygen and carbon dioxide concentrations of human activities.

Stratosphere, a layer above the troposphere extends from the high 21 to 80 kilo meters above the ground. This phase is characterized by fluctuations shown to be free of cost or storms. And there are belt known as the ozone layer that protects Earth's surface from the dangers of UV radiation.

Almtkor East is this layer beyond the parties to the upper layer Alatratosevar, characterized this layer rising air temperature in the divided lower then decline gradually rise to the top ends of the upper class , and thanks to this aerobics class in the occurrence of burning meteors and meteorites falling and flying to the surface of the ball earth '

Almtkor warming (English Thermosphere Layer) is a thermal Almtkor fourth layer of the atmosphere. Almtkor warming rises above sea level to an altitude of 500 km, when the sun is active , and between 750 km , when the sun is quiet. Thus, thickness ranges above the limit Mazoboz between 420-670 km, respectively. There is no class between them and the air followed by a thermal limit, and therefore determine a peak Thermopoz on the basis of the gaseous composition. Prove the temperature at -93 C temperature for several kilometers on the bottom and then gradually increasing with the rise which, as of approximately 700 C at 300 km altitude , but it has approximately 1700 C when the sun is still active and the temperature on the set until the end of Almtkor during the thermal layer , followed by air. It seems clear that the name may derive from the word (Thermo) Greek, which means warm to denote the severity of the heat.

Almtkor an ionized layer above the stratosphere from 80 kilometers high and 360 kilometers or even more, and that layer is characterized by lightly Ghazadtha and dominated by hydrogen and helium.

Xzausver form a layer exosphere last class of the external atmosphere, has derived its name from the word "Exo" which means outside. Exosphere layer extends high above the layer Tyrmosver until the end of the atmosphere at an altitude of around 64400 km. The air molecules become scarce in the exosphere layer to the extent that it is non-existent, for example , at the bottom of the can off gas atom about 10 km before crashing into other gaseous seed. Usually scientists know the distance traveled by gaseous atoms before they collide with another atom of free passage.

Mtkor the East or the mesosphere is the third or layers of the atmosphere after the troposphere ( Almtkor rotor ) and the stratosphere, and a height of about 50 to 80 kilometers above sea level. In spite of the rise of this layer from the surface of the sea, but it is characterized by high temperature due to the presence of the layer of ozone in the lower part of this layer (o3) which has a thickness of about 30 km and you are blocking UV rays that come from solar radiation , in addition to the most meteorites and meteors burn up in this layer , which leads to a rise in the temperature of this layer. Spanning the great help of the atmosphere in the space to the combustion of millions of meteors

Air humidity
It is in the form of water vapor atoms. And enters the steam into the atmosphere when the water evaporates from the oceans, lakes and rivers , and moist soil and plants. With the high amount of water vapor in the air increases humidity, which depends on the temperature and on the location of the place. The air in contact with the water bodies of rising humidity, while the fall in the desert, and the air is dry. The warm air can carry the amount of steam more than cold air. Therefore, humidity varies with different weather, so the air is less moisture in the days to net him on cloudy days. And when it cools the air to a sufficient degree, the steam turns to droplets of water or ice crystals. This process is called condensation. Called the temperature at which water vapor begins then condensation dew point. And when it appears on the surface of the water granules cup cold water, the air is in contact with the glass has cooled to a lesser degree than the dew point. When the dew point, relative humidity of 100%. The relative humidity is the amount of water vapor in the air true at a given temperature, relative to the amount of water vapor that can be carried by the air when the degree of saturation at the same temperature. When the relative humidity up to 100%, the air has reached the maximum afford to water vapor. In some cases it may rain without the relative humidity up to 100% near the Earth's surface, but may increase it in the clouds. The higher the temperature of the air I said. Therefore, the clouds formed when a huge mass of cool moist air to rise due to the higher, the temperature drops below the dew point. The clouds contain the air is filled with huge quantities of water droplets or ice crystals. And it rains or when the ice becomes water droplets or ice crystals fall of gravity so that the clouds outside. Fog and pull close to the earth's surface.

Particles in the air
Air contains many of the solid particles and micro- labeled aerosol. Qatar and mostly up to 0.1 micrometers. So they are not visible, but when clustered in huge quantities. The many aerosol particles into the air of active volcanoes, and car exhaust , forest fires and smoke factories. Raise as wind, sand and dust particles from the surface of the earth into the air. And also includes aerosol particles suspended in the air pollen trees and sea salts and meteoritic particles and micro- organisms called microbes. With the passage of time, continue to add aerosol particles into the atmosphere, but they do not stay stuck in the air forever. It holds the rain and ice removed from the air, where it becomes fresh air after the rain and snow. The other part of the aerosol Cuomo gradually on the surface of the earth. Vary the amount of aerosol particles in the air near the ground from one place to another, since it has a cubic meter of air over the ocean on the particle billion , while featuring cubic meter of air over major cities around 100 billion particle. Due to the lack of aerosols in the upper atmosphere, the air is usually more purity.

Weight and pressure
We can not usually feeling the weight of the air, because the air is less than the weight of solids and liquid much. But you can be sure that the weight of the air through a simple experiment. First, unload the air from the bottle -mediated pump suction. Then close the bottle and Nzinha. Second, a lid, the air enters into the bottle. When you weigh the bottle again, the weight is greater , so the extra weight is the weight of the air. Air consists mainly of nitrogen and oxygen. It constituted 99% of the air that was removed from moisture. The rest of the argon and other gases only 1%. Weighs cubic meter of air at sea about 1170 gm, while weighing up the atmosphere around the globe about 5,200,000,000,000,000 metric tons. The weight of the air from the top of the atmosphere through the layers of the atmosphere to the Earth's surface air pressure or what is familiar to atmospheric pressure. The atmospheric pressure at sea level at an average of about 1,033 kg / cm ² (101,3 kPa ). The air pressure on our shoulders the weight of up to 0.9 metric tons. We do not feel this pressure because there is a pressure equal to the inside of our bodies and in all directions. Measured atmospheric pressure device called a barometer. And expresses the mercurial barometer for air pressure in millimeters of mercury, or a unit of measurement called a bar or millibars. The bar is a unit of atmospheric pressure in the metric system. And Milibar equivalent of 0,001 bar. The average atmospheric pressure at sea level 760 mm Hg or 1,013 millibars. Usually have lower air pressure in the windy days and humid days than in the days of the net and dry days. So indicates low air pressure on the approaching storm. In the upper atmosphere, the air pressure is less than the air pressure near the Earth's surface, due to the decreased air pressure from the bottom to the top. When you ascend to the high-rise building elevator mediated fast, you can feel the air pressure change , with less air pressure inside the elevator with the rise, while keeping the air pressure inside the ear as it is. This difference in pressure makes the eardrum hurtling outward quietly until he finds a way out some air out of the ear. The use atmospheric pressure as a force in many ways. When Nschwt drink through a pipette, for example , we do not really pull the liquid up through the absorbent, but we are pumping air them , it becomes a pressure within less pressure on the fluid outside the absorbent, thereby acting pressure above the liquid to push the liquid from the cup to the top through absorbents to the mouth. In the same way working pumps sucking vacuum cleaners.

Air movement
Air moves on the surface of the earth in the form of winds. The sun's heat and cause the movement of the wind due to the lack of the Earth's surface is heated evenly. The air above the warm areas actually expands and becomes lighter. Here, air rises as establishing an area of ​​low pressure near the Earth's surface. Arise when the wind moves the air cooler and heavier toward areas of low pressure to replace the air rising to the top. Often arise at wind along the shores of one of the ocean during the day, because the land heats faster than water. The air above the beach becomes warmer than the air above the water, warm air rises to the top and be replaced by cooler air coming from inside the ocean , forming what is known as the sea breeze. At night, the air above the beach becomes colder than the air in contact to the ocean. Here are reflected in the direction of the wind, the breeze Come out towards the sea and the land is a land breeze. Warm air rises over the equator constantly. Vthb cold winds from the north and south permanently to replace the rising air. The result is the movement of air from the wind this Ntacan called trade winds. This wind is not blowing toward the equator straight lines due to the Earth's rotation around itself, as they tend trade winds north of the equator to the right of the original direction , that is, they are moving towards the south-west. The trade winds south of the equator, they veer to the left of the original direction , and moving toward the north-west. The effect is called the Earth's rotation on the direction of the wind force or effect Alcreolasah Alcreolasa ( Alcreolasa effect ). Also affect power Alcreolasah paths wind in four bands around the globe. These ranges are : the prevailing westerly winds and wind north eastern Arctic and the southern hemisphere. Show currents of wind in the upper part of the lower layer of the atmosphere, at an altitude of 10-15 km above the earth's surface. This is called wind currents, jet , where more than wind speed in the center of the jet stream about 320 km / h. Wind systems are called rotary cyclones and anti- cyclones. The winds of hurricanes spin to the inside toward the center of low pressure, while the spin wind in anti- cyclones to the outside around the center of the high pressure.

Air resistance
Resists air movement of objects that move through it. This resistance arises from the movement of objects and friction with atoms and molecules of gases consisting of air. By piece of paper in the air landing slowly toward the ground because of air resistance to it, as to reduce the speed of air resistance parachute jumpers. In the early days of aviation use, the speed of the aircraft was relatively low due to the collision of air Bmrabot wings and rubber wheel of the plane. Aviation engineers stood by reducing the air resistance by making the shape of these parts more streamlined. And canceled the pillars of the wings and landing gear hidden in the fuselage. They also found that the smooth introduction of the aircraft reduce air resistance. The higher the speed of objects in the air has increased air resistance. For example, the more air resistance you and you cyclist the more your speed. Air resistance and generate heat, meteoroid particles moving in the air at high speed which increases air resistance so it becomes very hot. For this reason, most of the meteoritic particles glow and shine , and then burn up before they hit the surface of the earth. Duration spacecraft made ​​of materials withstand the intense heat generated by air resistance.

Compression of the air
Can air pressure inside the cylinder or steel tanks until the pressure reaches hundreds of times the normal atmospheric pressure. The so-called air in this case compressed air. When exposed to the air pressure, the speed of its atoms and molecules become higher , and because of this speed , the air becomes hotter. People use compressed air to blow the wheels and air mattresses, and some divers breathe air from the cylinder filled with compressed air installed on their backs , where divers carrying cylinder filled with compressed air volume up 1/200 of its original size. A submarine -like compartments called ballast tanks with water flow. And ascend to the surface of the water due to the water flow which strongly compressed air. It also uses compressed air to the brakes and cans of pesticide workshops dyes, excavators and other aerobic number.

Gases
The nitrogen ratio of 78% of the total volumes of these gases, and oxygen is 21 % of the volume of the atmosphere , while the remaining part of the antenna cover is mostly composed of water vapor and carbon dioxide. Due to increase the intensity of each of the water vapor and carbon dioxide from the intensity of other other gases, we find them in the layers of the atmosphere near the ground, it is known that about 90 % of the water vapor airborne and is found in a layer of the atmosphere reaches a height of 6 kilometers above the surface the sea , and are found in the envelope of air large amounts of solids suspended , and this solid objects atoms minutes of dust and salt and smoke from factories and cars , locomotives and ships , and cause suspended solids pollution not to cover the antenna , but the hydrosphere as well. In spite of the negative aspects of these solids have the benefits of a good, such as the condensation of water vapor around and coming in the form of drops of water or snow or cold. It is noted that much of the rain that affect inland areas in the region of Saudi Arabia preceded by sandstorms.

Atmospheric pollution antenna
Contaminate the atmosphere when there is a foreign material or when the change occurs is important in the ratios of its constituent, and there are these exotic materials suspended in the air in a solid , liquid or gaseous , and is the factories and combustion products and motor vehicles the most important sources of air pollution at the moment. As well as nuclear testing, pesticides , scientists have counted more than a hundred pollutants to the atmosphere and have devastating effects on the environment and on the dynamic equilibrium. The pollution has become a threat to the ozone layer that protects the earth from harmful radiation hazards. The control of the spread of the pollution of the most important causes of combat, especially the remnants of factories and cars , is to maintain the vegetation of the leading factors purification of air pollution.

The importance of the atmosphere
Provides living creatures with air to breathe. Allows entry into force of visible rays and infrared rays and other thermal and photovoltaic coming from the sun and absorbed by the Earth, which provides warmth and protection. Protects Earth's surface from harmful ultraviolet radiation and prevents the arrival of the Earth that cause many diseases such as skin cancer and skin diseases and many visual Contributes to the organization and distribution of temperatures prevailing on the Earth's surface where the regulated access sunlight and prevents the entry into force of all terrestrial radiation to outer space, if there is no air envelope of the land to bypass the long daily 200 degree heat. The distribution of water vapor at different regions of the world. Protection of organisms on Earth's surface from harmful cosmic radiation, especially ultraviolet radiation. Is a protective shield that protects Earth's surface from meteorites and comets where mostly crumbles before reaching the Earth's surface, as a result of inadvertent contact with air and burned. The connection mode used by aircraft, and transmitted it sounds and not the presence of air in the atmosphere of stillness and tranquility prevailed scary on the surface of the earth. Regulates the proliferation of light properly.

Atmospheric composition
Scientists divide the atmosphere into four layers based on temperature difference. These classes are arranged from lowest to highest are:

1 - tropospheric

2 - stratospheric ( upper layer air )

3 - mesosphere ( Cover East )

4 - Iiyrmosver ( thermal envelope ).

At least the thickness of the atmosphere whenever we rise above the ground. And fade the outer layer of the atmosphere gradually in outer space where he met the solar wind. The solar wind, a constant stream of charged particles from the sun.

Tropospheric

An atmospheric layer adjacent to the surface of the earth, a class in which we live. This class includes 75 % of the total atmosphere. Most of the changes and weather, rain and snow in this class almost. Scientists predict the weather for their studies troposphere. This class also includes most of the water vapor and atmospheric air in the atmosphere. And gives the jet stream in the upper part of this layer. Decreasing temperature in the troposphere is about 6,5 ° m whenever we rise to the top in 1000. Depending decreasing temperature at the beginning of the tropopause ( lower interval ), which represents the upper part of the troposphere. It is located on the end tropopause height 10 kilometers above the Arctic and Antarctic, and at an altitude of 15 km above the equator almost. At the end tropopause air becomes very thin so that is not enough for life. Usually the atmosphere near the Earth's surface warmer because sunlight passing through the atmosphere heats the earth and water vapor. In turn, the Earth heats the air in contact her directly. In some cases, especially during the night during the winter , the air is in contact with the surface colder than the air above it. Here, the temperature increases in a thin layer of the troposphere as we rise to the top. This situation is called a coup anomalous warming. Show the worst air pollution during the occurrence of this phenomenon, because the cold air near the surface of the earth holding pollutants and prevents them from spreading or climb to the top. The last case of the coup warming even eliminate rain or wind on this layer aerobic warm. The air is cool in the tropopause, where clouds composed of ice crystals. The coldest part of the troposphere is Alterboboz located above the equator, where the escalation of the air has a higher-end , air temperature would drop to below the -80 ° m. The temperature of the tropopause over the poles, they increase it above the equator to 30 ° C.

Stratospheric Extending from the tropopause to 50 km above the Earth's surface almost. The amount of moisture that reach this layer of the atmosphere are very few, so the clouds are rare , too. Preferably pilots airlines flying through this layer in order to avoid the vagaries of the weather they encounter in the troposphere. The stratosphere is characterized by temperature almost steadily, but the temperature of the top layer of which increases with increasing altitude, where temperatures in the lower -55 ° C while temperatures in the upper part of them to -2 ° m only , and this part of the stratosphere called Alastratopoz ( class interval ). This section contains the most ozone gas in the atmosphere, as it works on ozone air heating because there absorbed ultraviolet radiation.

Cover East ( the mesosphere ) Extending from the end Alastratopoz to 80 km above the earth's surface. And decreasing the temperature in this layer with altitude where temperatures in the upper parts of them to the lowest possible level in the atmosphere surrounding the Earth. This is the upper part, of the mesosphere is called Almizoboz ( end cover East ). And landing temperature in this part over the poles to below -109 ° m during the summer. And you can see the tail of hot gases flow in this layer by meteors. As can be seen in the very winds of violence within the mesosphere. These winds blowing from west to east in winter. And from east to west in the summer.

Thermal envelope ( layer Iiyrmosver )

Which is the highest layer in the atmosphere. The start of the end of the end Almizoboz and continue to outer space. It features air in this layer that is very light, since 99.99 % of the atmosphere is located below it. The different chemical composition of the air in this class for the rest of the chemical composition of the constituent layers of the atmosphere. In parts of the lower layer Iiyrmosver, shatter most of the oxygen molecules into oxygen atoms. The upper portions of which contains mainly hydrogen and helium. Iiyrmosver layer facing the sun directly, is working to heat the air to light a very high degree. The temperature jump quickly from Almizoboz to 600 ° C at altitude of 200 km above the earth's surface. But in the course of the solar wind up an additional quantity of radiation and particles to Iiyrmosver layer. See the sun. Here, the air becomes hotter, where the degree of Aharah up to more than 2000 ° m at an altitude of 400 km above the earth's surface. And when they hit the sunlight and other sources of radiation coming from cosmic another layer Iiyrmosver, some of the molecules and atoms shipped any electrically ionized. These are called atoms electrically charged ions. There are most of these ions in the lower parts of the Altheromusavyr, so called these parts of the ionosphere layer ( the ionosphere ). Where lead this layer a major role in the long-range radio communications. The class this Unlike electromagnetic waves into the ground instead of spread in space. The daily show in the layer Iiyrmosver cases D Ghazi enormous, and change the tide of these cases direction every six hours. It also shows the natural light in this layer is called Daybreak. The splitting occurs when the Earth attract these ionized atoms in the layer Iiyrmosver it, as shatter the molecules in the layer composed Iiyrmosver ring around the magnetic polarity of Earth, and the resulting energy in the form of light. The so-called Daybreak, which seems in the northern hemisphere Daybreak North. The Daybreak that appears in the southern half of the globe is called Daybreak South. The so-called upper layer Iiyrmosver Alxsosevir ( outer shell ), rising to about 480 km from the Earth's surface to be finished in the solar wind. There is nothing in Aloxosevir little air. Can not find space ships and satellites orbiting the earth in this region little resistance. And moving some of the atoms and molecules in Aloxosevir very rapidly, where overcomes the force of gravity and the earth starts to outer space , and so the earth is gradually losing its atmosphere. But this process needs to be billions of years even come on the overall atmosphere around the globe.

Out of the atmosphere
There is no specific date can be relied upon in forming correct idea about the history of atmospheric composition, that some researchers in the history of the emergence of land reckon it was formed 4.5 billion years ago , and often were not containing atmospheres. Gradually, I began gases emanating from the earth gather around. For example, launched a massive numbers of volcanoes on Earth many emerging gases such as ammonia and carbon dioxide , carbon monoxide , hydrogen, methane , nitrogen, sulfur dioxide and water vapor. Thus formed these gases emitted from volcanoes, the largest part of the atmosphere of the old earth's surface. And condensing a large part of the water vapor emitted from volcanoes to form rivers, lakes and oceans. The rest of the gas constituents of the atmosphere has melted in the ancient oceans or formed crustal rocks. But most of the nitrogen remains in the atmosphere, and added to it later argon and xenon by the decomposition of some radioactive elements on the surface of the earth. It seems that the atmosphere in ancient times did not contain a large proportion of oxygen, but after the emergence of algae and other organisms green plant in the oceans 3.5 billion years ago , began growing, the amount of oxygen as a result of the process of photosynthesis. And the spread of the plants on the Earth's surface is added more oxygen to the atmosphere. And 400 million years ago was the atmosphere often contains the same amount of oxygen contained in the now. As days passed by human activities caused significant changes in atmospheric composition. For example, the addition of carbon dioxide to the atmosphere by burning coal or oil or fuel containing carbon. Since 1900, causing the use of such fuels in an increase in carbon dioxide of 15% of the volume of carbon dioxide in the atmosphere. Overall, the proportion of gases remain in the atmosphere as it is almost over millions of years.

Study air
Since time immemorial, man knew that the air is essential for life. During the fifth century BC, the Greek philosopher Ombaidokulaiz suggested that the four elements air , earth , fire and water combine in different proportions to be a creature. Has assented to the idea of many scientists Greeks. In the fourth century BC, the Greek philosopher Aristotle wrote a book Almitruloggio (ie, meteorology ), which includes the collected observations about the nature of the air and the various forms of weather. Could not philosophers and scientists in the past to test their theories about the air to the lack of devices for measuring the properties of air. Note scientists have begun to air since 1593, when the Italian scientist Galileo invented the barometer of heat. In 1643 invented the Italian scientist Evangelista Torricelli a barometer to measure air pressure. This device has proved that the conditioning and weight. In the middle of the seventeenth century used chemical Irish Robert Boyle barometer to find a formula linking the amount of air and pressure. During the eighteenth century, scientists began studying the constituent gases of air. Oxygen was discovered by Swedish chemist Carl Schell at the beginning of the seventies of the eighteenth century, followed by English chemist Joseph Priestley in 1774. In 1777, he realized the French chemist Antoine Avoizih that oxygen helps the ignition. In 1772, he discovered the Scottish physician Daniel Rutherford nitrogen gas. In 1894, two scientists isolate the two Scottish chemist Sir William Ramsay and the English physicist Baron Riley argon gas. At the end of the nineteenth century scientists found that the installation of the air is similar in all parts of the globe. During the first decade of the twentieth century discovered the Norwegian team headed by physicist Wilhelm Byarknz move air masses. As a result of the confluence of warm air mass cold air mass arises what is called the front, which is different from the weather suddenly. These models have helped to weather systems on the progress in the broad field of accurate prediction of the weather conditions. With the mid-twentieth century got tremendous progress in equipment for the study of the atmosphere. Today, using both radar and missiles, satellites and balloons ( balloons ) to study the weather. These facilities have enabled scientists to monitor the atmosphere continuously, as a measure levels of air pollution and measure changes in the installation of the air. And often carries the balloon SIP device radio ( wireless ), which measures the temperature and air pressure and humidity in the air at various altitudes. Where broadcast transmitters in the SIP device radio weather information to the climatic stations on the Earth's surface. It also helps computers meteorologists to analyze the vast amount of climatic data from various sources and preparation of maps, especially the weather.